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Contents 

9 Dr. DiTolla’s Clinical Tips 

In this issue we take a look at the increased demand 

for BruxZir ® Solid Zirconia crowns. I’ll also introduce 

aveoTSD ® , our newest treatment for problem 

snoring. Also highlighted are Septocaine ® anesthetic 

and Office Art from Discus Dental. 

14 Restorative Photo Essay: 

The IOS FastScan for an 

Anterior BruxZir ® Bridge 

As you’ll see in this issue’s Clinical Tips, BruxZir Solid 

Zirconia was designed as a posterior crown, and 

that is how the vast majority of dentists are using 

it. As we began to get requests for an anterior 

version of BruxZir for patients who had broken 

previous crowns, we decided to give it a try on 

some anterior teeth. Here is a glimpse of my first 

anterior BruxZir case utilizing a digital impression 

scanner we are close to bringing to market. 

28 One-on-One with Dr. Michael DiTolla: 

Interview of Dr. James Dower 

I wanted to check in with Dr. James Dower, professor 

of local anesthesia at my alma mater, University 

of the Pacific, to find out what injections dental students 

are being taught today. Dr. Dower also gives 

his preferred injection technique for repeated success. 

Yep, another Gow-Gates lover. 

44 Rubber Dam Hazards 

Do rubber dams do more harm than good? In another 

iconoclastic article from Dr. Ellis Neiburger, 

the use of rubber dams as an indispensable element 

of quality operative dentistry is examined. 

Dr. Neiburger discusses if advancements in technique 

and material selection have made the need for 

the use of rubber dams, first put into practice in dentistry 

in 1860, largely unnecessary. 

Contents 1

Contents 

50 Photo Essay: Your Questions 

Answered by Dr. Daniel Melker 

For this issue, Dr. Daniel Melker was kind enough 

to compose a list of the most frequently asked questions 

he receives as a specialist. The answers were 

compiled in photo essay format. From contouring after 

biologic shaping to why we barrel in furcations, 

this is a definite must read! 

57 Alginate Substitutes: 

Rationale for Their Use 

Dr. Len Boksman discusses the shortcomings of 

alginate as an impression material and focuses on 

the shift of preferential use of alginate substitute. 

If you don’t already agree, perhaps you will after 

reading his argument for use of alginate substitutes 

thanks to their low-cost, high tear strength and 

stability, among other attributes. 

62 Patient Product Review 

Educating patients can be challenging. After all, my 

drawings can only show so much and sometimes it’s 

hard to explain why I need to build up a tooth just 

to grind it down again. However, thanks to a great 

new patient-education tool by Dental Demo Suite for 

the iPad, engaging your patients and educating them 

into treatment has never been easier. 

2 

chairsidemagazine.com

Publisher 

Jim Glidewell, CDT 

Editor-in-Chief 

Michael DiTolla, DDS, FAGD 

Managing Editors 

Jim Shuck 

Mike Cash, CDT 

Creative Director 

Rachel Pacillas 

Clinical Editor 

Michael DiTolla, DDS, FAGD 

Senior Copy Editor 

Melissa Manna 

Copy Editors 

Kim Watkins, Jennifer Holstein 

Magazine Coordinators 

Lindsey Lauria, Sharon Dowd 

Graphic Designers 

Jamie Austin, Deb Evans, Joel Guerra, 

Phil Nguyen, Gary O’Connell 

Staff Photographers 

Sharon Dowd, Kevin Keithley 

Illustrators 

Wolfgang Friebauer, MDT; Phil Nguyen 

Ad Representative 

Lindsey Lauria 

(lindsey.lauria@glidewelldental.com) 

If you have questions, comments or complaints regarding 

this issue, we want to hear from you. Please e-mail us at 

chairside@glidewelldental.com. Your comments may be 

featured in an upcoming issue or on our website: 

chairsidemagazine.com. 

© 2010 Glidewell Laboratories 

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(“publisher”), Chairside makes Magazine any nor warranty, any employees express or involved implied, in or its assumes publica- 

Neither 

tion any liability (“publisher”), or responsibility makes any for warranty, the accuracy, express completeness, or implied, or or assumes usefulness 

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or 

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ness represents of any that information, its use would apparatus, not infringe product, proprietary or process rights. disclosed, Reference or 

represents herein to any that specific its use would commercial not infringe products, proprietary process, rights. or services Reference by 

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favoring 

by 

trade 

ily by constitute the publisher. or imply The its views endorsement, and opinions recommendation, of authors or expressed favoring 

by herein the do publisher. not necessarily The views state and or reflect opinions those of of authors the publisher expressed and 

herein shall not do be not used necessarily for advertising state or or reflect product those endorsement of the publisher purposes. and 

shall CAUTION: not be When used viewing for advertising the techniques, or product procedures, endorsement theories purposes. and materials 

that When are presented, viewing the you techniques, must make procedures, your own theories decisions and about ma- 

CAUTION: 

terials specific that treatment are presented, for patients you and must exercise make personal your own professional decisions about judgment 

regarding treatment the for need patients for further and exercise clinical personal testing professional or education judg- 

and 

specific 

ment your own regarding clinical the expertise need before further trying clinical to implement testing or new education procedures. and 

your own clinical expertise before trying to implement new procedures. 

Chairside is a registered trademark of Glidewell Laboratories. 

Chairside ® Magazine is a registered trademark of Glidewell Laboratories. 

Editor’s Letter 

It’s an interesting time here at the lab because we have a 

couple of products that doctors are prescribing in record 

numbers. That doesn’t always happen. In fact, there have 

been plenty of products we’ve released to the sound of 

crickets. As a lab that works with a large number of dentists 

in all 50 states, we can get a pretty good idea of what 

is going to be a popular product. 

However, products can’t be forced on dentists; they simply 

won’t buy. Every new product must pass the age-old 

Dr. Gordon Christensen test. That is, is the product faster, 

easier, higher quality and cheaper? In order for your product 

to be successful, it needs to exemplify three to four 

of these characteristics. The magic is in determining what 

faster, easier, higher quality and cheaper means to most 

dentists. 

Take our Silent Nite ® anti-snoring/sleep apnea device, for 

example. It works well and is comfortable, but in the beginning 

adjustment can be slightly confusing for the dentist. 

We have sold tens of thousands of Silent Nite devices, 

but most of them have been single sales to dentists, most 

likely for their own use. 

Three months ago we were introduced to aveoTSD ® , a 

simple anti-snoring device that attaches to the tongue via 

suction. It’s easy to use and there are no impressions or 

adjustments necessary. Because it can be given to the patient 

the same day he or she agrees to treatment, we now 

have dentists calling to order 10 at a time! The runaway 

success of aveoTSD is because of its ability to meet dentists’ 

desire for a product that is faster, easier, higher quality 

and cheaper. 

In this issue, you will also get a peek at the IOS FastScan , 

our answer to digital impressions. While not quite ready 

to be released, our guiding principles in developing this 

technology have been faster, easier, higher quality and 

cheaper. In fact, by using this technology you will be able 

to create some significant savings on your lab bill! Crowns 

sent digitally will cost 20 percent less than crowns sent 

with conventional impressions due to material, shipping 

and labor savings. We will keep you in the loop as to 

when this technology becomes commercially available. 

Yours in quality dentistry, 

Dr. Michael DiTolla 

Editor-in-Chief, Clinical Editor 

mditolla@glidewelldental.com 

Editor’s Letter 3

Letters to the Editor 

“Dear Dr. DiTolla, 

After watching your clinical veneer videos, 

I just prepped a 10-unit case and tomorrow 

I have 6 units. (When it rains, it pours!) 

In the past I have used 3M ESPE RelyX 

veneer cement. Will you please share your 

luting material of choice and technique 

specifics? Your clinical video advocated 

Parkell Brush&Bond and Nexus ® by Kerr, 

which is now NX3 with Optibond. Do you 

use another product? Please let me know. 

I need to get the product ASAP since I will 

place these cases next week.” 

- Sylvia Rogers, DMD, New York, N.Y. 

Dear Sylvia, 

Good for you! Certainly, the more 

you do something, the more proficient 

you become. 

There is no difference between veneer 

cements, only personal preference 

of consistency. I prefer thick 

veneer cement, which is the main 

reason I switched to NX3. Every 

brand of luting cement has a translucent 

shade, which is the shade I use 

most often. I now use Optibond with 

NX3, as you pointed out, because I 

have heard from clinicians like Gordon 

Christensen and Michael Miller 

that the highest bond strengths are 

4 

chairsidemagazine.com 

typically achieved using bonding 

agents and cements from the same 

family. 

After rinsing the water-soluble tryin 

cement from the veneers etched 

with hydrofluoric acid in the lab, we 

place liquid silane in the veneers for 

60 seconds and then air-dry. Next, 

we paint a thin layer of Optibond inside 

the veneers and air thin it before 

placing the veneers under a lid that 

protects them from the light. 

Intraorally, I pumice, rinse and etch 

with phosphoric acid — for 15 seconds 

on enamel, 10 seconds on dentin. 

Next, I paint a thin layer of bonding 

agent on the tooth surface, then 

air thin. Finally, I cure the bonding 

agent on the tooth after air thinning, 

although many clinicians don’t. I 

have noticed a decrease in post-op 

sensitivity when I cure at this point. 

My assistant loads the veneer with 

cement, and I place it on the tooth. 

Using two orangewood sticks, one 

pushing incisally and the other facially, 

I seat the veneer. My assistant 

cures the gingival margin for approximately 

two seconds, and I clean off 

the semi-hard excess with an explorer. 

She then cures for another one to 

two seconds at the gingival. I then 

clean the excess on the lingual and 

interproximal before final curing. 

As you mentioned, we have a couple 

of different videos showing this. And 

while the products may change, the 

technique stays the same. 

- Mike 


How’s everything? I can’t believe it has 

been a year already since I saw you at the 

Greater Long Island meeting. I did a nice 

case with Glidewell recently: IPS e.max ® 

crowns on #7 & 10 and veneers on #8 & 9. 

I locked on the temps as you recommend 

in your videos. My patient kept the gingival 

area as clean as possible, and when I cut 

off the temps the tissue was pink and 

healthy. After tack curing the veneers first 

and removing the excess cement in the 

gingival area, the tissue started to bleed. I 

luckily had tight margins and no bleeding 

seeped under the veneers, but it still was a 

headache. 

Is there anything you can recommend to 

prevent this, and should it cure, what steps 

do you take to continue cementing the 

case?” 

- David M. Rahr, DDS, Kings Park, N.Y. 

Dear David, 

Anytime I have temp veneers on, I 

now find myself pre-treating the gingiva, 

if you will, before I even touch 

it and test it out. At the very least, 

I hit the tissue with ViscoStat ® Clear 

and some soft scrubbing action with 

the Mini Dento-Infusor tip. If that 

process creates bleeding, I place 

Expasyl in the sulcus and wait a few 

minutes before rinsing and proceeding. 

If Viscostat Clear does not cause 

bleeding, I rinse it off and continue 

with the bonding process. In the 

most extreme cases, I will pack an 

Ultrapak ® 00 cord in the sulcus to 

prevent bleeding and retract the tissue 

approximately 0.5 mm as well. 

The biggest difference: I used to begin 

the bonding process with the 

hope the gingiva wouldn’t bleed and 

then deal with it if it did. Now I test 

the gingiva before etching the teeth 

to control it before committing to the 

bonding process in earnest. 

- Mike 


Let me start with a huge thank you for 

the video presentations, articles and 

many techniques that I have learned from 

watching you practice dentistry. As a

Dear Robert, 

Thanks for the kind words! For 

BruxZir Solid Zirconia, dentists are 

using ADA code D2740 Crown − Porrelatively 

young dentist (graduated in 

2003), my day-to-day crown & bridge 

technique has been shaped and formed 

by your teaching. It is always exciting to 

receive the latest issue of Chairside or a 

DVD with innovative things to learn. 

I have started selectively using BruxZir ® 

on some of my posterior cases. Just today 

I had a male patient come in who had 

ground through the porcelain and metal 

on a PFM crown. I re-prepped him for a 

BruxZir crown. What ADA code are you 

using for these BruxZir restorations? Are 

they considered porcelain/ceramic substrate, 

PFM, all-metal or all-ceramic restorations? 

Recently, I purchased the VITA Easyshade ® 

Compact and it has made my life a little 

easier. However, I noticed from your DVDs 

that you prefer to choose shades from the 

Classic shade guide, not the 3D-Master. Is 

there a reason for this? Is it easier on the 

lab techs? I tend to write both on my Rx. I 

thank you once again and look forward to 

your response.” 

- Robert M. Lieder, DDS, Baltimore, Md. 

celain/Ceramic Substrate. 

Unfortunately, not every product 

is made in a 3D-Master shade, so 

the lab technician converts back to 

a VITA Classic shade if the product 

does not come in a 3D-Master 

shade. I typically show the VITA 

Classic shade because it is the one 

used on 92 percent of the lab slips. 

In reality, I think your solution is the 

best: Give the lab tech both shades. 

If there is a 3D-Master shade available 

they can use that. If not, you 

have provided the correct conversion 

for them. 

- Mike 

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Letters to the Editor 5

Contributors 

Michael C. DiTolla, DDS, FAGD 

Dr. Michael DiTolla is Director of Clinical Education & Research at Glidewell Laboratories in Newport 

Beach, Calif. Here, he performs clinical testing on new products in conjunction with the company’s 

R&D Department. Glidewell dental technicians have the privilege of rotating through Dr. DiTolla’s 

operatory and experiencing his commitment to excellence through his prepping and placement of their 

restorations. He is a CR evaluator and lectures nationwide on both restorative and cosmetic dentistry. 

