State of the art implant placement and restoration ... - Nobel Biocare

TechnologyState of the art implant placement andrestoration through guided techniques:An ‘all-on-4’ clinical reportBy Martin Marcus DDS, Russell Baer DDS, Nelson Lo DDS - UniversityAssociates in Dentistry, Dental Implant Institute of Chicago, Chicago, IllinoisImplant dentistry has become a well provenaccepted standard of care for the singletooth, multiple missing teeth, as well as thefully edentulous arch of teeth. Constant changesare rapidly improving our ability to clinicallytreat patients in a more expeditious, efficientand less invasive manner. Technologies usingCBCT (cone beam computerized technology)3-D imaging, computer generated planningsoftware, guided surgery and immediate functionhave benefited our patients with reducedtreatment times, minimally invasive and simplifiedsurgical techniques, reduction of postsurgicaldiscomfort and the immediate placementof a fixed restoration.The guided implant surgical and prosthetictechnique for the All on 4 restoration of anedentulous arch has gained greater acceptanceand success 1 . Its benefits are many:• The ability to rehabilitate the completelyedentulous jaw with a minimum of bone volumeand avoiding in most situations bonegrafting procedures 1 .• Flapless surgery which allows for the patientto experience less surgical trauma, painor swelling 2 .• Strategically placed implants, 2 posteriorlyand 2 anteriorly, with good anchorage haveshown very successful outcomes 3, 4 .• Angulations of the implants allows for longerimplants to be placed with cortical boneanchorage. Greater anterior-posterior spreadof implants creates an ability to restore teethback to the first molar region with the reductionof cantilever effects 5, 6 .• The prosthesis allows for the re-establishmentof vertical dimension most patients havelost to either bone loss due to periodontal diseaseor existing old dentures.• Primary immediate implant stabilizationreducing the mechanical load by implantsplinting 7, 8 .• An immediate function fixed restoration atthe time of surgery due to implant stability 9 .• The immediately loaded restoration allowsan easier transition for patients from a removableto a fixed restorative state.• Simplifies the procedure for the clinician.Clinical reportPlanningA 70 year old woman presented with a maxillarydenture. The patient has been edentulousin the upper jaw for over 10 years (Fig.1). Shehas worn several different sets of dentures duringthat period of time. A preliminary evaluationof her dental and medical history wasobtained. Her medical history presents withno significant contraindications for implantsurgery. A treatment plan was devised utilizingguided implant surgery and the All on 4(Nobel Biocare) protocols.The upper denture was relined in order to fitintimately with the tissue, at a corrected occlusalvertical dimension and with a pleasing, acceptable,esthetic alignment. This will duplicateas a radiographic template.Multiple 2-mm holes were placed into thedentures at different levels and in areas bothbuccally and palatally. These holes were filledwith gutta percha as radio-opaque markers.(Fig. 2) An occlusal record was then taken usingvinyl polysiloxane at the appropriate centricand vertical dimensions. This allowed thepatient to hold the radiographic template inposition during the CBCT scan and preventmovement.Our patient was now ready for a CBCT(Gendex CB-500; DENTSPLY) scan. CBCT allowsviews of different objects at different densitiesin a 3D view. We can visualize availablebone for implant placement, as well as pertinentanatomical structures such as the maxillarysinuses, the mandibular inferior alveolarnerve canal, soft tissue thickness and tooth positionrelative to the underlying bone 10 .A double scan technique was used 11 . Thefirst scan was of the patient with her denture(radiographic template) and the interocclusalrecord. (Fig.3) The second scan was of the dentureonly.The CBCT data was then formatted andtransferred into a 3-demensional implant planningsoftware program (Procera CAD Design;Nobel Biocare). Implant positions and sizes,as it relates to bone availability and associatedvital structures, can be digitally evaluated andplaced. Super imposing the two sets of scansallowed us to correlate the correct planned implantposition in relation to the position of thedenture teeth on the prosthesis. (Fig.4)After the plan was completed, the data wastransferred to a milling center to fabricate astereolithography surgical guide and duplicatedenture.