The current status of laser applications in dentistry - Wiley Online ...

REVIEW 

The current status of laser applications in dentistry 

LJ Walsh* 

Abstract 

A range of lasers is now available for use in 

dentistry. This paper summarizes key current and 

emerging applications for lasers in clinical practice. 

A major diagnostic application of low power lasers 

is the detection of caries, using fluorescence elicited 

from hydroxyapatite or from bacterial by-products. 

Laser fluorescence is an effective method for 

detecting and quantifying incipient occlusal and 

cervical carious lesions, and with further refinement 

could be used in the same manner for proximal 

lesions. Photoactivated dye techniques have been 

developed which use low power lasers to elicit a 

photochemical reaction. Photoactivated dye 

techniques can be used to disinfect root canals, 

periodontal pockets, cavity preparations and sites of 

peri-implantitis. Using similar principles, more 

powerful lasers can be used for photodynamic 

therapy in the treatment of malignancies of the oral 

mucosa. Laser-driven photochemical reactions can 

also be used for tooth whitening. In combination 

with fluoride, laser irradiation can improve the 

resistance of tooth structure to demineralization, 

and this application is of particular benefit for 

susceptible sites in high caries risk patients. Laser 

technology for caries removal, cavity preparation 

and soft tissue surgery is at a high state of 

refinement, having had several decades of 

development up to the present time. Used in 

conjunction with or as a replacement for traditional 

methods, it is expected that specific laser 

technologies will become an essential component of 

contemporary dental practice over the next decade. 

Key words: Lasers, dental applications, débridement, 

photosensitization, resin curing. 

(Accepted for publication 6 February 2003.) 

INTRODUCTION 

The past decade has seen a veritable explosion of 

research into the clinical applications of lasers in dental 

practice, and the parallel emergence of organizations to 

support laser dentistry with an international focus. 

Once regarded as a complex technology with limited 

uses in clinical dentistry, there is a growing awareness 

*Professor of Dental Science, School of Dentistry, The University of 

Queensland. 

Australian Dental Journal 2003;48:(3):146-155 

of the usefulness of lasers in the armamentarium of the 

modern dental practice, where they can be used as an 

adjunct or alternative to traditional approaches. 

Traditionally, lasers have been classified according to 

the physical construction of the laser (e.g., gas, liquid, 

solid state, or semiconductor diode), the type of 

medium which undergoes lasing (e.g., Erbium: Yttrium 

Aluminium Garnet (Er:YAG)) (Table 1), and the degree 

of hazard to the skin or eyes following inadvertent 

exposure (Table 2). Lasers have been available 

commercially for use in dental practice in Australia 

since 1990, and the currently available systems 

represent a high state of technical refinement in terms 

of both performance and user features. 

The purpose of this paper is to provide an overview 

of various laser applications which have been 

developed for dental practice, and to discuss in more 

detail several key clinical applications which are 

attracting a high level of interest. 

Diagnostic laser applications 

Low power laser energy has found numerous uses in 

diagnosis, both in clinical settings (Table 3) and in 

dental research (Table 4). By way of background, low 

power lasers operate typically at powers of 100 

milliwatts or less, and may produce energy in the visible 

spectrum (400-700nm wavelength), or in the ultraviolet 

(200-400nm), or near infrared regions (700-1500nm). 

At the present time, there are few purpose built low 

power lasers for the middle infrared (1500-4000nm) or 

far infrared regions (4000-15000nm). Rather, lasers 

operating in the middle and far-infrared regions are 

used in health care primarily for hard and soft tissue 

procedures. 

Laser fluorescence systems for detection of dental 

caries have been particularly popular in Australia. The 

original technique employed visible blue light from the 

argon laser, relying on the lack of fluorescence from 

carious enamel and dentine to demonstrate the 

presence of the lesion. Subsequent development of the 

technique allowed visible red laser light from a 

semiconductor diode laser to be used to elicit 

fluorescence from bacterial deposits, and from calculus. 