Dr. DiTolla has several clinical programs available on DVD through Glidewell Laboratories. For more 

information on his articles or to receive a free copy of Dr. DiTolla’s clinical presentations, call 888-303- 

4221 or e-mail mditolla@glidewelldental.com. 

Leendert Boksman, DDS, FADI, FICD 

Dr. Leendert “Len” Boksman graduated from the University of Western Ontario Schulich School of 

Medicine and Dentistry in 1972. After private practice in Burlington, Ontario, Canada, Dr. Boksman 

returned to his alma mater as an associate professor of Operative Dentistry in 1979. He completed his 

B.S. in 1984 and was awarded a Fellowship in the Academy of Dentistry International. In 1987 he 

returned to private practice full time. Dr. Boksman was the first International Editorial Board 

Member of REALITY magazine and consulted for 3M ESPE and Caulk/DENTSPLY for more than 20 years. 

Presently, Dr. Boksman is an adjunct clinical professor at the Schulich School of Medicine and Dentistry 

while maintaining a private practice in London, Ontario. He is also a paid part-time consultant, acting 

as Director of Clinical Affairs to Clinical Research Dental Incorporated and Clinician’s Choice. Contact 

Dr. Boksman at lboksman@clinicalresearchdental.com or 519-641-3066, ext. 292. 

James S. Dower Jr., DDS, MA 

Dr. James Dower is an associate professor in the Department of Restorative Dentistry at University of 

the Pacific Arthur A. Dugoni School of Dentistry. He has been the Director of Local Anesthesia Courses, 

which includes a year-round curriculum with three rotations in local anesthesia, since 1979. Dr. Dower 

has presented local anesthesia courses nationally and has published articles internationally. He has a 

master’s degree in Educational and Counseling Psychology. Contact Dr. Dower at jdower@pacific.edu 

or 415-929-6538. 

6 

chairsidemagazine.com

Daniel J. Melker, DDS 

Dr. Daniel Melker graduated from Boston University School of Dentistry in 1975 with specialty training 

in periodontics. Since then, he has maintained a private practice in periodontics in Clearwater, Fla. 

Presently, Dr. Melker lectures at the University of Florida Periodontic and Prosthodontic graduate programs 

on the periodontic-restorative relationship and presents at UAB, UH, Baylor University and LSU. 

He has published several articles in national dental magazines as well as The International Journal of 

Periodontics & Restorative Dentistry. He has twice been honored with the Florida Academy of Cosmetic 

Dentistry Gold Medal. Contact Dr. Melker at 727-725-0100. 

Ellis J. Neiburger, DDS 

Dr. Ellis “Skip” Neiburger graduated from the University of Illinois College of Dentistry in 1968. After 

postgraduate research in Oral Pathology and Forensic Dentistry at the U.S. Armed Forces Institute of 

Pathology, Dr. Neiburger pursued a career as a paleopathologist. He was curator of anthropology at 

the Lake County Museum for 17 years. Dr. Neiburger’s research on ancient anatomy and occlusion has 

taken him throughout the world, and his studies in the areas of prehistoric pathology, dental computing 

and clinical dentistry have been widely published. He is editor and vice president of the American 

Association of Forensic Dentists and has written five books on dentistry. Dr. Neiburger is a general practitioner 

in Waukegan, Ill., and can be contacted at 847-244-0292 or drneiburger.com. 

Gregg Tousignant, CDT 

Gregg graduated from George Brown College with a dental technology degree in 1992. Two years later, 

he passed the U.S. National Board for Certification exam and earned CDT designation. A Certified 

Dental Technician for 12 years, Gregg boasts many achievements, including designation as a certified 

instructor for Heraeus Kulzer, where he provided a number of hands-on programs for indirect 

composites and denture injection systems. He is a sought-after lecturer. Currently, Gregg serves as 

Technical Support Manager for Clinical Research Dental, where he provides technical support and 

hands-on courses consistent with the company’s philosophy, “Teaching Better Dentistry.” Contact him at 

gtousignant@clinicalresearchdental.com. 

Contributors 7

Dr. DiTolla’s 

CLINICAL TIPS 

PRODUCT........ BruxZir ® Solid Zirconia 

SOURCE........... Glidewell Laboratories 

Newport Beach, Calif. 

800-854-7256 

bruxzir.com 

BruxZir Update: I would be lying if I said I wasn’t a little surprised by the meteoric rise of 

BruxZir crowns. As a dentist who has been burned by the failure of all-ceramic crowns in 

the past, I knew there was a need in the market for a high-strength, tooth-colored crown for 

patients who wouldn’t accept cast gold — I just never knew if that was a Southern California 

phenomenon or not. We talk about BruxZir being “more brawn than beauty” because of 

its strength and because it may not look quite as good as a typical all-ceramic crown. In the 

patient’s eyes, however, it looks much more esthetic than cast gold. 

I thought I’d share with you where dentists are most prescribing BruxZir. As expected, dentists 

are primarily using it on first and second molars. We might have to modify our slogan 

one day though, because the first couple anterior BruxZir cases I have placed look pretty 

darn good. I look forward to sharing those results with you in a future issue. 

# OF CASES 

1,600 

1,400 

1,200 

1,000 

800 

600 

400 

200 

0 

TOOTH LOCATION UPPER 

Single Unit Cases 

1,431 

1,434 

954 

1,022 

441 

506 

296 

288 

16 

16 12 12 15 8 21 

16 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 

TOOTH # 

# OF CASES 

2,500 

2,000 

1,500 

1,000 

500 

0 

1,951 

1,750 

TOOTH LOCATION LOWER 

Single Unit Cases 

361 

374 

55 104 20 6 8 5 9 17 130 

1,789 

1,588 

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 

TOOTH # 

62 

Dr. DiTolla’s Clinical Tips 9


CLINICAL TIPS 

PRODUCT........ Septocaine ® 

SOURCE........... Septodont 

Lancaster, Pa. 

800-872-8305 

septodontusa.com 

I love Septocaine for my Rapid Anesthesia Technique; 

I am convinced that it works better than typical 2 percent 

lidocaine for this technique, which is detailed 

in video at glidewelldental.com. I heard Dr. Gordon 

Christensen endorse this anesthetic years ago and 

talk about how the absorption of the anesthetic was 

so good that it could be used to infiltrate lower anterior 

teeth (including bicuspids) without having to give 

a block. As I began to use Septocaine more, I started 

to hear rumblings about a higher incidence of paresthesia 

when it is used for blocks. Dr. James Dower 

and I discuss this in greater detail on page 28. I have 

chosen to stick with 2 percent lidocaine for my block 

injections, but for my Rapid Anesthesia Technique and 

infiltrations (which make up 90 percent of the injections 

I give), I am a Septocaine guy all the way. 

10 chairsidemagazine.com

PRODUCT........ aveoTSD ® 


CLINICAL TIPS 

SOURCE........... Glidewell Laboratories 

Newport Beach, Calif. 

800-334-1979 

getaveo.com 

Snoring and sleep apnea … two words ignored by 

nearly every dental school in the U.S. In fact, most 

dentists aren’t even aware of their role in the treatment 

of Sleep Disordered Breathing. And while you 

might think it’s safe to assume that the average physician 

would be educated on the treatment of snoring 

and sleep apnea, you are wrong. Unfortunately, for 

the roughly 20 million people in the U.S. who suffer 

from sleep apnea, neither profession has made diagnosis 

and treatment of Sleep Disordered Breathing a top 

priority, even though half of all American adults snore 

regularly! The American Academy of Dental Sleep Medicine 

(aadsm.org) would love to educate you on how to 

recognize Sleep Disordered Breathing and the variety 

of oral treatment devices available. 

Glidewell Laboratories is proud to be the North American 

distributor of the aveoTSD, a tongue-stabilizing 

device from New Zealand that we are having trouble 

keeping in stock. Apparently there are more snoring 

dentists than we expected who are trying to score 

points with their spouses! Unlike most oral devices, the 

aveoTSD doesn’t advance the mandible or even attach 

to the teeth. It is an extra-oral appliance with a small 

suction cup that holds the tongue forward, which was 

the whole point of mandibular advancement anyway. 

Because it doesn’t attach to the teeth there are no impressions 

that have to be made, and the medium size 

fits 95 percent of patients. If you have been searching 

for a less intrusive appliance for yourself, a staff member 

or a patient, give the aveoTSD a try. 

Dr. DiTolla’s Clinical Tips11

14 chairsidemagazine.com 

– ARTICLE by Michael C. DiTolla, DDS, FAGD

Restorative Photo Essay 

The IOS FastScan and 

an Anterior BruxZir® Bridge 

For the photo essay that follows, I wanted to highlight a case that demonstrates some of the techniques I use on 

a daily basis, while showing a few new techniques derived from our most recent clinical R&D efforts. The case 

begins with the Rapid Anesthesia Technique and then utilizes the depth-cut based Reverse Preparation Technique. 

Next, we use a BioTemps ® provisional to create an ovate pontic receptor site. After utilizing the Two-Cord Impression 

Technique, we take a digital impression with the IOS FastScan from IOS Technologies. The anterior bridge is then milled 

without a model using BruxZir ® , a solid zirconia material primarily used for posterior teeth. We have received many requests 

from dentists who have wanted to use BruxZir as an anterior bridge material, so I was looking forward to seeing 

what type of esthetic result we could achieve on this first attempt. 

Restorative Photo Essay: The IOS FastScan and an Anterior BruxZir Bridge15

Figure 1: The Rapid Anesthesia Technique was originally created for 

posterior teeth, specifically lower molars. It came from a desire to be 

able to anesthetize individual mandibular molars without having to give 

a lower block. Lower blocks are the injections most likely to be missed 

by dentists; they also have the longest onset. The ability to quickly and 

painlessly anesthetize individual lower molars is a huge benefit to the 

general dentist. The first step is to place the PFG Light topical anesthetic 

(Steven’s Pharmacy; Costa Mesa, Calif.) in the sulcus using an Ultradent 

syringe with a metal Dento-Infusor tip. The PFG Light is left in the sulcus 

for 30 to 40 seconds, then rinsed off. 

Figure 2: The 30-gauge extra short tip is connected to the STA System 

(Milestone Scientific; Livingston, N.J.), and a carpule of Septocaine ® 

(Septodont; Lancaster, Pa.) with 1:200:000 epi is placed in the sulcus 

using the tip of the needle without penetrating the attachment. I step on 

the foot pedal and give two to three drops of anesthetic in the sulcus, 

allowing it to soak for 5 to 10 seconds. At this point, I step on the foot 

pedal again to start the flow of anesthetic, and I advance the needle tip 

through the attachment until I contact bone. Next, I give one-half to twothirds 

of the carpule while the machine confirms that I am in the PDL 

with visual and audio prompts. 

Figure 3: To remove the Maryland bridge, I cut through the connectors 

with a Razor Carbide bur from Axis Dental (Coppell, Texas). Cutting 

through this all-composite bridge is easy for the Razor, and I routinely 

use it to cut through PFMs. In the past, I would cut through porcelain 

with a diamond and then switch to a carbide to cut through the metal 

coping. However, the cutting flutes of the Razor allow it to smoothly cut 

through porcelain and metal, simplifying the procedure. 

Figure 4: To prevent aspiration of the pontic, I cut through one interproximal 

contact and then grab the pontic with forceps and snap it off. A 

dentist once told me the story of a patient aspirating a Maryland bridge 

pontic, and he cut through the second contact and the pontic flew free. 


Figure 5: As often happens, the tissue underneath the pontic was 

chronically irritated and bleeding from being hit with water spray. Patients 

can tell you they use a floss threader nightly, but the truth is always 

revealed when the pontic is removed. Viscostat ® (Ultradent Products; 

South Jordan, Utah) is used to keep things clean and dry. 

Figure 6: A plain Ultrapak ® 00 cord (Ultradent Products) is “flossed” by 

hand on the mesial and distal, leaving a small amount of cord on the 

facial. I use a straight, non-serrated cord packer to place the cord in the 

sulcus on the facial. The two ends of the cord are cut on the lingual so 

they will sit flush in the sulcus. 

Figure 7: Once the 00 cord is packed, it should disappear into the base 

of the sulcus. We then move on to the next step of the Reverse Preparation 

Technique. The 801-021 round bur is used to half its depth to ensure 

adequate gingival reduction, and we cut the initial margin at the same 

time. This technique leads to simple, beautiful and consistent margins. 

Figure 8: The next step of the Reverse Preparation Technique is the 

incisal edge depth cut. Because we are going to restore these teeth to 

the length they are now, we need to reduce 2 mm in order to give our 

technicians room to create a natural incisal edge. This 2 mm depth cutter 

is self-limiting to ensure you don’t overprepare. 


Figure 9: You can clearly see the 2 mm incisal edge depth cut on tooth 

#8. I use the 1.5 mm depth cutter on tooth #10 at the junction of the 

incisal third and middle third. This junction tends to be an area dentists 

chronically under-reduce, which leads to facially prominent crowns that 

are too thin to be esthetically pleasing. 

Figure 10: At this stage you can see all of the depth cuts on tooth #8: 

the 2 mm incisal edge depth cut, the 1.5 mm depth cut and the incisal/ 

middle third junction, and the gingival reduction/deep chamfer from the 

801-021 round bur. Now the prep becomes a race; we know how much 

we have to reduce, so it’s a matter of removing tooth structure in a 

timely fashion. 