(Fig.5) This guide will: 1) at the timeof surgery, direct the placement of implants intothe identical positions as planned for a flaplesssurgical approach 12 and 2) allow for creatinga cast from which the interim, immediateprosthesis will be created. (Fig.6) The duplicatedenture gives the technician the ability tomount the cast and shows tooth position to beduplicated into an all acrylic fixed hybrid interimprostheses. (Fig. 7) A new silicone centricocclusal record was created with the surgicalguide and opposing arch. This allows properseating of the guide at the time of surgery.SurgeryAfter all our pre-surgical diagnostics and planningwere completed guided implant surgerywas performed. Initially appropriate pre-surgicalmedications were given which includedantibiotics, analgesics and an antimicrobialrinse.Local anesthetics were given ie. lidocaineand bupivacaine and the surgical guide inserted.Biting on the interocclusal record for1 – 2 minutes allowed for tissue displacementinsuring a more positive position of the guideto the planning data. Positioning and seatingof the guide was confirmed. While the patientremained closed on the interocclusal recordour initial step was to place the 3 pre-plannedhorizontal stabilization pins. This secured theguide. The interocclusal record was removed,exposing the surgical sites of the guide.The first osteotomy was prepared, choosingone of the anterior positions. Appropriate sequencingof the tissues punch, drilling guidesand twist drills were used according to themanufacturer’s directions (NobelGuide; NobelBiocare). Once the osteotomy was completed,the pre-planned implant type, length and sizewere placed and a template abutment inserted.This now provided the guide with additionalstability from a vertical direction as well. The46 Implant practice August 2009 Volume 2 Number 3

TechnologyFigure 1 Figure 2 Figure 3Figure 4 Figure 5 Figure 6Figure 7 Figure 8 Figure 9remaining three implant osteotomy sites werethen prepared using the same sequential drillingprotocols and the appropriate implantswere placed. (Fig. 8)After implant placement the surgical guidewas removed and the 2 anterior straight multiunitabutments ( Multiunit abutment; NobelBiocare) were placed first, followed by theposterior 30 degree angled abutments (30 degreeMultiunit abutment; Nobel Biocare) usinga laboratory fabricated custom jig.(Fig. 8)The all acrylic hybrid prosthesis was tried infor fit and confirmed by radiographic evaluation.Occlusion and vertical dimension wereevaluated and minor adjustments made asneeded. The prosthesis was screwed in, accessholes covered and immediate functionobtained.(Fig.10)Post-operative instructions regarding hygienemaintenance, soft diet and continuedantibiotics (daily for 1 week), anti-inflammatory(ibuprofen 600mg. 3 times a day for 3days) and antimicrobial (chlorhexidine rinse,daily for 1 week) were prescribed. Any othermedications thought to be necessary, such as anarcotic for pain, would be considered at thistime as well.RestorativeAfter 3 months of osseointegration the restorationof a titanium reinforced fixed hybridprosthesis (Procera Implant Bridge; NobelBiocare) was created. The interim prosthesiswas removed, tissue and implant site inspectionfor osseointegration were evaluated, andthe following sequence of appointments werenecessary for the completion of the final restoration.1. Custom tray impression using impressiontransfers for the positional relationship of theimplants to the ridge and each other. (Fig 11)2. Verification jig to identify that the implantson the master cast are in the identical positionas they are in the mouth. (Fig. 12)3. Bite block records to measure the verticaland centric relation positions.4. Wax try-in to ensure the esthetics, toothposition, phonetics and occlusion. Also thisidentified the spacial relationship betweenthe correct tooth position, the ridge and theimplant abutments to create a custom milledAugust 2009 Volume 2 Number 3 Implant practice 47