Combining a detection system with a therapeutic laser 

has allowed automated removal of subgingival calculus 

146 Australian Dental Journal 2003;48:3.

Table 1. Common laser types used in dentistry 

Laser type Construction Wavelength(s) Delivery system(s) 

Argon Gas laser 488, 515nm Optical fibre 

KTP Solid state 532nm Optical fibre 

Helium-neon Gas laser 633nm Optical fibre 

Diode Semiconductor 635, 670, 810, 

830, 980nm 

Optical fibre 

Nd:YAG Solid state 1064nm Optical fibre 

Er,Cr:YSGG Solid state 2780nm Optical fibre 

Er:YAG Solid state 2940nm Optical fibre, 

waveguide, 

articulated arm 

CO2 Gas laser 9600, 10600nm Waveguide, 

articulated arm 

from teeth and dental implants, a point discussed in 

further detail below. 

For detection of dental caries in pits and fissures, 

laser fluorescence offers greater sensitivity than 

conventional visual and tactile methods. 1,2 The 

technique is also well suited to smooth surface lesions 

on cervical surfaces of teeth, 3,4 and to recognition of 

caries beneath clear fissure sealants. 5 Detection of 

proximal lesions is technically more difficult, and in 

this setting, argon laser-induced fluorescence offers a 

valuable adjunct to conventional methods. 6-9 The 

differential water content of early fissure caries and 

sound occlusal enamel has also led to the development 

of methods using the carbon dioxide laser to reveal 

such lesions, 10-12 and to modify the fissure system to 

increase resistance to future carious attack. 11 

Two key advantages of laser-based systems are their 

high sensitivity, and the lack of attendant risks of 

ionizing radiation. This has allowed their frequent use 

for monitoring lesions of dental caries and dental 

erosion. 13-16 Extension of the principles of laser 

fluorescence from the visible to the near infrared and 

terahertz portions of spectrum opens the possibility for 

more detailed analysis of the internal composition of 

the tooth. 17 Moreover, the use of dyes in conjunction 

with laser fluorescence holds promise for using the 

method for delineating cavitated from non-cavitated 

lesions in sites of poor clinical access, such as 

approximal surfaces. 18,19 

Bacterial porphyrins in dental calculus give a strong 

fluorescence signal, 20 which can be used to control 

lasers used for scaling. The same principle could be 

applied to lesions of dental caries, where a targeting 

laser could induce fluorescence and provide feedback to 

Australian Dental Journal 2003;48:3. 

Table 2. Laser classification according to potential 

hazards 

Class Risk Example 

I Fully enclosed system Nd:YAG laser welding system 

used in a dental laboratory 

II Visible low power laser Visible red aiming beam of a 

protected by the blink reflex surgical laser 

IIIa Visible laser above 

1 milliwatt 

No dental examples 

IIIb Higher power laser unit Low power (50 milliwatt) 

(up to 0.5 watts) which diode laser used for 

may or may not be visible. 

Direct viewing hazardous 

to the eyes 

biostimulation 

IV Damage to eyes and skin All lasers used for oral surgery, 

possible. Direct or indirect whitening, and cavity 

viewing hazardous to 

the eyes 

preparation 

the user as to the presence of residual bacteria (i.e., the 

presence of infected carious dentine), and could also 

control the action of a pulsed laser to achieve 

automated caries removal. There are already data on 

the spectral changes which occur during infrared laser 

treatment of enamel and dentine 21,22 which could 

similarly be applied clinically when assessing the 

presence or absence of carious tooth structure during 

laser-based cavity preparation. 

Photoactivated dye disinfection using lasers 

Low power laser energy in itself is not particularly 

lethal to bacteria, but is useful for photochemical 

activation of oxygen-releasing dyes. Singlet oxygen 

released from the dyes causes membrane and DNA 

damage to micro-organisms. The photoactivated dye 

(PAD) technique can be undertaken with a range of 

visible red and near infrared lasers, and systems using 

low power (100 milliwatt) visible red semiconductor 

diode lasers and tolonium chloride (toluidine blue) dye 

are now available commercially (Fig 1). The initial 

work which demonstrated the PAD technique used 

helium-neon lasers. 23 However, such units have been 

surpassed with high efficiency diode lasers which 

operate at the same wavelength. 