Figure 11: The 856-025 bur is my workhorse bur. I love super-coarse 

diamonds in large diameters — what a great way to shape a tooth. 

Small-diameter burs have a tendency to sink into the tooth (especially 

build-up material) because they don’t have the surface area to support 

their own weight. I use the 856-025 for the incisal and facial reductions, 

and interproximal areas where it fits, and the 856-018 for tight interproximal 

areas. 

Figure 12: The 379-023 football bur is used to reduce the lingual surface. 

Because the football bur is convex, we use it to develop a desirable 

concave reduction on the lingual. Typically, we don’t place depth cuts 

on the lingual of anterior teeth because we use the mandibular anterior 

teeth as a guide of how much we have reduced and how much clearance 

we need. 


The IOS FastScan is the only system in which 

you hold the wand still while the camera 

moves within the wand. It is counterbalanced 

so that as the camera moves across its 

40 mm path, you are not able to feel it 

moving. This single capture is equal to four 

or five still frames taken with another system. 

Figure 13: My favorite part of the Reverse Preparation Technique and 

the best thing about electric handpieces is the ability to turn down 

the rpm to 5,000 and turn off the water. My KaVo ELECTROtorque 

(Charlotte, N.C.) has all its torque at 5,000 rpm but spins slowly enough 

that I can turn off the water without overheating the tooth. For once, I 

can see enough to smooth the margin well. 

Figure 14: At this point I know the preps are finished because the depth 

cuts are gone. Before I developed this technique, I used to prep teeth 

and guess when they were done. I always request a prep guide with my 

BioTemps to see if I missed a spot, although this is highly unlikely with 

depth cuts. Now I know the BioTemps will seat completely. 


Figure 15: I can see that the BioTemps will go down all the way once I 

remove the soft tissue interference in the area of the pontic. I told the lab 

I would develop an ovate pontic receptor site, and that I wanted them 

to socket the model 4 mm from the gingival margin of the old Maryland 

bridge pontic. 

Figure 16: Because I hadn’t given an infiltration to prepare the two 

teeth, I needed to anesthetize the soft tissue in the pontic area. Again, 

the STA System was used with Septocaine to provide the anesthesia. 

Because we are in tissue that is tightly bound to the periosteum, I am 

using the STA speed, the slowest on the unit. 

Figure 17: I have done plenty of ovate pontic receptor sites with a hard 

tissue laser, but I was in an old-school mood. I used the 801-021 round 

bur and removed 2 mm of tissue and 1 mm of bone. Biologic width is 

only 2 mm in a pontic area because we do not have to have the 1 mm 

sulcus depth that we typically have around a tooth. 

Figure 18: Now the BioTemps bridge seats completely. I have removed 

the soft tissue interference and created a situation for the new pontic in 

which it appears to be growing directly from the tissue. The BioTemps 

provisional has helped me remove adequate tissue and will help shape 

the tissue during the healing process. 


Figure 19: With the ovate pontic receptor site complete, it is time to 

prepare for the final impression. This begins with the placement of the 

second, or top, cord. This cord is a 2E Ultrapak cord from Ultradent. The 

top cord provides retraction for the impression material, or in this case, 

for the digital impression. 

Figure 20: Oftentimes, once the top cord is placed you are able to see 

some irregularities on the margins you couldn’t see when the marginal 

gingiva was adjacent to the preparation margin. Again, I turn down the 

handpiece to 5,000 rpm, turn off the water and smooth the margin one 

more time so there is no doubt as to the finish line. 

Figure 21: Two Roeko Anatomic Comprecaps (Coltene/Whaledent; 

Cuyahoga Falls, Ohio) are placed and the patient is instructed to bite 

down for 8 to 10 minutes. The new Comprecaps have interproximal cutouts 

to avoid blunting the papilla, especially in a case where a pontic is 

present. Without the support of the pontic in place, it is easy to damage 

the papilla if you aren’t careful. 

Figure 22: After 8 to 10 minutes, the Comprecaps are removed from the 

sulcus, as is the 2E (top) cord. The 00 (bottom) cord remains in place 

during the entire impression procedure and often until the provisional 

has been cemented. A light coat of IOS spray is applied to the preps, 

the pontic area and the adjacent teeth. 


The BruxZir bridge is solid zirconia and has 

no porcelain on the facial. It might not be the 

most beautiful anterior bridge in the world, 

but it just might be the strongest. 

Figure 23: The IOS FastScan is the only system in which you hold the 

wand still while the camera moves within the wand. It is counterbalanced 

so that as the camera moves across its 40 mm path, you are 

not able to feel it moving. This single capture is equal to four or five still 

frames taken with another system. This first capture is straight down 

from the incisal edge. 

Figure 24: The wand is rotated slightly toward the facial to capture the 

facial view of the prepared teeth. Again, the wand is held still while the 

lens moves inside the camera. It takes the IOS FastScan approximately 

one second to capture the information needed. 


Figure 25: The wand is now rotated to the lingual for the final scan of the 

prepared teeth. The computer will then stitch these three views together 

(incisal, facial and lingual) to complete the digital model. As long as you 

treat the tissue well and don’t have any bleeding, this is a stress-free 

procedure. 

Figure 26: If desired, you can capture two interproximal shots to give 

the computer a better idea about the contours of the adjacent teeth. 

Rotate the camera 45 degrees from its normal anterior orientation to 

capture two images of the proximal surfaces of the adjacent teeth. 

Figure 27: My assistant and I will typically use lip retractors in the posterior, 

but in the anterior, finger retraction is often enough. We powder 

the lower anterior teeth in order to scan the bite to create the virtual 

digital model. The upper teeth do not need to be re-powdered if they 

have been kept dry. 

Figure 28: With the patient biting into maximum intercuspation and with 

the teeth powdered, the scanner is held parallel to the facial surfaces of 

the teeth for scanning. The computer can now take the upper and lower 

digital impressions and articulate them properly. 


Figure 29: Now that I am finished scanning the prepped arch and the 

bite relationship, my assistant scans the opposing arch. More often than 

not, she will have done this before I ever walk into the room. In California, 

RDAs with an EF license are authorized to take the final impression, 

whether digitally or conventionally. 

Figure 30: Because this is the opposing arch with no preparations, my 

assistant can capture all the information in two scans: a facioincisal and 

a lingoincisal. Working alone, my assistant uses lip retractors to ensure 

the lips don’t touch the previously powdered teeth. 

Figure 31: We took the shade at the beginning of the appointment but 

neglected to photograph it. If you are using something as simple as 

the VITA Easyshade ® Compact (Vident; Brea, Calif.), avoid the common 

mistake of waiting until the teeth are dehydrated to take the shade; do 

it pre-anesthesia. 

Figure 32: The VITA Easyshade Compact shows a shade of B2 for the 

adjacent tooth (#11). We try to take the shade smack dab in the middle 

third, with as much of the tip in contact with the tooth as possible. You 

can take the shade in the cervical third and the incisal, but only measuring 

the middle third is adequate. 


Figure 33: My assistant likes to place dental floss around bridges with 

ovate pontic sites to ensure excess cement is removed from around the 

bridge. This is especially important when you have prepared an ovate 

pontic receptor site, as we have done here. Cement that stays in the site 

of the surgery will have an adverse effect on the tissue. 

Figure 34: The BioTemps provisional has been cemented into place and 

all of the excess cement has been removed. My assistant left a small 

open embrasure between tooth #8 and #9 to ensure we don’t blunt the 

papilla. Knowing patients won’t use a floss threader around temps, I like 

to leave the gingival embrasures open and have them swish with Tooth 

and Gums Tonic ® (Dental Herb Company; Boca Raton, Fla.) to keep the 

area clean. 

Figure 35: A look at the opposing model as captured by the IOS Fast- 

Scan scanner. Using the two scans we took, we are able to clearly visualize 

the facial, lingual and incisal characteristics. Dental assistants in 

all states can take this scan because they’re already permitted to take 

opposing alginate impressions, for example. 

Figure 36: Here is the prepped arch as captured by the IOS FastScan 

scanner. In addition to capturing the information of the abutment teeth, 

the scanner was also able to accurately read the internal contours of the 

ovate pontic receptor site. Notice how the incisal half of the preparations 

angle toward the lingual because of the position of the 1.5 mm 

depth cut. 


Figure 37: A look at the bite registration as captured by the IOS Fast- 

Scan. In a sense, bite registration is more straightforward digitally because 

you are able to visually verify it as the patient bites in maximum intercuspation. 

Depending on your bite registration technique, it is difficult 

at times to verify whether the patient is truly in maximum intercuspation. 

Figure 38: Here is a BruxZir ® Solid Zirconia anterior bridge at cement 

clean-up. We use RelyX Luting Cement Plus (3M ESPE , St. Paul, 

Minn.) because of its bond strength to dentin, ease of use and simple 

clean-up. If you’ve ever had to cut off crowns cemented with a resinreinforced 

glass ionomer like RelyX before, you know it’s plenty strong. 

Figure 39: This photo was taken on the day of cementation, with a retracted 

smile. This BruxZir bridge is solid zirconia and has no porcelain 

on the facial; it has just been polished and glazed. It might not be the 

most beautiful anterior bridge in the world, but it just might be the strongest. 

The ovate pontic site turned out decent as well, which is sometimes 

difficult to achieve in a retracted photo. 

Figure 40: Here we see a nonretracted smile on the day of cementation. 

You can probably tell that by taking the shade on tooth #11, we 

ended up matching the bridge to that tooth better than to tooth #7. 

Tooth #8 could have been stained to match #7, but then #8 might not 

have matched #9. Ensuring the centrals match is usually job No. 1 in 

smile design. CM 

Visit glidewelldental.com to watch a 15-minute clinical presentation on using the IOS FastScan Optical Impression System to replace an anterior bridge with BruxZir. 



Interview of Dr. James Dower 

– INTERVIEW of James S. Dower Jr., DDS, MA 

by Michael C. DiTolla, DDS, FAGD 

As the local anesthesia instructor at the University 

of the Pacific School of Dentistry, Dr. James 

Dower watched me panic through my first injection 

in 1987. Judging by the sweat pouring down my 

forehead, you would have thought I was performing 

open heart surgery on a mafia boss, not infiltrating 

over tooth #9 on the student unfortunate enough 

to have a surname that alphabetically follows mine. 

Dr. Dower continues to lecture on local anesthesia at 

University of the Pacific, and I wanted to touch base 

with him to gauge his thoughts on some anesthesia 

issues; to hear what injections are being taught in 

school today; and to see whether 4 percent anesthetics 

really do have higher paresthesia rates. 

Interview of Dr. James Dower29

Dr. Michael DiTolla: Let me start off by saying that ever since 

you taught me local anesthesia when I was a dental student, 

it has been a really important focus in dentistry for me. 

I vividly remember giving my first injection in dental school; 

it was an infiltration over tooth #9, and I remember the sweat 

pouring down my forehead. That first injection is one of the 

more stressful moments in dental school, and we get slightly 

more used to it; but as we continue to practice, the administration 

of local anesthesia has the potential to be one of the 

more stressful things we do. What are your thoughts on that? 

Dr. James Dower: It’s funny you bring that up because 

we just finished our first week of the local anesthesia 

block. We started this method of practicing injections during 

the spring quarter, and as you mentioned it creates 

a lot of stress for the students. Many have never had a 

dental injection in their life, so getting an injection for 

the first time from their lab partners who can’t mix alginate, 

well, it creates stress on both sides. But stress is a 

huge component for practitioners who are having trouble 

in their block injections. Of the courses I teach, that is 

probably the group of dentists with the most emotion 

because many of them have such difficulties they are 

actually thinking of getting out of practice, as hard as that 

is to believe. 

MD: Wow, yeah, it’s never been quite to that extreme for me. 

About three years ago I purchased the STA System (Milestone 

Scientific; Livingston, NJ), and I purchased it because I love 

the idea of single-tooth anesthesia on lower molars for crown 

preparation, for example. I loved the idea of not having to potentially 

miss a lower block, especially because patients don’t 

like lower blocks. I didn’t want to give a lower block to do a 

single crown on a lower molar, and I’ve had really good luck 

giving injections with the STA System. But the funny thing is, 

the biggest difference the STA System has made in my life has 

been for the esthetic cases where we’re giving multiple maxillary 

infiltrations. The ability to set this device on its lowest 

speed and to give injections with the carpule being changed 

at the device itself removes so much stress from my life. More 

than 20 years into practice, I realized how stressful it was for 

me to give maxillary infiltrations, for example, in that sensitive 

area under the nose. But with the STA System, a computer 

controls the device at a very slow speed, so I can give 

nearly painless injections. I didn’t realize how stressed I was 

until I got the STA System and all of my anxiety disappeared. 

JD: The knowledge of doing the PDL injection to give 

anesthesia is really a good thing for a person to have. Had 

I not learned the PDL injection and the mylohyoid injection 

early in practice, I would’ve had a real tough time 

because I can’t work on a patient who is in pain. 

The term I really like for PDL, which I read in a study 

from Israel, is the trans-ligamentary injection. It describes 

the process of the needle in the periodontal ligament 


from the solutions going to that cribriform plate of the tooth socket intraosseously. So it’s really an 

indirect intraosseous injection. It’s great to have that for intraosseous anesthesia. Recently, I read 

Dr. William Forbes’ article in Chairside magazine (Vol. 5, Issue 1) discussing alternatives to lower 

blocks. I really liked how he discussed that, as well as other tips on anesthesia. 

