Applications Of Lasers In Dentistry: A Assessment

Applications of Lasers in Dentistry: A Assessment


Prof (Dr.) Bashir A Mir


Dept. of Oral and Maxillofacial Surgical procedures,

Govt. Dental University, Sgr.

Co authors:

Dr. Ajaz A Shah

Affiliate Professor and Head,

Dept. of Oral and Maxillofacial Surgical procedures,

Govt. Dental University, Sgr.

Dr. Suhail Latoo


Department of Oral Pathology and Microbiology,

Govt. Dental University, Sgr

Dr. Altaf H Malik

Dept. of Oral and Maxillofacial Surgical procedures,

Govt. Dental University, Sgr


 Lasers ended up launched into the field of scientific dentistry with the hope of overcoming some of the disadvantages posed by the traditional solutions of dental techniques. Because its 1st experiment for dental software in the nineteen sixties, the use of laser has amplified speedily in the past pair of decades. At current, wide types of techniques are carried out working with lasers. The intention of this overview is to explain the software of lasers in dental difficult tissue techniques. Lasers are observed to be productive in cavity preparing, caries removal, restoration removal, etching, and procedure of dentinal sensitivity, caries prevention and bleaching. Dependent on progress in adhesive dentistry and the propagation of least intervention concepts, lasers may revolutionize cavity style and design and preparing. 

 Important phrases: laser, dental difficult tissue, adhesive dentistry


The use of lasers in dentistry has amplified about the earlier several many years. The 1st laser was launched into the fields of medicine and dentistry through the nineteen sixties (Goldman et al., 1964). Because then, this science has progressed speedily. Because of their a lot of benefits, lasers are indicated for a wide range of techniques (Frentzen and Koort, 1990 Aoki et al., 1994 Pelagalli et al., 1997 Walsh, 2003). Common solutions of cavity preparing with low- and higher-pace handpieces include sounds, awkward vibrations and tension for people. Despite the fact that ache may be decreased by neighborhood anaesthesia, anxiety of the needle and of sounds and vibration of mechanical preparing stays causes of discomfort. These shortcomings have led to a search for new strategies as probable alternatives for dental difficult tissue removal. The intention of this overview is to explain the software of lasers in dental difficult tissue techniques. 

Historical progress

The 1st experiment with lasers in dentistry was noted in a study about the effects of a pulsed ruby laser on human caries (Goldman et al, 1964). The outcomes of that study showed that the effects varied from tiny two-mm deep holes to complete disappearance of the carious tissue, with some whitening of the surrounding rim of enamel, indicating extensive destruction of carious spots together with crater development and melting of dentine. Even more operate in the 1970’s focused on the effects of neodymium (Nd) and carbon dioxide (CO2) lasers on dental difficult tissues. Early researches observed that CO2 lasers generated cracking and disruption of enamel rods, incineration of dentinal tubule contents, too much reduction of tooth structure, carbonisation and fissuring and amplified mineralization triggered by the removal of organic and natural contents (Gimbel, 2000). It was also noted that the use of the CO2 laser was unfavourable since of the reduction of the odontoblastic layer (Wigdor et al., 1993).

Consequently, it was concluded that, except if heat-connected structural alterations and problems to dentinal tissues could be decreased, laser technological innovation could not replace the traditional dental drill. Even more advancements in laser technological innovation on the other hand, have determined appropriate biologic interactions. For instance, the Er: YAG laser was analyzed for its means to ablate (or vapourise) dental difficult tissues (Gimbel, 2000). Enamel and dentine cavities ended up properly geared up working with the Er: YAG laser. Because then, this laser has been made use of for caries removal and cavity preparing, tender tissue small surgical treatment and scaling (Aoki and Watanabe et al., 1998).

Scientific Applications

Cavity preparing

The Er: YAG laser was analyzed for getting ready dental difficult tissues for the 1st time in 1988. It was properly made use of to get ready holes in enamel and dentine with low ‘fluences’ (electricity (mJ)/device place (cm2)). Even without the need of h2o-cooling (Burkes et al., 1992), the geared up cavities showed no cracks and low or no charring although the mean temperature rise of the pulp cavity was about four.3°C (Rechmann et al., 1998). In 1989, it was demonstrated that the Er: YAG laser generated cavities in enamel and dentine without the need of important adverse facet effects. The ablation performance was about one purchase of magnitude lessen than for tender tissue. It was then concluded that dentine and enamel removal was incredibly productive with no possibility to the pulp (Armengol, 2000 Cavalcanti, 2003) and the ablation rates in enamel ended up mentioned to be in the variety of twenty-50 µm/pulse, and in dentine they ended up noted to be as higher at lessen fluences.

Clinically, cavity preparing in enamel outcomes in ablation craters with a white chalky overall look on the surface of the crater (Tokonabe et al., 1999). In dentine, cavity margins are sharp and dentinal tubules keep on being open up without the need of a smear layer. In a scientific study carried out to consider the performance and basic safety of the Er: YAG laser for caries removal and cavity preparing in dentine and enamel (Cozean et al, 1997), Course I, II, III, IV and V cavities ended up geared up for amalgam and composite restorations. It was observed that the Er: YAG laser was equal to the air rotor in its means to make cavity preparations in enamel and dentine and eliminate caries. On the other hand, the flooring of the preparing was not as smooth as that reached with the higher-pace drill.  