The PAD technique has been shown to be effective 

for killing bacteria in complex biofilms, such as 

subgingival plaque, which are typically resistant to the 

action of antimicrobial agents. 24-26 It can be used 

effectively in carious lesions, since visible red light 

transmits well across dentine, 27 and can be made 

species-specific by tagging the dye with monoclonal 

Table 3. Diagnostic laser applications for clinical practice 

Argon 

488nm 

Helium-neon 

633nm 

Diode 

633nm 

Diode 

655nm 

CO2 10600nm 

Laser fluorescence detection of dental caries ✔ ✔ 

Laser fluorescence detection of subgingival calculus ✔ 

Detection of fissure caries lesions by optical changes ✔ 

Laser doppler flowmetry to assess pulpal blood flow ✔ ✔ 

Scanning of phosphor plate digital radiographs ✔ 

Scanning of conventional radiographs for teleradiology ✔ 

147

Table 4. Diagnostic laser applications used as research tools 

Nd:YAG Er:YAG Argon Helium-neon Diode 

1064nm 2940nm 488 and 515nm 633nm 633 and 670nm 

Raman spectroscopic analysis of tooth structure ✔ 

Terahertz imaging of internal tooth structure ✔ 

Breakdown spectroscopic analysis of tooth structure ✔ ✔ 

Confocal microscopic imaging of soft and hard tissues ✔ 

Flow cytometric analysis of cells and cell sorting ✔ 

Profiling of tooth surfaces and dental restorations ✔ ✔ 

antibodies. 28 Photoactivated dye can be applied 

effectively for killing Gram-positive bacteria (including 

MRSA), Gram-negative bacteria, fungi and viruses. 29,30 

Major clinical applications of PAD include 

disinfection of root canals, periodontal pockets, deep 

carious lesions, and sites of peri-implantitis. 31,32 In such 

locations, PAD does not give rise to deleterious thermal 

effects, 33 and adjacent tissues are not subjected to 

bystander thermal injury. Photoactivated dye treatment 

does not cause sensitization and killing of adjacent 

human cells such as fibroblasts and keratinocytes. 34 

Neither the dye nor the reactive oxygen species 

produced from it are toxic to the patient. Tolonium 

chloride is used in high concentrations for screening 

patients for malignancies of the oral mucosa and 

oropharynx, 35,36 and does not exert toxic effects at the 

low concentrations used in the PAD technique. 

Moreover, residual reactive oxygen species are rapidly 

dealt with by the enzyme catalase, which is present in 

all tissues and in the peripheral circulation, 37 and by 

lactoperoxidase, which is a normal component of 

saliva. 

Photodynamic therapy 

A more powerful laser-initiated photochemical 

reaction is photodynamic therapy (PDT), which has 

been employed in the treatment of malignancies of the 

oral mucosa, particularly multi-focal squamous cell 

carcinoma. As in PAD, laser-activation of a sensitizing 

dye in PDT generates reactive oxygen species. These in 

Fig 1. Laser system for photo-activated dye therapy, which uses a 

diode laser (635nm) and tolonium chloride dye (SaveDent, Asclepion 

Meditec, Fife, UK). 

turn directly damage cells and the associated blood 

vascular network, triggering both necrosis and 

apoptosis. 38 

Of interest, while direct effects of PDT destroy the 

bulk of tumour cells, there is accumulating evidence 

that PDT activates the host immune response, and 

promotes anti-tumour immunity through the activation 

of macrophages and T lymphocytes. 37 For example, 

there is direct experimental evidence for photodynamic 

activation of the production of tumour necrosis factoralpha, 

39 a key cytokine in host anti-tumour immune 

responses. 