I really enjoy the idea of the PDL injection, of being able to limit the area anesthetized. And for 

practitioners, they are able to do things quickly; that can be really great. Of course, in dental school 

we don’t do things quickly, so that will help us with difficult areas. 

MD: That’s a good point — a PDL injection on a lower molar in private practice makes a lot of sense 

because I can set the syringe down and pick up a handpiece right away. I can finish prepping in eight 

minutes, take an impression and have that done in 10 minutes, and put a temporary on. But in dental 

school, with 45 minutes of pulpal anesthesia, it takes that long sometimes to get the instructor to come 

over and check that you broke the contacts correctly on the lower molar. 

JD: That is correct! The length of time it can take does make it such that for clinical purposes, 

treating a tooth as a whole rather than just overcoming some difficulty does make it complicated. I 

really like the point you brought up with the maxillary infiltrations in the incisor regions because 

that is an incredibly sensitive area. You have to give the solution very slowly in order for it to be 

comfortable for the patient. Had someone not gone through the exercise of practicing injections on 

his or her peers, he or she might not understand the importance of giving injections more slowly 

in the incisor region than anywhere else in the mouth. 

MD: Yeah, and what I like about the computer-controlled device is that I don’t have to concentrate on 

giving it as slowly as I can, but instead making sure I don’t give it too fast. I use it on an even lower 

speed than the manufacturer recommends when I’m up there, and I can step on the foot pedal and speed 

up halfway through, once the patient is partially anesthetized. Using the STA System allows me to talk 

to the patient, to make jokes, to talk to my assistant. It lifts my mood, and as a result it lifts the mood of 

the patient. Also, a hidden benefit of this devie is that it really takes away the stress and pain from those 

maxillary infiltrations as well. 

You mentioned the PDL injection and mylohyoid injection, two great techniques to have in your arsenal. 

I’m guessing you’re talking about those in cases where a lower block doesn’t completely anesthetize a 

lower molar. Do you teach these techniques to dental students? Do the students get a chance to try a PDL 

injection and a mylohyoid injection? 

JD: You will be happy to know that we have added three rotations in local anesthesia to the curriculum. 

If I remember correctly, Mike, around the time you were a first-year student, we started in 

the preclinical course giving the inferior alveolar on one day and the Gow-Gates on the other. So, 

the students in the local anesthesia block before entering clinic know how to do those injections. 

During the second rotation, they do PDL injections on each other using both the standard syringe 

and the LIGMAJECT ® (Henke-Sass, Wolf GmbH; Tuttlingen, Germany) syringe because it is so hard 

to give solution with the standard syringe. Students actually do that on each other, and they do it in 

a way that, 40 percent of the time, the person does not feel it at all; 40 percent of the time it feels 

like a probing; and 20 percent of the time it feels like a really sharp probing. Interestingly enough, 

I found this out through one of my students who was a former hygienist. She said, “Hey, I learned a 

technique where it was totally comfortable.” I told her to do it on me, and sure enough, by having the 

needle in the sulcus but not touching the attachment and giving the solution for 10 to 15 seconds, 

then gently touching the attachment and penetrating the solutions for a couple of seconds was relatively 

pain free. Of course, you’ve got to penetrate farther and it feels like you can’t; you go to get 

solution and it feels like you can’t. So this technique that a dental student brought in and taught me 

has made the PDL injection a comfortable injection. From then on, I made PDL injections hands-on, 

with the students practicing on each other. And the students are amazed by how comfortable it is. 

Dental students also learn the mylohyoid injection in the second rotation. So, just into their third 

quarter in the clinic, they have learned both of those injections. I felt they needed to have those 


injections for handling accessory innervation issues. It doesn’t matter how many 

mandibular blocks you give and how thick the root feels; if there are accessory 

nerves coming in, you have to handle those to be effective in anesthesia. 

MD: You know, it’s funny: The PDL technique you just mentioned is pretty much 

how I give it, too. I never really gave it a lot of thought, though, I just knew that I 

put the needle in and that I didn’t want to go into the attachment until I gave a 

couple drops of anesthetic. But I was thinking, well, what am I expecting? Am I 

expecting this to anesthetize the base of the sulcus on contact? It didn’t necessarily 

make a lot of sense to me, but I knew that if I put it in like it was a perio probe, gave 

a couple drops, advanced a little bit into the attachment, gave a couple drops and 

moved along, most patients will say, “I didn’t feel a thing” — especially compared 

to a lower block, where you’ve got to get across a couple muscles to get back where 

you’re going. 

The knowledge of doing 

the PDL injection to 

give anesthesia is really 

a good thing for a person 

to have. Had I not 

learned the PDL injection 

and the mylohyoid 

injection early in practice, 

I would’ve had a 

real tough time because 

I can’t work on a patient 

who is in pain. 

For dental phobics — who I’ve never really enjoyed working on to be honest, but 

you still find them in your practice — the ability to give what’s almost a closedmouth 

injection for a lower molar versus a wide-open lower block will really win 

over some patients. Patients who feared injections suddenly become brave because 

what they really hated was that injection, and it’s so much easier to hide it with a 

pleasant injection without all the soft tissue anesthesia that goes along with a lower 

block. I’ve found it to be a fantastic technique. 

I can tell you that when I was in dental school, we did not learn the Gow-Gates. 

That’s one of the things about local anesthesia I find to be a little intimidating. To 

learn the Gow-Gates in dental school, when you’ve got an instructor standing next 

to you helping you through it, would be ideal. In private practice, it’s pretty easy 

for us to switch from one composite to another, try a different post system or a different 

bur. But when it comes time for somebody who’s been in practice for 10 years 

to try a Gow-Gates on a paying patient without somebody there, that’s a big leap. 

And most of the dentists I talk to say, “Wow, it sounds like it’s a great injection, but 

I’m terrified of telling someone to open wide and then aiming for their ear.” I’m not 

surprised you find it makes a big difference to expose students to a technique like 

Gow-Gates when they’re in dental school. 

JD: It makes a big difference. Of course, having two different techniques to 

use helps if they miss the mandibular block using the standard inferior alveolar 

technique; instead, they can try the Gow-Gates. It’s a real benefit to the 

students, and they love the injection. In fact, at the end of their week in local 

anesthesia I talk to them about it, and about two-thirds of the students prefer 

the Gow-Gates injection to the inferior alveolar. So they’re already planning on 

entering clinic with that as their primary mandibular block. 

It’s good for readers to try something different; it’s an anatomic issue that you 

can’t see that makes it a little more intimidating, but if the practitioner just 

palpates the patient’s neck at the condyle — and of course we’re needing to do 

that in doing temporal mandibular joint exams — if they just palpate that neck 

of the condyle and do their penetration and just aim for that, that’s the Gow- 

Gates. So you know it’s two things they are used to doing: the penetration 

for mandibular block and palpating the temporal mandibular joint area. Just 

those two things together, finding the neck of the condyle and their standard 

technique, and they’ll be fine aiming for it. 

MD: That does break it down into two easy steps. For dentists who didn’t learn the 

Gow-Gates in dental school, it sounds more intimidating than something we’re 

used to doing. I don’t know what we think is going to happen if we try it, but you 


get sort of comfortable doing one thing and it does become difficult to change. So 

if you’re going to work on an average patient who comes in for a crown on tooth 

#18 or #19, are you going to go straight for a Gow-Gates or are you going to do an 

inferior alveolar? What’s your strategy? 

JD: My strategy is the Gow-Gates; it’s my injection of choice. I got lucky because 

I kind of stumbled across the Gow-Gates injection as I was reading to 

keep abreast of everything. Then, my dental assistant had her mother come 

in for the first appointment. And I’m doing the exam, and she’s had so much 

dentistry done — I can still picture the whole thing — on the lower left side, 

and she needs a lot more, and in talking to her she said no one had ever completely 

numbed her lower left side. I cringed thinking she had all this dentistry 

done and hadn’t ever been satisfactorily anesthetized. So, I said to her, “That 

won’t be a problem for me.” Yeah right. So, she comes in for her appointment; 

we start the treatment on the lower left quadrant. I start the mandibular block; 

it’s not successful. I do my second; it’s not successful. Now I’m not looking so 

skilled, so I said, “Well, I just read about this other injection called the Gow- 

Gates.” Because I wasn’t showing my skill, I thought I’d try to act intelligent. 

I did the Gow-Gates and she was ecstatic that she was anesthetized. And that’s 

how I came to know and become a believer in the Gow-Gates. It’s a phenomenal 

mandibular block injection. 

MD: That’s a perfect first Gow-Gates, when you’re starting to sweat working on 

your assistant’s mother and it works! I can see how that would instantly become 

your preferred injection technique, and I’d probably never ditch it because it was 

able to help in that situation. I suppose you don’t give too many traditional lower 

blocks anymore than, do you? 

JD: No, I don’t. The Gow-Gates is my primary injection. One reason is the success 

rate, but another reason is because it can be a higher injection than what’s 

traditionally taught with the Halstead method, but it will take care of some of 

the nerves that will cause accessory innervation. So, it will be high enough up 

there and most often get the mylohyoid and sometimes it will actually get the 

buccal nerve too. And that’s one of the things students think is so cool: With 

one injection at one location, you don’t have to go in and do the buccal injection 

as well, although that isn’t always the case. 

MD: Well, I’ve seen, and correct me here if I’m wrong, but I’ve seen statistics on the 

traditional inferior alveolar that for the first block given, it’s missed 15 to 20 percent 

of the time. What’s your feel for that number? How would you compare that to 

a Gow-Gates being missed on the first attempt? 


JD: You’re a learned man because that’s correct. Fifteen 

to 20 percent of the time the dentist misses the mandibular 

block and needs to give a secondary one. And then, 

well, two things. One, with the Gow-Gates that number 

is far less — I’ll say 90 percent of the time to 95 percent 

of the time, the Gow-Gates gets it with the first injection. 

Another reason, though, that dentists miss the standard 

mandibular block technique is they’re uncertain where 

to penetrate for the injection, because if they don’t see 

that pterygomandibular triangle, all of a sudden they’ve 

lost their visual landmark. And if they use that coronoid 

notch to determine it, well the coronoid notch is really 

too low and the coronoid notch is probably 15 mm lateral 

to where they need to be penetrating, so it can be really 

difficult. That’s one of the reasons the standard inferior 

alveolar is so often used; the dentist doesn’t know what 

to do and there aren’t any landmarks. 

MD: That’s a good point, and I just thought of that the other 

day. A female patient came in, an obese patient in her 50s, 

and when she opened wide there was a lot of fatty tissue back 

there. There wasn’t a landmark to be seen, and I was really 

happy that I was planning on giving her a PDL injection 

on tooth #19. It occurred to me for the first time that, wow, 

this is a great technique on somebody like this, where I know 

I would’ve missed that block the first, second, maybe third 

time because there was so much fatty tissue back there. I just 

couldn’t see the landmarks we traditionally associate with 

a standard lower block. Now on that type of patient, where 

you don’t see the landmark, it’s a little different for the Gow- 

Gates, right? Are you able to use different landmarks in a 

patient like that? 

JD: Well, the landmark in the neck of the condyle will 

help the dentist and the hygienist who is certified in 

local anesthesia know where to aim. But I think the other 

determination, whether it’s the standard injection or the 

Gow-Gates, is that it’s so important to actually feel the 

penetration site. Our first-year students can find the 

penetration site with their eyes closed. Of course the 

hand has to get to the mouth, and they learn by finding 

it on their own. So it’s a tactile type of mandibular 

block, where the person will find where the ramus is running 

up toward the maxilla. Sometimes the absence of 

mandibular molars makes it difficult for a dentist, having 

lost the landmarks they’re used to. But instead the dentist 

can find where the ramus runs up toward the maxilla 

and then find the internal edge and penetrate medial 

to that. If there aren’t landmarks, you can feel that internal 

edge of the ramus, you can run your finger a little farther 

medially and then feel the ligament and go, OK, I’m 

just penetrating between these two structures. So, even 

when the visual landmarks aren’t there, the tactile ones 

always are, and that is really a helpful thing; it’s one of 

the things I really enjoyed in the article by Dr. Forbes. 

He also went over some of the anatomic features for the 


penetration of the mandibular block. 

MD: That’s a great point. I’m just playing with the skull here that sits on my desk as we speak. 

JD: Good! 

MD: I’ve always loved having the skull on my desk because it’s so great for local anesthesia, to be able to 

look and see what’s underneath — what the boney structures are and what’s going to be different. You 

can feel it and look at all the different foramen. I find it to be one of the more fascinating things we do 

as general dentists and certainly one of the areas where constant practice and improved technique will 

pay huge benefits. 

Switching gears here: In the PDL technique I use, I use a 4 percent Septocaine. I’ve used infiltrations, but 

I’ve steered away from using 4 percent anesthetics like the 4 percent Septocaine on blocks because of some 

of the things I’ve seen in the literature. I know you’ve certainly spent some time on this topic, so how do 

you feel about a potentially higher rate of paresthesia with these 4 percent local anesthetics? 

JD: Well, I’m really glad you’ve seen that in the literature; it has sparked your mind and impacted 

your use of the 4 percent solutions. With articaine, I think the thing that the dental practitioner 

needs to look at is the product insert. In the “adverse events” section of the product insert is all 

the information the practitioner needs, including a table of events that happened 1 percent of the 

time or more. Now, they only did 882 treatments with articaine in the FDA study that the product 

insert is from, which reported it having 11 paresthesias. Well, you haven’t had 11 paresthesias in 

your lifetime or the lifetime of pretty much everybody you know, but they have 11 in 882 treatments. 