TechnologyFigure 10 Figure 11 Figure 12Figure 14 Figure 15Figure 13titanium bar that was milled and fit within theparameters of the prosthesis.5. Try-in of the custom milled titanium retentionbar along with the transfer of the tooth setup for final evaluation of fit, esthetics and function(phonetics and occlusion).(Fig12)6. Delivery of the final prosthesis, minor occlusaladjustments, torquing the retention screwsto 15 Ncm. and restoring the screw accessholes.(Fig14)7. Radiographic confirmation of the fit of theprosthesis to the implant abutments, implantplacement and integration.(Fig.15)SummaryTechnological advancements continue to revolutionizeour abilities to treat our patients ina more efficient and less invasive manner.Through CBCT dual scan data visualization ofavailable bone, anatomical issues that may beencountered during surgery, soft tissue thicknessand prosthetic tooth position may be revealed.3-D virtual planning allows us to diagnosticallyplan implant sites, develop surgicalguides to transfer that information intraorallyand create a prefabricated, immediate functionprosthesis before the patient is even inour dental chair. By using surgical guides forimplant placement the implants may be placedthrough a minimally invasive flapless procedure,quickly, predictably and with a low levelof complications. This minimizes the patient’spain, time and stress. Restoratively, we are ableto bring our patients from a removable dentureREFERENCES1. MaloP., NobreM.,Lope,A. The Use of Computer-Guided Flapless Implant Surgery and Four ImplantsPlaced in Immediate Function to Support a FixedDenture: Preliminary Results After a Mean FollowupPeriod of Thirteen Months. Journal of ProstheticDentistry 2007 Volume 97 Issue 62. CampelLD, CamaraJR. Flapless Implant Surgery;A 10-year Clinical Retrospective Analysis. Int JournalOral Maxillofacial Implants 2002 17:271-63. BranemarkPI, SvenssonB, van SteenbergheD.TenyearSurvival Rates of Fixed Prostheses on Four to SixImplants Ad Modum Branemark in Full Edentulism.Clin Oral Implants Res 1995; 6:227-314. Mal,P, RangertB, NombreM. ‘All on Four’Immediate Function Concept with BranemarkSystem Implants for Completely Edentulous Maxilla:A 1 Year Retrospective Clinical Study. Clin ImplantDent Relat Res 2003:7 Supplement 1:588-945. AparicioC, PeralesP, RangertB. Tilted Implants asan Alternative to Maxillary Sinus Grafting: A Clinical,Radiographic and Periotest Study. Clin Implant DentRelat Res 2001;3:39-496. KrekamanovL, KahanM, RangertB, Lindstrom,H.Tilting of Posterior Mandibular and MaxillaryImplants of Improved Prosthesis Support. Int Journalof Oral Maxillofacial Implants 2000;15:405-147. MortonD, JaffinR, WeberHP. ImmediateRestoration and Loading of Dental Implants:Clinical; Considerations and Protocols. Int Journal ofto a functioning fixed prosthesis immediately.Considering the advantages and benefits ofimplant placement and restoration throughguided techniques, we can recommend this asa viable alternative to treatment for rehabilitationof the edentulous jaws.IOral Maxillofacial Implants 2004;19 Supplemental1:103-88. AttardNJ, ZarbGA. Immediate and Early ImplantLoading Protocols: A Literature Review of ClinicalStudies. Journal of Prosthetic Dentistry 2005;94:242-589. SchnitmanDA, WohrlePS, RubensteinJE et al.Branemark Implants Immediately Loaded withFixed Prosthesis at Implant Placement: Ten YearResults. Int Journal Oral Maxillofacial Implants1997;12:495-50310. SonickM, AbrhamsJ, FaiellaR. A Comparisonof the Accuracy Of Periapical, Panoramic, andComputerized Tomographic Radiographs in Locatingthe Mandibular Canal. Int Journal Oral MaxillofacialImplants. 1994;9(4);455-46011. Van SteenbergheD, NaertI, AnderrsonM,Brajnovic I, Van CleynenbreugelJ, SuetensP. ACustom Template and Definitive Prosthesis AllowingImmediate Loading in the Maxilla: A ClinicalReport Int Journal of Oral Maxillofacial Implants2002;17:663-7012. Van SteenbergheD, GlauserR, BlombackU, et al.A Computed Tomographic Scan-derived CustomizedSurgical Template and Fixed Prosthesis for FlaplessSurgery and Immediate Loading of Implants in FullyEdentulous Maxillae: A Prospective MulticenterStudy. Clin Implant Dent Relat Res. 2005;7 (Suppl1):S111-S12048 Implant practice August 2009 Volume 2 Number 3