Clinical studies have reported positive results for 

PDT treatment of carcinoma-in-situ and squamous cell 

carcinoma in the oral cavity, with response rates 

approximating 90 per cent. 40,41 The treated sites 

characteristically show erythema and oedema, followed 

by necrosis and frank ulceration. The ulcerated lesions 

typically take up to eight weeks to heal fully, and 

supportive analgesia is required in the first few weeks. 

Other than short-term photosensitivity, the treatment is 

tolerated well. 39 

Other photochemical laser effects 

The argon laser produces high intensity visible blue 

light (488nm) which is able to initiate photopolymerization 

of light-cured dental restorative 

materials which use camphoroquinone as the 

photoinitiator. 42-44 The temperature increase at the level 

of the dental pulp is much less with argon laser curing 

than when conventional quartz tungsten halogen lamp 

units are used. 45,46 Argon laser radiation is also able to 

alter the surface chemistry of both enamel and root 

surface dentine, 47,48 which reduces the probability of 

recurrent caries. This clinical benefit is arguably more 

important than the reduced curing time and improved 

depth of cure achieved with the argon laser. 

A further photochemical effect produced by high 

intensity green laser light is photochemical bleaching 

(Table 5). This effect relies upon specific absorption of 

a narrow spectral range of green light (510-540nm) 

into chelate compounds formed between apatites, 

Table 5. Laser-enhanced tooth whitening 

Argon KTP Diode CO 2 

515nm 532nm 810-980nm 10600nm 

Photochemical bleaching ✔ ✔ 

Photothermal bleaching ✔ ✔ 


Fig 2. KTP laser photochemical bleaching. A. Initial clinical 

appearance of the dentition in a 9-year-old patient with intense 

discolouration of the incisor teeth caused by prolonged childhood 

illnesses and associated medications. B. The situation immediately 

after three 60-minute appointments of power bleaching using a 

conventional quartz tungsten halogen curing lamp and 35 per cent 

hydrogen peroxide gel. The incisal enamel shade has improved 

somewhat, but the areas of discolouration at the gingival third are 

unchanged. The arrow indicates a residue of the protective gingival 

dam. C. Clinical appearance immediately after one session of 

photochemical bleaching using the KTP laser and proprietary 

alkaline hydrogen peroxide (Smartbleach ®) gel. The laser treatment 

was targeted to the gingival third. The patient and her parents were 

pleased with the immediate post-operative result and did not request 

any additional treatment. 

porphyrins, and tetracycline compounds. 49 The argon 

laser (515nm) and potassium titanyl phosphate (KTP) 

laser (532nm) can both be used for photochemical 

bleaching, since their wavelengths approximate the 

absorption maxima of these chelate compounds (525- 

530nm). 50 Argon and KTP lasers can achieve a positive 

result in cases which are completely unresponsive to 

conventional photothermal ‘power’ bleaching (Fig 2). 

Laser applications in the dental laboratory 

There is a range of laboratory-based laser 

applications (Table 6). Laser holographic imaging is a 

well established method for storing topographic 

information, such as crown preparations, occlusal 

tables, and facial forms. The use of two laser beams 

allows more complex surface detail to be mapped using 

interferometry, 51,52 while conventional diffraction 

gratings and interference patterns are used to generate 

holograms and contour profiles. 53-56 

Laser scanning of casts can be linked to 

computerized milling equipment for fabrication of 

restorations from porcelain and other materials. An 

alternative fabrication strategy is to sinter ceramic 

materials, to create a solid restoration from a powder 

of alumina or hydroxyapatite. 57 The same approach can 

be used to form complex shapes from dental wax and 

other materials which can be sintered, such that these 

can then be used in conventional ‘lost wax’ casting. A 

variation on this theme is ultraviolet (helium-cadmium) 

laser-initiated polymerization of liquid resin in a 

chamber, to create surgical templates for implant 

surgery and major reconstructive oral surgery. These 

templates can be coupled with laser-based positioning 

systems for complex reconstructive and orthognathic 

surgical procedures. 