That’s just radical when they start talking about a 1 percent occurrence in something that is 

life-changing for the dentist, who caused this in a sense to his or her patient, and the patient that 

experiences it. So 11 in 882 just from the product insert: If the dentist were to say to the patient, 

“Well, I can use this local anesthetic, but there’s a 1 in 100 chance you’ll experience paresthesia, 

where numbness is going to continue for two weeks, eight weeks or permanently,” I think the patient 

is going to opt against it. 

The other thing to consider with that product insert is: after the table, it lists by body system the 

other adverse events. And when it comes to the neurologic system, it lists other paresthesias and 

other types of nuero injuries that we really term a paresthesia. So, the study really had 21 paresthesias 

out of 882. I don’t think there needs to be any controversy; I think the product insert speaks 

for itself. 

MD: Wow, that is amazing. I would bet $1 million that if you asked your students to try to get 21 paresthesias 

during their next 882 injections, they couldn’t. As a local anesthesia instructor, do you think you 

could get 21 paresthesias with 2 percent lidocaine if you tried? That seems mind-boggling. 

JD: The truth is, it is a mind-boggling number. So in my directing local anesthesia at the dental 

school since 1978, I don’t know of a single documented paresthesia case. I’ve heard about two or 

three that might have been, but I never saw the patient, never saw a follow-up. When you think 

of the number of chairs we have, 140 in our main clinic being used twice a day, we’re already at 

280 patients per day. So if we don’t get paresthesia doing that many, it’ll just show you there’s no 

way. You know, when you graduated from dental school and when I graduated from dental school, 

paresthesia was a term we knew, but it sounded like something that happened to one in a million. 

So, you’re right, there would be no way to create that with a 2 percent solution. 

MD: Yeah, paresthesia was something that happened to oral surgeons who were taking out wisdom 

teeth in and around the nerve. And then later it happened to dentists who were placing implants in 

and around the nerve. But the true paresthesia that came strictly from an injection was pretty rare. 

So, 21 out of 882 patients is amazing to me; I think most dentists will go their entire career without having 

more than one or two temporary paresthesias. I’m sure there’s the odd person who gets a permanent 

one, but that is really scary. You’re making me happy that I’ve stuck with 2 percent anesthetics for my 


locks. So this would certainly hold true for a Gow-Gates or any other block anesthesia, 

I’m assuming. 

JD: Yes, that’s true. Whichever of the mandibular blocks, that’s where it appears 

to occur. One of the other unfortunate and interesting things that came 

about with the 4 percent solutions is: I had heard the term “paresthesia,” but I 

had never heard the term “dysesthesia.” As you said, we heard about this from 

oral surgeons, and it was from creating physical trauma to the nerve in the 

removal of an impacted tooth. In the sense that we can traumatize a nerve and 

cause it to block conduction with paresthesia, what I read about with the 4 

percent solutions is they have caused dysesthesia. So the other thing is we can 

traumatize a nerve and cause it to continually fire. Patients who experience 

dysesthesia from 4 percent local anesthesia, primarily to the lingual nerve to 

the tongue, describe that it feels like their tongue has just been scalded. But 

that is a chronic phenomenon. I know of patients who have a permanent dysesthesia 

to their tongue, and their life is forever changed. They’re a chronic 

pain patient. So that’s another aspect, not just the paresthesia but also this 

dysesthesia of pain. 

Because I wasn’t showing 

my skill, I thought 

I’d try to act intelligent. I 

did the Gow-Gates and 

she was ecstatic that 

she was anesthetized. 

And that’s how I came 

to know about the Gow- 

Gates and become a believer 

in the Gow-Gates. 

It’s a phenomenal mandibular 

block injection. 

MD: Wow, that is a lot to think about. Even if somebody didn’t fully believe this 

study for whatever reason, it’s in the package insert inside the Septocaine. I have 

to admit I hadn’t taken the time to read that insert. I did see your letter in JADA, 

which is how I became aware of this. But I’m a little ashamed I didn’t read the 

insert before that. You know, we think it’s like lidocaine; it’s got “caine” at the end 

of it. You can see how a dentist might skip that. But the insert contains some pretty 

important information. Let me ask you this: If a patient comes into your office and 

you’re going to be doing multiple maxillary anterior crowns, let’s say they have 

single-unit crowns from tooth #5 all the way over to tooth #12, how are you going 

to approach that in terms of local anesthesia? 

JD: Well, it can be done in a number of ways if the practitioner does not want 

to affect the patient’s use of their lip. If they want to have natural lip use from 

not anesthetizing some of the muscles of facial expression, what we’re doing 

there is infiltrations and then things like what you were mentioning: periodontal 

ligament injection or the injection they call the AMSA by injecting into 

the palate. And really what that injection is doing, it’s really a subperiosteal 

injection, in that the needle is placed at osseous contact. The solution is under 

periosteum, so really it’s another indirect intraosseous injection in the palate. 

We have the PSA nerve in the posterior, and the AMSA is saying there’s an 

anterior superior alveolar and a middle superior alveolar, and that’s the AMSA, 

the anterior and middle. By doing that approach on the palate, a subperiosteal 

injection, we’re saying we’ll anesthetize that anterior middle superior alveolar 

nerve going to those teeth. There was a study done that appeared in JADA, and 

it was really the only study that showed how much solution you would use 

and what areas it would anesthetize and at what frequency. Dr. Al Reader out 

of Ohio State was, I believe, the primary author. Any dentist who wants to do 

that injection into the palate to anesthetize the teeth should read that article to 

get an idea of how successful it’s going to be. What will my frequency of success 

be? Besides the standard approach of infiltrations, that approach of PDL 

injections or doing a subperiosteal on the palate to try to achieve that would 

be some of the other techniques I would use. 

MD: I still do the multiple infiltrations. To me, the patient losing the ability to smile 

is a little bit of a liability, but I want guaranteed profound anesthesia for a while 

if I’m doing that many units. The patient’s comfort is first and foremost in my 

mind. And by the time we get the temporaries on, they’ll probably have a little bit 


of their lip back. So if you’re giving from first bicuspid to first bicuspid over on the 

other side — infiltrations — are you giving a carpule per tooth? Are you splitting 

the difference between a couple of teeth like the central and the lateral? How many 

carpules will you give in a case like that? 

JD: A good way to limit the amount of penetrations is by injection between 

the teeth, as you mentioned. So if it was that first bicuspid to first bicuspid 

situation, if you infiltrated between the cuspid and the first bicuspid, that will 

pick up both of those, and between the lateral and central incisor, you’ll pick 

up both of those. I would say you’ll want to give three-fourths of a carpule. 

If you usually give, let’s say half to three-fourths for a standard infiltration, 

I’d say using three-fourths between the teeth would usually get both teeth. I 

think you’re correct — anesthesia is the most important thing to the patient. 

And with doing the infiltration, you know you’ve got it, where with this AMSA 

technique, you don’t have that assurance until you start working on the teeth 

and find what is anesthetized and what isn’t. 

MD: That’s a good point. I’m trying to think of other injections. I don’t know that 

there’s any other like the Gow-Gates that can be so useful to a GP who’s willing 

to learn it. It doesn’t sound to me like the AMSA is quite the game-changer that 

Gow-Gates could be for a practitioner. Is that correct? 

JD: I would say so, yes. You know I feel the same as you do, Mike. Besides 

wanting the assurance of anesthesia, I know where my pre-gingival margins 

are, so I’ve got that. I know preoperatively where the lip line is if I want to use 

that. So to cosmetically have, after you’ve done your dentistry, the patient’s lip 

be normal, I don’t see that as having much importance as compared to knowing 

that we have anesthesia. 

MD: That’s a good point. I was flipping through a journal the other day and saw 

an ad for an anesthesia-reversal agent. As you know, patients enjoy the effects 

of local anesthesia because it keeps them from experiencing pain, but they don’t 

necessarily enjoy the injections — the path you have to use to get there. This anesthesia-reversal 

agent also has to be injected, and I don’t think I could put myself 

in the mindset of saying to a patient, “OK, well your appointment is done, but I’ve 

got to give you one last shot to un-numb you.” I think the patient would say, “Well, 

won’t it wear off on its own?” I don’t know how quickly it reverses the anesthesia, 

but I like that patients are going to be numb for another hour or so and it’s going 

to gradually taper off. If I did something that is going to cause inflammation, they 

have the chance to take 800 mg of ibuprofen before it fully wears off. I’m not totally 

sold on the idea of giving someone one last injection at the end of the appointment 


to reverse the effects more quickly. Am I missing something 

here? Is this maybe something that has limited applications? 

I could see that it makes a lot of sense for children. 

JD: Once again I really respect your thought line because 

I, too, don’t see much usefulness for this reversal anesthetic. 

It works by dilating the blood vessels that we restricted 

with epinephrine, causing the duration to lessen. 

But like you say, hey, I’m going to give you one more 

shot. And, of course, the expense of the materials, too. 

And, as you say, having that period of time if we cause 

some pulpal inflammation to have the patient in a period 

of anesthesia where they won’t feel anything once the anesthetic 

wears off is important. The other important thing, 

especially for mandibular blocks and the PSA injection is, 

we know when we give an injection we aspirate first to 

make sure we’re not in a blood vessel. If we are, we back 

up a little bit, aspirate again and inject. And, of course, 

we’re using a vasoconstrictor in the local anesthetic so 

it’s going to take care of that little puncture we did. But if 

you did the same thing with the reverse, if you puncture 

the blood vessel and back up and give your solution, now 

you’ve dilated that puncture in the blood vessel. So I have 

a concern as far as hemorrhage effects from using a vasoconstrictor 

with the potential of penetrating a blood vessel. 

I guess one of the places in their study that I felt tried 

to avoid an area of issue was, as I understand it, they did 

not do the PSA injection. Of course, that’s the one where 

dentists worry about a hematoma. Then again, if you were 

worried about a hematoma with a vasoconstrictor, what 

kind of hematoma would you get with a vasodilator? 

MD: It’d be a full-face hematoma! It’s funny; I remember in 

dental school when I received my first PSA from the student 

to my left, who was a hygienist and had already been giving 

injections. I was excited that someone with experience 

was going to be working on me. I remember going downstairs 

after the clinic and somebody saying to me, “What 

happened to your face?” and I was like, “What?” And I 

actually received a hematoma on the very first PSA that I 

ever got, and I had to go through all the phases of colored 

bruises on the side of the face. But the student who gave it 

to me also baked me cookies for about a month after that, 

so it was a good tradeoff! I’ve always been very attune to 

carefully aspirating since I’ve gone through that myself. 

I agree that leaving hematoma out of the study seems 

suspicious at worst or terribly absent-minded at best. 

I was having a discussion with my dad the other day, and I 

think he was being serious with me, but he said when he was 

in dental school, I think from 1961 to 1964, needles were not 

disposable. Is that true? 

JD: It’s hard to imagine, but the needles were not disposable. 

They would try to sharpen them up. It wasn’t too 

much earlier from when you were a dental student that a 


dentist would reuse prophy cups and prophy brushes and saliva injectors. 

MD: Wow. 

JD: Yes, I know. Dentistry has changed. 

MD: I don’t know how many times you can sharpen a needle, or if you just go to give an injection and it 

won’t penetrate the mucosa and you break down and say, “OK, I guess we’re going to have to use a new 

needle now.” 

When I was in dental school, we were taught to give lower blocks with a 27-gauge extra-long needle, and 

all my friends who went to USC are big fans of the 25-gauge needle. And when I look at it, it really scares 

me. I know it’s not that different from a 27-gauge, but it looks like it’s on a whole other level. Do you guys 

still teach the 27-gauge at UOP, and can you describe the difference between those two needles? 

JD: Yeah, we still use the 27-gauge. And yes, the 25-gauge when put up against a 27-gauge looks 

big, it looks wide — although a benefit of a wide needle is that it’s supposed to deflect less. Also, 

you’ll know for certain if you’re in a blood vessel to a higher degree of certainty than with a 27. 

At the same time, when you’ve made that hole in the blood vessel with the 25, it’s a bigger hole. 

And you know, they’ll say the 25 is no more painful than the 27-gauge, but the study they’ll do 

won’t be a true study of the injection. It’ll be similar to when they say topicals don’t work. They’ll 

take a needle and take it to periosteum. It’s like, well, wait a minute now — we don’t use these 

things without topical and without anesthetizing ahead. So although I definitely wouldn’t say the 

25-gauge is improper, I’m a person that likes the 27-gauge and I feel like it’s a great needle. One 

of the things I think also confuses practitioners is: I remember getting out of school and a short 

needle was a short needle, a long needle was a long needle. I remember in the first practice I associated 

in, I was looking at the long needle thinking, “Wow, that thing looks so long.” And I thought, 

well, no, it’s a long needle; it just looks extra long to me. Well, it turned out that our 27-gauge 

needle at school was 32 mm long and this needle was 40 mm long. So I think it’s really important 

for the practitioner to know the length of the needle they’re used to, and if they order something 

different, to check it. Eight millimeters is a big difference. 

MD: Yeah, 8 mm is a big difference, and you would no doubt be able to see it. I’m wondering, I know the 

puncture points are relatively the same, but is the target area for the Gow-Gates a linear measurement? 