Laser procedures on dental hard tissues 

Cavity preparation using lasers has been an area of 

major research interest since lasers were initially 

developed in the early 1960s. At the present time, 

several laser types with similar wavelengths in the 

middle infrared region of the electromagnetic spectrum 

are used commonly for cavity preparation and caries 

removal. The Er:YAG, Er:YSGG and Er,Cr:YSGG lasers 

operate at wavelengths of 2940, 2790, and 2780nm, 

respectively. These wavelengths correspond to the peak 

absorption range of water in the infrared spectrum 

(Fig 3), although the absorption of the Er:YAG laser 

(13,000cm -1 ) is much higher than that of the Er:YSGG 

(7000cm -1 ) and Er,Cr:YSGG (4000cm -1 ) 58-60 Since all 

three lasers rely on water-based absorption for cutting 

enamel and dentine, the efficiency of ablation 

(measured in terms of volume and mass loss of tooth 

structure for identical energy parameters) is greatest for 

the Er:YAG laser. 58,60 

These laser systems can be used for effective caries 

removal and cavity preparation without significant 

thermal effects, collateral damage to tooth structure, or 

patient discomfort. 61-64 Normal dental enamel contains 

sufficient water (approximately 12 per cent by volume) 

that a water mist spray coupled to an Er-based laser 

Australian Dental Journal 2003;48:3. 149

Table 6. Laser applications in the dental laboratory 

Helium neon 

633nm 

Diode 

635nm 

Nd:YAG 

1064nm 

CO2 10600nm 

Helium-Cadmium 

300nm 

Scanning of models for orthodontics or holographic storage ✔ ✔ 

Scanning of crown preparations for CAD-CAM ✔ ✔ 

Welding of metals (Co:Cr, titanium) ✔ 

Sintering of ceramics ✔ 

CAD-sintering fabrication ✔ 

CAD-polymer fabrication of splints or surgical models ✔ 

Cutting of ceramics ✔ 

system can achieve effective ablation at temperatures 

well below the melting and vapourization temperatures 

of enamel. 61 Er-based dental lasers can also be used to 

remove resin composite resin and glass-ionomer cement 

restorations, and to etch tooth structure (Fig 4). 

A characteristic operating feature of Er-based laser 

systems is a popping sound when the laser is operating 

on dental hard tissues. Both the pitch and resonance of 

this sound relate to the propagation of an acoustic 

shock wave within the tooth, and vary according to the 

presence or absence of caries. This feature assists the 

user in determining that caries removal is complete. 66 In 

contrast to the popping sound during caries removal, 

one current generation Er,Cr:YSGG laser system creates 

a loud snapping sound even when not in contact with 

any structure in the mouth. This seeming paradox can 

be explained by an effect termed ‘plasma de-coupling’ 

of the beam, in which incident laser energy heats the air 

and water directly in front of the laser handpiece. In the 

Er,Cr:YSGG laser, this is done intentionally in order to 

deliver energy onto the rear surface of atomized water 

molecules, with the aim of accelerating them to a higher 

speed (so-called ‘HydroKinetic cutting’). 67 Detailed 

studies of the cutting mechanisms of Er:YAG and 

Er,Cr:YSGG lasers have revealed that the mechanism 

by which enamel is removed is basically the same for 

both laser systems, namely explosive subsurface 

expansion of interstitially trapped water. 65 The same 

investigations also failed to show Er,Cr:YSGG laser 

cutting of a variety of materials which were free of 

water, which the authors stated was ‘contradictory to 

the existence of the hydrokinetic phenomenon’. 65 

14000 

12000 

10000 

8000 

6000 

4000 

2000 

Er,Cr:YSGG 

Er:YAG 

0 

2.6 2.65 2.7 2.75 2.8 2.85 2.9 2.95 3 3.05 3.1 3.15 3.2 3.25 3.3 

Fig 3. The absorption curve of water in the middle infrared region. 

Data on the vertical axis are units of absorption, while the horizontal 

axis shows wavelength in micrometers. The plot shows the position 

of two laser wavelengths used for cavity preparation: Er,Cr:YSGG 

2.78 micrometers, and Er:YAG 2.94 micrometers. The figure is based 

on data from reference 59. 

An important theoretical extension to the principle 

of water-based laser ablation of tooth structure is the 

recently described effect of ‘laser abrasion’, in which 

Er:YAG laser energy is used to accelerate the movement 

of particles of sapphire 30-50 micrometers in diameter 

in aqueous suspension. As in air abrasion, the impact of 

these particles causes brittle splitting, resulting in tooth 

substance removal. In the laser abrasion method, high 

speed photography has documented particle velocities 

in the range of 50-100 metres per second, which enable 

a rate of enamel removal ‘higher than that of high speed 

turbines’ with a very low volume of abrasive particles. 68 

This technique could be employed with current 

generation lasers once a suitable dispensing system for 

the suspension of particles has been developed. As well 

as the potential of even more rapid cutting rates than 

conventional rotary instrumentation, laser abrasion 

offers the promise of laser-based cutting of structures 

which are not otherwise amenable to this, such as 

ceramic restorations. 

Intensive research over the past three decades on 

other non-Erbium laser-based cavity preparation 

systems has yet to be translated to direct clinical 

application. To date, alternative laser systems, 

including super-pulsed CO2, Ho:YAG, Ho:YSGG, 

Nd:YAG, Nd:NLF, diode lasers and excimers, have not 

proven feasible for use for cavity preparation in general 

practice settings. 

Other than caries removal, this is a range of other 

well established laser hard tissue procedures include 

desensitization of cervical dentine (using Nd:YAG, 

Er:YAG, Er,Cr:YSGG CO2, KTP, and diode lasers), 

laser analgesia (using Nd:YAG, Er:YAG, and 

Er,Cr:YSGG lasers), laser-enhanced fluoride uptake 

(using Er:YAG, Er,Cr:YSGG, CO2, argon, and KTP 

lasers). Furthermore, there is a considerable range of 

periodontal procedures (Table 7), and endodontic 

procedures (Table 8) which can be undertaken with 

lasers as an alternative to conventional approaches. 

Soft tissue laser procedures 

There are numerous soft tissue procedures which can 

be performed with lasers. 69-71 Two key features of these 

are reduced bleeding intra-operatively and less pain 

post-operatively compared to conventional techniques 

such as electrosurgery. The degree of absorption in key 

tissue components dictates the type of effect gained by 

the laser on soft tissues, and in this regard the content 

of water and haemoglobin in oral tissues is important 


Fig 4. Restorative procedures using the Er:YAG laser, in anxious dental patients, without local anesthesia. The Er:YAG laser was used with a 

non-contact handpiece. A. Pre-operative appearance of a 22-year-old male with salivary dysfunction, and associated cervical and approximal 

caries. B. Areas of caries and defective resin composite have been removed. The intense white appearance of the margins is typical of laser etching. 

C. The restored teeth immediately post-operatively. The etched appearance of the margins disappears once bonding resin has been placed. 

D. 30-year-old female patient with areas of hypoplastic enamel. E. The enamel surface has been ‘peeled’ using a series of pulses from the laser. 

F. The two areas have been restored with resin composite. G. 65-year-old female patient undergoing anti-cancer chemotherapy, with recurrent 

caries at the margins of several restorations. H. Areas of caries and undermined resin composite have been removed. I. The cavity preparations 

have been restored. 

for the efficient absorption of many commonly used 

dental lasers. 72 Certain procedures in patients with 

bleeding disorders are better suited to lasers with 

greater haemostatic capabilities (Table 9). Examples of 

simple soft tissue procedures are presented in Fig 5. 