Is it farther away than a traditional lower block? 

JD: I would say the answer to that is yes. At UOP, we’re still going 25 mm to 30 mm on inferior 

alveolar and Gow-Gates; at least that’s our primary range. But I think you’re right — that’s really 

intuitive that you’ve come up with that. It is a little farther distance to get to the neck of the condyle, 

than say to get to a mid-ramus depth. But, it’s interesting; we’re doing it still in that 25 mm to 

30 mm range for the most part and having success. But you’re right, looking at it anatomically you’d 

figure, OK, it looks like we should go deeper for the Gow-Gates. 

MD: Yeah, I was just picturing the difference in needle lengths you were mentioning. If a practitioner 

had been using a shorter 27-gauge, and he or she had a needle that was too short, they would come away 

from it saying, “Oh, I tried that Gow-Gates; it doesn’t work.” It would seem like maybe the extra 8 mm 

could be helpful for that type of block when you’re giving it for the first time. 

A lecturer once said he was giving lower blocks with 30-gauges very successfully because he felt the 

30-gauge was even less painful than the 27-gauge needle. And I tried a few of them like that, and I’ve 

never tried a 25-gauge, so I’ll just accept what you say is true, that the 27-gauge deflects more than the 

25, but there’s a huge jump there. When I tried to give a couple lower blocks with a 30-gauge just to see 

what it was like, I could feel the deflection taking place. 

JD: I would agree with you. The 30-gauge has a lot of deflection, and you know we usually use 

it in deflections where we don’t go that deep. So, to take that 25 mm to 30 mm, that can have a 


lot of deflection. Just like you say, it’s almost as though you could feel it when 

you penetrate tissue; you could almost see the needle deflecting and bending 

in the outer tissue. And it is interesting because, similar to you, I know dentists 

who use 30-gauge needles for mandibular blocks, and they’ll even use 30-gauge 

short needles, and it blows my mind, but they say they’re successful. It’s really a 

curious phenomenon that some dentists use all these different diameter needles 

and different length needles and have success, and some practitioners have tried 

everything and can’t get success with anything for a mandibular block. 

Fifteen to 20 percent 

of the time, the dentist 

misses the mandibular 

block and needs to give 

a secondary one. And 

then, well, two things. 

One, with the Gow- 

Gates that number is far 

less — I’ll say 90 percent 

of the time to 95 

percent of the time, the 

Gow-Gates gets it with 

the first injection. 

MD: Yeah, that is. The majority of what I do, and the majority of what a lot of other 

general dentists that I talk to do, is one and two single-unit crowns. You know, you’re 

doing a single-unit crown on a tooth that broke and nothing else in the quadrant 

needs anything. So my favorite needle has become the 30-gauge extra-short with the 

PDL, which I learned today was kind of an intraosseous technique at the same time. 

I had tried intraosseous injections before because I liked the idea of getting so close 

to a tooth and not having to give a block, but I always found it really difficult. I 

remember that Stabadex system where you would pierce the mucosa and make the 

hole in the bone and then hopefully when you went back to put the anesthetic in the 

hole, the soft tissue still lined up with the hole in the bone. And it always felt strange 

to put a hole in the bone just to put some anesthesia in there. It seems some of those 

systems have fallen out of favor, but I like the idea that we can use this other, what we 

would traditionally term a PDL, and get that same kind of effect. 

JD: Yeah, it really works well that way. And with that direct intraosseous system, 

I think one of the things practitioners like about the improved version of the 

X-tip system is the little sleeve to put the needle in to help with placement. So 

that is a helpful technique, but like you said, using a PDL technique to create that 

same situation of anesthetic going intraosseously works well, too. 

MD: I didn’t really follow up with this question when we talked about it, but I’ve heard 

a lot of lecturers say for probably 10 years now that Septocaine is great for infiltrations. 

They say you can actually infiltrate teeth that you couldn’t before: lower bicuspids 

and lower anteriors. If you used it on a maxillary tooth, you could pack cord on 

the palatal without giving additional anesthesia. I’ve largely found this to be true, so 

I’ve liked Septocaine as an infiltration. We spoke specifically of what you don’t like 

about Septocaine as a block anesthetic, but do you like it as an infiltration anesthetic? 

JD: Well, I agree with what you’ve said, for infiltration it is more successful. I 

believe both 4 percents are more successful, but articaine definitely in the infiltration 

injections are where 2 and 3 percents should not be relied on. I would 

probably go to prilocaine myself — it’s a 4 percent. The other thing, there are 

some patients — substance abusers or former substance abusers, and it may be 

20 years since they first got clean — for which our 2 percent local anesthetic 

will just not anesthetize them. Four percent prilocaine is what I’d use for patients 

who aren’t numbed by 2 percent anesthetic, so I really like it for that. 

You mentioned earlier about not using 4 percent for the PDL injection, and I concur. 

There’s a higher degree of postoperative sensitivity using a 4 percent in attached 

gingival, doing an interdental injection, or doing the nasal palatine or doing 

the PDL. I would say, in those places, I don’t care for the 4 percent solution. 

MD: OK, interesting. Well, that was a quick hour; the time just flew by. It was fascinating. 

Do you have any upcoming courses or an easy way for dentists to check on your 

lecture schedule to see where you’re going to be speaking? 

JD: Thank you for asking, Mike, I appreciate that. I stopped speaking outside the 


dental school about 10 years ago, so currently I give the course at the University 

of Pacific Arthur A. Dugoni School of Dentistry a couple times a year. It’s 

a hands-on course, so the dentist will learn the Gow-Gates and many of the 

other things we’ve talked about. I thoroughly enjoy teaching these courses and 

enjoy working with practitioners and helping them, so they’re comfortable 

when they treat their patients. 

MD: Yeah, that’s a great idea. I flew more than 100,000 miles last year lecturing 

and I would like to settle down, too, because the airplanes and the hotels get a little 

old after awhile. That’s easy enough: If they want to take your course, they just 

need to come spend a weekend in San Francisco at the best dental school in the 

country — the University of the Pacific Arthur A. Dugoni School of Dentistry, which 

I’m proud to call my alma mater. 

I appreciate your time today. It’s been fantastic, and you have given our readers 

something to think about. Once again, I’ll issue my challenge to GPs reading this 

article: What’s keeping you from giving a Gow-Gates? It sounds like it can solve 

the issues of incomplete mandibular anesthesia that we’ve all fought during our 

careers. We’ll see if 2010 is the year we get more GPs to try the Gow-Gates. 

Thanks again for your time. I really appreciate it. 

JD: Thanks, Mike. And thanks for what you’re doing with Chairside magazine. 

I think it’s really beneficial to the practitioner. Good talking with you. It was 

fun to pull out my class picture from the class of 1988 and look through some 

of the faces as you were recalling the hematoma. I was looking at the picture 

thinking, OK, I think that person’s initials were R.D., trying to figure out who 

caused your hematoma that benefitted you with many cookies. 

MD: It was actually K.D., Kristi Doverance. You know you seat by alphabetical order, 

and she was on my left. And she’s now an oral surgeon. She was really one of 

the stars of our class. Of course, right next to her was Mike Doy, who had been a lab 

tech for 13 years before going to dental school, so every time we had to wax something 

up he was done in three minutes and after two hours ours still looked like 

crap. But it was really sort of a star-studded row. I had Rob Cunin there, who went 

on to go to orthodontic school. Kristi was fantastic with her hands. It just goes to 

prove you can do everything right and still get a hematoma. The truth of the matter 

is, we’re always trying to get the tip of the needle right back in that area, aren’t we? 

JD: Yes. Interestingly enough, our PSA technique is like our infiltration technique 

in that it’s parallel with our alveolar bone. And, like you said, even 


though you get the best operator using the correct technique, 

bad things happen to good people. 

MD: It wasn’t that bad. If that had been the biggest problem 

of my life, my life would’ve been easy! CM 

Dr. James Dower is an associate professor at the University of the Pacific Arthur 

A. Dugoni School of Dentistry. Contact him at jdower@pacific.edu or 415-929- 

6538. 


Rubber DaM 

Haz rds 

– Article and Clinical Photos 

by Ellis J. Neiburger, DDS 

Though repeatedly proclaimed as an indispensable 

element of quality operative dentistry, the rubber 

dam is seldom used in private practice. This is because 

the numerous hazards and inconveniences for the patient 

and dentist are rarely mentioned. These dangers and 

more effective alternatives to the dam’s use in modern 

dentistry are discussed in this article. 

Since Dr. Sanford Barnum’s popularization in the 1860s, 

the rubber dam has been used in most fields of dentistry. 1 

With the help of ligatures and clamps, the rubber dam is 

considered a benefit to the dentist and the patient. Skill in 

its application is a required feature of most dental schools 

and license examinations. 2,3 Many authors have expressed 

its use as a symbol of high-quality, meticulous dentistry 

and its non-use as an example of shoddy dental treatment 

bordering on malpractice. 1,3 

“Many clinicians and educators 

have insisted that the rubber 

dam should be routinely 

used in quality dentistry and 

medical-legal protection, 

even though good dental 

care (including successful 

malpractice defense) can 

be accomplished without it.” 


The rubber dam has been used for dozens of reasons: to 

provide a clear field; saliva and muscle control; aspiration 

and infection prevention; gingival isolation from caustic 

agents; and treatment time-saver. 1−9 Many clinicians and 

educators have insisted that the rubber dam should be 

routinely used in quality dentistry and medical-legal protection, 

even though good dental care (including successful 

malpractice defense) can be accomplished without 

it. 9−12 Although actively promoted in dental schools and 

literature, very few practitioners routinely use a rubber 

dam. 3,11 

Most dental literature describes the rubber dam in positive 

terms, but little is mentioned about its many hazards 

to the patient and staff or the many superior alternatives 

to its use. Because most literature stresses only the benefits 

of the rubber dam, this article will emphasize the 

dangers related to its use in an effort to encourage a balanced 

perspective. 

Figure 1: Most dams are made from latex and tend to tear. 

In the early days of dentistry, practitioners had few ways 

of controlling the oral environment during restorative 

work. The instruments and materials available to the 

dentist of the 1860s−1930s were used for lengthy procedures 

during which a completely dry and clearly visible 

field was needed. The rubber dam was developed for this 

purpose and numerous techniques were devised for its 

use. These techniques, compromises of classical dam 

technique, included the split dam, mini dam, double dam 

and large hole techniques. 4,13 In earlier times, use of the 

rubber dam was necessary to ensure a quality restoration 

or course of treatment. Today, such necessities are rare. 

Hazards 

The use of the rubber dam presents hazards that can 

be classified into three categories: material limitations, 

improper application and inadequate design situations. 

Figure 2: Damaged gingiva from a rubber dam clamp sliding apically 

Material Limitations of the Rubber Dam 

Most rubber dams are made from latex and tend to tear, 

leak and disintegrate as they quickly age, a process accelerated 

by a few days of exposure to air and its pollutants 

(0 3 

, NO 2 

) (Fig. 1). 4,14 Latex tends to decompose or melt 

near flame and under high-intensity lights (e.g., during 

bleaching). It is difficult to patch in the event of rips, it 

sticks to numerous restorative materials (impression putty, 

adhesives), and it can lose its integrity when exposed 

to certain solvents (e.g., alcohol, methacrylate). 2,19 

Figure 3: Radiograph of a rubber dam clamp and amalgam swallowed 

by a patient 

Rubber Dam Hazards45

The rubber dam is difficult to sterilize because it is easily 

damaged by heat and disinfectant chemicals. (Most dentists 

use dams directly from the nonsterile box.) Contrary 

to popular belief, the latex in the dam poorly insulates 

the staff and patient from infectious microbes such as 

Hepatitis B or HIV. It distorts light through reflection and 

produces abnormal color contrasts. 14,15 It often gives off 

a rubber odor. 

The rubber dam contacts the patient’s face and oral tissues 

(with or without a napkin) and can initiate moderate 

to severe allergic reactions in sensitized patients and 

staff. 16−18 

Figure 4: Gingival laceration and apical migration of the epithelial attachment 

by rubber dam application is shown. 

“The rubber dam still affords 

practical uses in modern 

dentistry and should not 

be abandoned. Unfortunately, 

advocating unrestricted and 

arbitrary widespread use, 

often under the guise of good 

dental practice, is abusive 

to the patient and the dentist 

when more efficient and 

comfortable alternatives exist.” 

Improper Application and Use 

With a limited number of clamp sizes fitting an unlimited 

variety of tooth shapes, rubber dam clamps often gouge 

the gingival and abrade the cementum and root surface, 

especially when inadequately seated and supported 

(Fig. 2). 20 Clamps tend to crack porcelain crowns, break 

at the bow and pose danger of ingestion (Fig. 3). 3 The 

clamps and dam can cause further damage when placed 

on teeth that are poorly shaped, partially erupted, decayed 

(gingivally) and in tight contact with each other. 

Gingiva can be lacerated with resultant periodontal damage 

and bateremia when seating clamps (Fig. 4). 5,19 The 

placement of the dam is time consuming for the dentist 

and prolongs treatment time for the patient, especially 

when dam weight, frame, hole location, sizing and dam 

placement is not precise. A torn dam will compromise 

saliva control and may leave difficult-to-find rubber 

fragments in the gingival sulcus, resulting in soft tissue 

inflammation, apical migration of the epithelial attachment 

and possible tooth loss (Fig. 2, 4). 

Inadequate Design Situation 

Not all patients are ideal candidates for rubber dam application. 

Phobics and other psychologically limited patients 

may be further agitated by wearing the dam and 

by the feelings of helplessness and personal invasion that 

its presence denotes. The dam restricts normal mouth 

movement, which adds stress to the dental procedure. It 

is contraindicated in epileptics, some disabled people and 

patients who may experience aspiration of their vomit, 

psychogenic coughing or gagging. 21 The presence of the 

dam can snag burs and rotary instruments, drawing them 

into the soft tissue (Fig. 5). It can hide serious bleeding 

beneath the dam (e.g., hemophilia, blood thinner), thus 


potentially delaying immediate treatment (Fig. 5). The latex 

can fragment and be driven gingivally or inhaled during 

oral placement and removal. 5,7,21 

The dam can also retard the full visualization of the oral 

cavity (e.g., lingual fold), obstructing the view of nonisolated 

teeth, blocking high-speed suction and irritating 

the patient’s mucosa and skin. 6,17,18 Removal of the dam 

can damage new restorations and increase the danger of 

aspirations. 7,20 

Alternatives 

Dentistry has greatly advanced since the 1860s introduction 

of the rubber dam. Long periods of painful intraoral 

treatment are no longer routine. Materials are easy to apply 

and relatively quick setting. 

Today’s patient is well educated and cooperative when 

compared with their Victorian-age relatives who required 

dam use. Many alternatives to the use of the rubber dam 

are now available. These include high-speed suction, 

custom retraction devices, disposable cotton rolls, gauze 

packs and throat screens, retraction cord systems, electrosurgery 

and relatively moisture-tolerant restorative materials 

(e.g., low zinc amalgam versus gold foils). 5,22 

“Like the tooth key, gold foil 

restoration and the 22 kt gold 

shell crown (which were once 

considered good dentistry), 

the rubber dam should take 

its place as a historical friend 

and occasional adjunct to 

dental treatment. It should 

not be taught nor used as 

a constant (and overutilized) 

companion to 

the modern practitioner.” 

The rubber dam still affords practical uses in modern 

dentistry and should not be abandoned. Unfortunately, 

advocating unrestricted and arbitrary widespread use, 

often under the guise of good dental practice, is abusive 

to the patient and the dentist when more efficient 

and comfortable alternatives exist. This antiquated technology 

consumes too much valuable energy, materials, 

and time of dental school faculty and licensing boards at 

the expense of more significant procedures such as bonding. 

Today, very few dentists (approximately 5 percent) 

routinely use the dam. General application of the rubber 

dam is hazardous to the patient, costly in time, effort and 

money and, with few exceptions, is seldom necessary in 

the contemporary dental practice. 

Like the tooth key, gold foil restoration and the 22 kt gold 

shell crown (which were once considered good dentistry), 

the rubber dam should take its place as a historical friend 

and occasional adjunct to dental treatment. It should not 

be taught or used as a constant (and overutilized) companion 

to the modern practitioner. CM 

Figure 5: A rubber dam can be snagged by contact with a high-speed 

dental handpiece. 

Rubber Dam Hazards47

References 

1. Francis CE. The rubber dam. Dent Cosmos 1865. 7:185−187. 

2. Ireland L. The rubber dam. Texas Dent J 1962. 3:1−10. 

3. Prime JM. Fifty-seven reasons for using the rubber dam. Illinois Dent J 1938. 7:197. 

4. Brownbill J. Double rubber dam. Quintessence Intl 1987. 18:10,699−700. 

5. Barkmeier W. Prevention of swallowing or aspiration of foreign objects. JADA 1978. 97:9:473−475. 

6. Seals M, et al. Pulmonary aspiration of a metal casting. JADA 17:10 1988:587−588. 

7. Fischman SL. Prevention, management and documentation of swallowed dental objects. JADA 111:9 1985:464−5. 

8. Emery C. Rubber dam and cross infection. Br. Dent J 1987 163:7:215. 

9. Forrest WR, et al. AIDS and hepatitis prevention: role of the rubber dam. Oper Dent 1986 11:4:159. 

10. Heling B. Endodontic procedure must never be done without the rubber dam. Oral Surgery 1977. 43:464−6. 

11. Bramwell JD, et al. The rubber dam — an insurance policy against litigation. J Endodontics 1986:12(8):363-367. 

12. Sprow vs Ward, Ala 441 So2d 898, 1983. 

13. Farber J. A large hold rubber dam technique. Quintessence Intl. 1980:7:23−5. 

14. Baker R. Precautions when lightning strikes during monsoon: the effect of ozone on condoms. JAMA 1988:260:10:1404−5. 

15. Reingold A, et al. Failure of gloves and other protective devices to prevent transmission of hepatitis B virus to oral surgeons. JAMA 1988:259:17:2558−60. 

16. Blinkhorn AS, et al. Letter Br. Dent J. 6/9 1984:157:56. 

17. Levy HD. Allergic reactions. Br. Dental J. 7/14 1984:157(1)5. 

18. March PJ. An allergic reaction to latex rubber gloves. JADA 1988 117:10:590−1. 

19. Smigel I. Bonding hints easily tackle some special problem areas. Dentistry Today 2/1988:54. 

20. Alexander RE. Rubber dam clamp ingestion, an operative risk. JADA 1971:82(6):1378. 

21. U.S. Dept. H.E. W. The dental implications of epilepsy 1977:2. 

22. Van Dijken JW, et al. Effect of the use of rubber dam versus cotton rolls. Acta Odontol Scand 1987:45(5):303−8. 

Dr. Ellis Neiburger is a general practitioner in Waukegan, Ill. He is director of the Center for Dental AIDS Research and vice president/editor of the American Association 

of Forensic Dentists. Contact Dr. Neiburger at eneiburger@comcast.net or 847-244-0292. 

Copyright © 2010 Ellis J. Neiburger. All rights reserved. 


Periodontal 

Photo Essay 

– ARTICLE and CLINICAL PHOTOS by 

Daniel J. Melker, DDS 

Tooth #30 exhibits a Class II furcation with the old 

margin approximating the furcation. 

Q: Why do we barrel in furcations? 

A: By removing the overhanging lip 

on the furcation, we usually find bone to be more 

coronal in the furcation, creating a parabolic 

architecture and maintainable environment. 

No further breakdown should occur. 

After biologic shaping, the overhang of the furcation 

is removed to allow for a more maintainable 

furcation area. 

Completed restoration with the contours of the new 

restoration mimicking the shaped root surface 


When the furcation is removed and the new restoration 

places the furcation back in that area, it becomes 

a location for plaque accumulation. 

Q: Why do we barrel in a furcation 

to the occlusal surface when fabri- 

A: 

cating a new crown? 

When we contour the crown so 

the barreling in goes to the occlusal surface, the 

patient can clean everywhere; there is no plaque 

buildup. If we can stop short of the occlusal surface, 

we find plaque accumulates and it is as 

though the furcation is still present. 

After biologic shaping, the furcation is replaced and 

the area accumulates plaque. 

The furcation was removed but replaced in the final 

restoration. The tissue has become inflamed from the 

root being replaced because of plaque accumulation. 

Periodontal Photo Essay51

Q: How do you contour a new 

restoration once the tooth has 

A: 

been biologically shaped? 

The new restoration follows the 

contours of the shaped tooth and does not have 

a height contour placed on the buccal. 

Occlusal view on the day of impression 

Buccal view on the day of impression 

Buccal furcation contours carried to the occlusal 

surface of tooth #30 


Contours of shaped teeth are shown. 

An occlusal view of shaped teeth and, in particular, 

barreled in furcation of teeth #30 & 31. 

Restorations mimic shaped teeth. 

Q: Should the contours of the new 

restoration follow the shaped tooth? 

A: Yes, to allow for the proper maintenance 

by the patient and hygienist. As previously 

discussed, any furcation that is barreled in should 

be carried to the occlusal surface. 

Restorations placed on teeth mimic shaped teeth. 

Periodontal Photo Essay53

Tooth #30 appears to have minimal periodontal issues, 

based on tissue appearance. 

Vertical probing is minimal (2 mm) in the furcation 

area. 

Upon reflection of the flap, the existing margin 

ends in the furcation. A significant problem exists 

in terms of the furcation breaking down further over 

time if left that close to the final margin. 

Q: Does vertical probing in 

the furcation area tell what 

A: 

periodontal issues may exist? 

No, as the furcation may 

approximate the old margin, causing 

the possibility of future problems for the 

furcation and new crown. It is important 

to eliminate any furcation present prior 

to placement of a new restoration. CM 

By removing the old margin and smoothing the 

furcation area, the problem is solved. The operator 

can now place a new margin anywhere he or she 

wishes. 

The flap is sutured just coronal to the bone so as 

not to expose it. The concept of suturing is to try 

to get as much primary closure as possible. Better 

wound healing occurs and less pain is involved with 

primary closure. 

Dr. Daniel Melker is in private practice and can be reached at 727-725-0100. 


Alginate 

Substitutes: 

Rationale 

for Their Use 

– ARTICLE and CLINICAL PHOTOS by 

Leendert Boksman, DDS, FADI, FICD 

and Gregg Tousignant, CDT 

T 

he irreversible hydrocolloid that we commonly refer 

to as alginate is extensively used for study casts, master 

casts and working models for the fabrication of intraoral 

appliances. 1 Alginate is the most common impression 

material used for creating the opposing model for crown 

& bridge, but it has many shortcomings as an ideal impression 

material. The ideal impression material should 

reproduce oral detail accurately; have high tear strength; 

have reasonable working and setting time; be biocompatible; 

be dimensionally stable; allow multiple pours; and 

not be affected in its accuracy by disinfection. 2 

Background on Alginates 

Due to its hydrophilic nature, alginate takes a good impression 

in a moist environment. 3 However, this very feature 

— which is so important to clinicians — creates one 

of the most severe limitations for its use. This property 

creates an impression that is not dimensionally stable due 

to environmental humidity and temperature. 4−7 This feature 

of hydrophilicity also affects the stability of polyethers, 

which can change dimensionally (larger by 30 to 

240 μm, or smaller by 20 to 120 μm) depending on humidity. 

8 Polyether impressions and alginate impressions 

wrapped in moist towels should never be shipped to the 

laboratory in the same polybag because the polyether impression 

can absorb water from the alginate impression 

or its wet wrap. Alginate impressions should immediately 

be poured in dental stone for maximum accuracy because 

of the material’s ability to imbibe or lose moisture. After 

10 minutes of storage time, alginate begins to distort. After 

one to three hours, it cannot be used for many clinical 

purposes, especially fixed prosthodontics (Fig. 1). 9 

The stability of alginates is also affected by the reaction of 

syneresis, in which fibril cross-linking continues, creating 

a contraction with time and an exudation of water. This 

reaction, therefore, necessitates immediate pour-up of the 

alginate. Irreversible hydrocolloids such as alginate can 

be poured up only once because of hydrophilicity. 

Hydrophilicity also creates a monumental problem with 

disinfection of irreversible hydrocolloid, with hundreds 

of research articles looking at types of disinfectants in 

various combinations with a multitude of alginates. These 

investigations show that disinfection can create severe effects 

on dimensional accuracy, with immersion creating 

the greatest inaccuracy, as well as an effect on the surface 

quality of the casts produced. 10−14 Alginate has a low tear 

strength and snags easily, especially in deep undercuts 

and pontic areas. It has a tendency to stick to teeth, with 

possible alginate tears on removal of the alginate. Polishing 

or prophylaxis of the teeth exacerbates the problem, 

preventing the alginate material from wetting the teeth 

and reproducing detail. 15 If the teeth are dried from taking 

one impression, retaking a good, detailed second impression 

of the same arch is impossible. 2 

Alginate Substitutes: Rationale for Their Use57

If one adds the clinical variability 

of the inaccuracy of the amount of 

powder used in the mix (Fig. 2), the 

amount and temperature of the water 

(both which affect thixotropy and 

working time) (Fig. 3), the effects of 

mixing methods on the mechanical 

properties of alginates, 16 the effect of 

type and design of tray on clinical accuracy, 

17,18 the effects of using adhesives 

(Fig. 4) 19,20 , and the exposure to 

hazardous dust, 1,21 it is not surprising 

that alginate substitutes are becoming 

more popular (Table 1, Fig. 5). 

Alginate Substitutes 

Alginate substitutes are low-cost 

polyvinylsiloxanes (PVS) that have 

the same characteristics of higherpriced 

PVS materials used for final 

impressions in fixed prosthodontics. 

Christensen describes these alginate 

substitutes as accurate, clean 

to use (no bowl to clean, no dust), 

flavorless (flavor increases salivation, 

which is not favorable), odorless and 

as having the ability to delay pouring 

or to make additional pours of the 

same impression (Fig. 6). 22 Multiple 

studies have demonstrated that PVS 

is the most dimensionally stable impression 

material 23,24 and has a higher 

tear strength than alginate. Unlike 

alginates, they are not affected by 

disinfection techniques. 25 

The ability to pour these alginate 

substitutes at any time provides a 

whole new window of opportunity 4 

and now allows the clinician to send 

these opposing impressions along with the final crown & 

bridge impression to the laboratory, eliminating the need 

to pour, separate and trim the model in the dental office. 

Not only does this save the office a tremendous amount 

of time and money, but now this process is a billable 

procedure as part of the laboratory fee for the crown & 

bridge case. Currently, most dentists absorb the cost of 

fabricating the opposing model and do not bill it as a 

separate procedure. Because the PVS has better surface 

replication of the opposing dentition, and because the 

variables around mixing the dental stone are more closely 

monitored in the laboratory, the opposing model will be 

much more detailed and accurate. 