CONCLUSIONS 

Laser technology for caries detection, resin curing, 

cavity preparation and soft tissue surgery is at a high 

state of refinement, having had several decades of 

development up to the present time. This is not to say 

that further major improvements cannot occur. Indeed, 

as is in the case with laser abrasion, the fusion of 

concepts from differing technologies may open the 

door to novel techniques and treatments. The field of 

laser-based photochemical reactions holds great 

promise for additional applications, particularly for 

targeting specific cells, pathogens or molecules. A 

further area of future growth is expected to be the 

combination of diagnostic and therapeutic laser 

techniques in the one device, for example the detection 

and removal of dental caries or dental calculus. For 


Table 7. Periodontal laser procedures 

Er:YAG 

2940nm 

Er,Cr:YSGG 

2780nm 

KTP 

532nm 

Argon 488 

and 515nm 

Diode 

810-980nm 

Nd:YAG 

1064nm 

Helium-neon 

633nm 

Diode 635, 

670 or 830nm 

CO2 10600nm 

Calculus removal 

Periodontal pocket 

✔ 

disinfection 

Photoactivated dye 

disinfection of 

✔ ✔ ✔ ✔ ✔ ✔ 

pockets 

De-epithelialization to 

✔ ✔ 

assist regeneration ✔ ✔ ✔ 

Table 8. Endodontic laser procedures 

CO2 Erbium:YAG Er,Cr:YSGG KTP Argon 488 Diode Nd:YAG Helium-neon Diode 635, 

10600nm 2940nm 2780nm 532nm and 515nm 810-980nm 1064nm 633nm 670, or 830nm 

Direct pulp capping 

Drying of the 

✔ ✔ 

root canal 

Removal of 

✔ ✔ ✔ 

smear layer 

Root canal 

✔ ✔ 

disinfection 

Photoactivated dye 

✔ ✔ ✔ ✔ ✔ ✔ 

disinfection of pockets ✔ ✔ 

example, an ‘autopilot’ system for subgingival 

débridement has been developed (for detailed review, 

see ref 73), and the potential exists to extend this 

concept further. 

There is a large research effort internationally 

focused on developing new laser applications for dental 

practice, and each year several large meetings are held 

which bring together this research. Examples include 

the International Society for Lasers in Dentistry (ISLD), 

the European Society for Oral Laser Applications 

(ESOLA), and the Academy of Laser Dentistry (ALD). 

With the further development of laser dentistry as an 

area of clinical pursuit, there will be considerable 

opportunity for clinicians to become involved in these 

research meetings and in specific research projects. The 

Australasian region has played a substantial role in the 

development of hard tissue laser applications, 74,75 and 

this level of involvement is expected to continue in the 

future, as various research groups examine uses for 

lasers in conjunction with or as a replacement for 

traditional methods. 

There is little argument that over recent years the use 

of lasers in dentistry in Australia has moved beyond 

Table 9. Surgical laser applications 

academic centres and specialist units into the 

mainstream of general practice. Looking to the future, 

it is expected that specific laser technologies will 

become an essential component of contemporary dental 

practice over the next decade. 

ACKNOWLEDGMENTS 

I thank the dental practitioners who have referred 

patients to the Laser Clinic over the past 12 years, and 

the numerous staff and students who have contributed 

to the dental laser research programme at the 

University of Queensland. 

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Er:YAG 2940nm 

(least haemostasis) 

Er,Cr:YSGG 

2780nm 

CO2 10600nm 

KTP 

532nm 

Diode 

810-980nm 

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and 515nm 

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✔ ✔ ✔ ✔ ✔ ✔ 

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of large 

✔ 

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Implant exposure 

✔ ✔ 

with bone removal ✔ ✔ ✔ 


Fig 5. Soft tissue procedures using middle and far infrared lasers. A. Pre-operative clinical appearance of a 22-year-old female with marked gingival 

overgrowth from nifedipine and cyclosporin. The patient has received a kidney transplant, is immuno-suppressed, and has a bleeding tendency. 

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Address for correspondence/reprints: 

Professor Laurence J Walsh 

School of Dentistry 

The University of Queensland 

200 Turbot Street 

Brisbane, Queensland 4000 

Email: l.walsh@uq.edu.au

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