Figure 1: Dehydration of the flanges of this alginate 

impression is noticeable 2 minutes after 

taking the impression. 

Figure 3: Every mix of traditional alginate will 

have different thixotropy and working/setting 

time due to variables in water/powder ratio 

and temperature of the water. 

Figure 2: The amount of powder in the measuring 

cup can be highly variable. 

Figure 4: Model derived from alginate impression 

without the use of an adhesive. Note that 

the lower left quadrant has pulled away from 

the tray. 

Alginate Substitutes Currently Available 

COUNTER-FIT 

Clinician’s Choice 

Position Penta Quick 

3M ESPE 

AlgiNot Sybron Dental Specialties/Kerr 

Silgimix 

Sultan Healthcare 

StatusBlue 

Zenith Dental/DMG 

Freealign 

Zhermack 

Algin•X 

Dentsply Caulk 

Table 1 


Figure 5: Alginate substitute (COUNTER-FIT) is injected into a Border- 

Lock ® (Clinician’s Choice) tray lined with a PVS (Affinity Tray Adhesive 

[Clinician’s Choice]) adhesive. 

Figure 6: Internal detail of a COUNTER-FIT impression that has been repoured 

four times. (An alginate should never be poured a second time.) 

Figure 7: Alginate-derived stone models on 

PVS bite registration material show an obvious 

open-bite relationship. 

Figure 8: Alginate-driven stone models on Affinity 

Quick Bite PVS bite registration material 

show inaccurate fit. 

Figure 9: Mounted case from Figure 8 shows 

mismounted open bite. 

Figure 10: COUNTER-FIT−driven stone model on Quick Bite PVS 

shows good interdigitation of the three components. 

Figure 11: Precise mounting of the opposing casts is obvious when using 

matching accuracies in the impression and bite registration materials. 

This creates clinical predictability. 

Alginate Substitutes: Rationale for Their Use59

One of the main driving forces of a change in direction from opposing models produced from alginate to opposing 

models derived from alginate substitutes in fixed prosthodontics is the severe mismatch of accuracy between modern 

bite registration materials and alginate-driven stone models. Boksman 26 looked at PVS bite registration materials and 

the need for extensive occlusal adjustments on crown & bridge prostheses, showing the severe open-bite mounting 

that can result when using a highly accurate PVS bite registration with a poorly detailed alginate-driven stone model 

(Fig. 7). Using PVS for the final impression, for the bite registration and for the opposing models eliminates the dimensional 

mismatch between materials, resulting in more accurate mounting of the case and less clinical necessity for occlusal 

adjustments (Fig. 8−11). 

The surface replication of the casts is also much smoother than models derived from alginate impressions. Even though 

the cost of the PVS alginate substitutes is higher than the irreversible hydrocolloid alginate materials, the impression is 

easier to take due to the thixotropic nature of these materials, the time and cost of pouring up the opposing model can 

be eliminated, the impression can be repoured if the model is broken or chipped, there is increased office efficiency, 

the opposing model is more accurate, the bite registration actually fits, and the time and frustration of adjusting the 

final prosthesis is minimized. These many benefits more than compensate for the extra cost. In addition, the clinician 

can now (in some cases) bill this as part of the laboratory procedure. CM 

References 

1. Pace SL. Polyvinyl impression materials vs. alginate impression materials. Contemp Dental Assisting. Feb 2006:20−23. 

2. Rubel BS. Impression materials: a comparative review of impression materials most commonly used in restorative dentistry. Dent Clin North Am. 2007:51:629−642. 

3. Cohen BI, Pagnillo M, Deutsch AS, et al. Dimensional accuracy of three different alginate impression materials. J Prosthodont. 1995:4:195−199. 

4. Perry R. Using polyvinyl impressions for study models: a case report. Dent Today. Oct 2004:23:106−107. 

5. Chen SY, Liang WM, Chen FN. Factors affecting the accuracy of elastometric impression materials. J Dent. 2004:32:603−609. 

6. Straw J, Iuorno F, Lindauer S. Dimensional stability of Kromopan, an irreversible hydrocolloid impression material. Presented at 32nd Annual Meeting and Exhibition 

of the ADR; March 12-15, 2003; San Antonio, TX. Abstract 0290. http://iadr.confex.com/iadr/2003SanAnton/techprogram/abstract_26049.htm. Accessed 

Feb 3, 2009. 

7. Bayindir F, Yanikoglu N, Duymus Z. Thermal and pH changes, and dimensional stability in irreversible hydrocolloid impression material during setting. Dent Mater J. 

2002:21:200−209. 

8. Kanehira M, Finger WJ, Endo T. Volatization of components from and water absorption of polyether impressions. J Dent. 2006:34:134−138. 

9. Nichols PV. An investigation of the dimensional stability of dental alginates. Sydney, Australia: Faculty of Dentistry, University of Sydney; 2006. http://hdl.handle 

net/2123/1270. Accessed Feb 23, 2009. 

10. Taylor RL, Wright PS, Maryan C. Disinfection procedures: their effect on the dimensional accuracy and surface quality of irreversible hydrocolloid impression 

materials and gypsum casts. Dental Mater. 2002:18:103−110. 

11. Jagger DC, Al Jabra O, Harrison A, et al. The effect of a range of disinfectants on the dimensional accuracy of some impressionmaterials. Eur J Prosthodont 

Restor Dent. 2004;12:154−160. 

12. Machado C, Johnston W, Coste A, et al. Simulated clinical compatibility of disinfectant solutions with alginate impression materials. Presented at: IADR General 

Session & Exhibition; June 28-July 1, 2006; Brisbane, Australia. Abstract 2467. http://iadr.confex.com/iadr/2006Brisb/techprogram/ abstract_82984.htm. Accessed 

Feb 23, 2009. 

13. Muller-Bolla M, Lupi-Pegurier L, Velly AM, et al. A survey of disinfection of irreversible hydrocolloid and silicone impressions in European Union dental schools: 

epidemiologic study. Int J Prosthodont. 2004:17:165−171. 

14. Lu JX, Zhang FM, Chen YM, et al. The effect of disinfection on dimension stability of impressions [in Chinese]. Shanghai Kou Qiang Yi Xue. 2004:13:290−292. 

15. Phoenix RD, Cagna DR, DeFreest CE. Stewart’s Clinical Removable Partial Prosthodontics. 3rd ed. Chicago, IL: Quintessence Publishing; 2003:162−167. 

16. Frey G, Lu H, Powers J. Effect of mixing methods on mechanical properties of alginate impression materials. J Prosthodont. 2005:14:221−225. 

17. Mendez AJ. The influence of impression trays on the accuracy of stone casts poured from irreversible hydrocolloid impressions. J Prosthet Dent. 1985:54:383−388. 

18. Gordon GE, Johnson GH, Drennon DG. The effect of tray selection on the accuracy of elastomeric impression materials. J Prosthet Dent. 1990:63:12−15. 

19. Leung KC, Chow TW, Woo EC, et al. Effect of adhesive drying time on the bond strength of irreversible hydrocolloid to stainless steel. J Prosthet Dent. 

1999:81:586−590. 

20. Smith SJ, McCord JF, Macfarlane TV. Factors that affect the adhesion of two irreversible hydrocolloid materials to two custom tray materials. J Prosthet Dent. 

2002:88:423−430. 

21. Craig RG. Review of dental impression materials. Adv Dent Res. 1988:2:51−64. 

22. Christensen GJ. Ask Dr. Christensen. Dent Econ. March 2008:98:66. 

23. Karthikeyan K, Annapurni H. Comparative evaluation of dimensional stability of three types of interocclusal recording materials: an in vitro study. J Indian 

Prosthodont Soc. 2007:7:24−27. 

24. Boksman L. Eliminating variables in impression-taking. Ontario Dentist. Dec 2005:22−25. 

25. Waranowicz MT, O’Keefe KL. Alginates and alginate substitutes. The Dental Advisor. 2007:24:1−7. 

26. Boksman L. Point of care: how do I minimize the amount of occlusal adjustment necessary for a crown? J Can Dent Assoc. 2005:71:494−495. 

Dr. Len Boksman is adjunct clinical professor at the Schulich School of Medicine and Dentistry and maintains a private practice in London, Ontario, Canada. He is also a 

paid part-time consultant to Clinical Research Dental Inc. and Clinician’s Choice. Contact him at lboksman@clinicalresearchdental.com or 519-641-3066, ext. 292. 

Gregg Tousignant, CDT, is technical support manager for Clinical Research Dental Inc. E-mail him at gtousignant@clinicalresearchdental.com. 

Reprinted by permission of Dentistry Today, ©2009 Dentistry Today. “DOCTOR-TECHNICIAN PERSPECTIVES: Alginate Substitutes: Rationale for Their Use,” by 

Leendert Boksman, DDS, and Gregg Tousignant, CDT: Dentistry Today, Vol. 28, No. 4, 04/09, pp 104−105. 


Patient Product Review 


n the PC world, we are called “Fanboys”: the group of people who love everything Apple puts out. From the iPod 

to the iPhone to the iPad, we are the ones who will even try to make an argument for why AppleTV is useful. We 

are to Apple products what my teenage daughters are to Justin Bieber: obsessed. 

Fortunately, when Apple sells 2 million iPads in the first 60 days you realize that maybe you aren’t insane. I have found 

plenty of things to do with my iPad, and nowadays my Mac laptop stays at work and doesn’t even get dragged home. I 

do 99 percent of my daily activities on the iPad using the intuitive touch screen to flip through e-mails and Web pages. 


Figure 1: This screen shows the patient a tooth 

requiring a crown and illustrates the two most 

common causes: fractured cusp and/or decay. 

Figure 2: This image explains to the patient the 

rough crown prep on the tooth; however, there 

is still tooth structure missing. 

Figure 3: This illustration shows the patient the 

finished build-up and explains how the tooth is 

now strong enough to handle the load of having 

a crown on top; the build-up insulates the 

pulp to help prevent endo. 

Figure 4: The patient can see how the crown 

slides into place on our ideal crown prep. Keep 

in mind these are still frames that are actually 

animated on the iPad; it is not static as it appears 

here. 

Figure 5: This animation shows the patient 

the beautifully finished porcelain crown with 

perfect margins and healthy gingiva — the kind 

of stuff we see all day long! 

I was convinced I would never have a need to bring my iPad to work until I had the opportunity to use the Dental 

Demo Suite at the May 2010 CDA meeting in Anaheim, Calif. Finally, I was going to be able to use my love for Apple 

products to be productive at work! 

Dental Demo Suite is a simple, effective patient-education program sold through the Apple App Store. Gone are the 

days of me trying to draw on the bracket table paper to explain an abscess, or trying to explain why we have to build up 

a tooth just so we can grind it down again. In fact, that has been one of my favorite animations; I love having a straightforward 

way to illustrate why build-ups are necessary. Unlike other patient-education methods in which the patient 

has to watch a DVD, this is truly interactive as you (or your assistant or your hygienist) use the animations to educate 

and answer questions regarding treatment. As you place your finger on the slider, it allows you to move backward and 

forward to answer questions about specific aspects of the proposed treatment. Many patients have taken it out of my 

hands to activate the animation themselves. There is no doubt that educated patients make better purchase decisions. 

You can generate treatment plans, e-mail your patients directly from the program, and even add your own images to 

the ones that come standard in the program. I also love that once you buy the program it is yours; there is no annual 

fee, subscription fee or update fee. CM 

For more information on Dental Demo Suite GP, call 800-631-2021 or visit the Apple App Store or dentaldemosuite.com. 

Dr. DiTolla’s Patient Product Review63

“That damn lab — 

I wrote freestanding 

pontic, not potty.” 

Rick J. Meyers, DDS 

Phoenix, Ariz. 

1st place winner of $500 lab credit 

“This was the cheapest 

porcelain I could find!” 

Mark C. Albritton, DDS 

Nederland, Texas 

2nd place winner of $100 lab credit 

INTRAoral 2000 

“Well, I think I found the 

source of your bad breath.” 

Herbert Friedman, DDS 

Havre de Grace, Md. 

3rd place winner of $100 lab credit 

Honorable Mention 

“I guess I’ll be sending your impression to Glidewell Lavatory.” 

Joshua M. Haremza, DDS 

Palmyra, N.Y. 

“Your new porcelain crown is the whitest shade available!” 

Jeffrey Berkowitz, DDS, PC 

Ossining, N.Y. 

The Chairside ® 

Caption Contest Winners! 

Congratulations to winners of the Vol. 5, Issue 2 Chairside Caption Contest. The winning captions were chosen from hundreds of entries 

e-mailed and submitted online to Chairside magazine when asked to add a caption to the illustration above. Winning entries were judged 

on humor and ingenuity. 


“It’s a bur ... it’s a post ... it’s Super (Cheap) Doc!” 

The Chairside ® 

Caption Contest 

Send your caption for the above photo along with your name and city of practice to: chairside@glidewelldental.com. By submitting 

a caption, you authorize Chairside magazine to print your name in a future issue or on our website. You may also submit your entry 

online at chairsidemagazine.com. 

The winner of this issue’s Caption Contest will receive $500 in Glidewell credit or $500 credit toward his or her account. The secondand 

third-place winners will each receive $100 in Glidewell credit or $100 credit toward their accounts. Entries must be received by 

August 23, 2010. The winners will be announced in the fall issue of Chairside.

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