Caries removal

Carious substance is made up of a higher h2o articles in comparison with surrounding healthier dental difficult tissues. For that reason, the ablation performance of caries is bigger than for healthier tissues. There is a achievable selectivity in the removal of carious substance working with the Er: YAG laser since of the different electricity requirement to ablate carious and audio tissues leaving those healthier tissues minimally affected. On the other hand, Rechmann et al. (1998) observed that selective ablation of carious dentine is tricky with the Er: YAG laser. The ablation thresholds of healthier dentine and carious dentine are different. The ablation threshold of healthier dentine is two times higher than the corresponding threshold of carious dentine.

Consequently, incredibly tiny fluences (electricity (Joules) / place (cm2)) of the Er: YAG laser electricity are demanded to selectively ablate carious dentine. This low fluence will final result in low performance of the ablation system (Shigetani, 2002). In another in vitro study investigating the success of caries removal by Er: YAG laser, it was observed that the Er: YAG laser ablated carious dentine successfully with minimum thermal problems to the surrounding intact dentine (Aoki and Ishikawa et al., 1998). The laser eradicated infected and softened carious dentine to the identical diploma as the bur procedure. In addition, a lessen diploma of vibration was observed with the Er: YAG laser procedure. On the other hand, the study did not tackle the issue of selective removal of carious tissue and further experiments of caries removal working with lasers are indicated. 

Restoration removal

The Er: YAG laser is capable of removing cement, composite resin and glass ionomer (Dostalova et al., 1998 Gimbel, 2000). The performance of ablation is comparable to that of enamel and dentine. Lasers must not be made use of to ablate amalgam restorations on the other hand, since of probable release of mercury vapour. The Er: YAG laser is incapable of removing gold crowns, forged restorations and ceramic elements since of the low absorption of these elements and reflection of the laser mild (Keller et al., 1998). These restrictions emphasize the require for sufficient operator teaching in the use of lasers.


Laser etching has been evaluated as an option to acid etching of enamel and dentine. The Er: YAG laser provides micro-explosions through difficult tissue ablation that final result in microscopic and macroscopic irregularities. These micro-irregularities make the enamel surface micro-retentive and may give a mechanism of adhesion without the need of acid-etching. On the other hand, it has been demonstrated that adhesion to dental difficult tissues right after Er: YAG laser etching is inferior to that attained right after traditional acid etching (Martinez-Insua et al., 2000). These authors attributed the weaker bond toughness of the composite to laser-etched enamel and dentine to the existence of subsurface fissuring right after laser radiation. This fissuring is not found in traditional etched surfaces. The subsurface fissuring contributed to the higher prevalence of cohesive tooth fractures in bonding of equally laser-etched enamel and dentine.

A comparable conclusion was drawn from a study that in comparison shear bond toughness (SBS) of composite resin to dentine surfaces subsequent different treatment options (Ceballos et al., 2001). These authors noted that acid etched specimens reached the optimum SBS values, although laser procedure showed the cheapest SBS outcomes. These conclusions suggest that extensive fissuring triggered by laser procedure and the consequent lousy bonding toughness may outweigh the putative benefits of laser etching.

Treatment method of dentinal hypersensitivity

Dentinal hypersensitivity is one of the most frequent grievances in dental scientific follow. Various procedure modalities these kinds of as the software of concentrated fluoride to seal the exposed dentinal tubules have been analyzed to treat the ailment. On the other hand, the achievements level can be drastically enhanced by the ongoing analysis of lasers in difficult tissue programs. A comparison of the desensitising effects of an Er: YAG laser with those of a traditional desensitising procedure on cervically exposed hypersensitive dentine (Schwarz et al., 2002) showed that desensitising of hypersensitive dentine with an Er: YAG laser is productive, and the routine maintenance of a beneficial final result is extra extended than with other agents.

Caries prevention

Various experiments examined the possibility of working with laser to stop caries (Hossain et al., 2000 Apel et al., 2003). It is believed that laser irradiation of dental difficult tissues modifies the calcium to phosphate ratio, decreases the carbonate to phosphorous ratio, and qualified prospects to the development of extra steady and significantly less acid soluble compounds, lessening susceptibility to acid assault and caries. Laboratory experiments have indicated that enamel surfaces exposed to laser irradiation are extra acid resistant than non-laser addressed surfaces (Watanabe et al., 2001 Arimoto et al., 2001).

The diploma of security from caries development presented by the one-time original laser procedure was noted to be comparable to everyday fluoride procedure by a fluoride dentifrice (Featherstone, 2000). The threshold pH for enamel dissolution was reportedly lowered from 5.5 to four.eight and the difficult tooth structure was 4 times extra resistance to acid dissolution. On the other hand, the genuine mechanism of acid resistance by laser irradiation is however unclear and experiments, notably in vivo, to exam those claims are demanded.


The aim of laser bleaching is to achieve an productive energy bleaching system working with the most efficient electricity source, although staying away from any adverse effects (Sunshine, 2000). Electric power bleaching has its origin in the use of higher-depth mild to increase the temperature of hydrogen peroxide, accelerating the chemical system of bleaching. The Food and drug administration permitted criteria for tooth whitening has cleared a few dental laser wavelengths: argon, CO2 and the most latest 980-nm GaAIAs diode. There are no studies at current about the use of the Er: YAG laser in bleaching strategies. The wavelength of the Er: YAG laser may be unsuitable for the techniques, but it is a further place that could be explored.


The Er: YAG laser has been observed to have programs in spots these kinds of as cavity preparing, removal of caries and restorations, and etching of enamel. On the other hand, the benefits as very well as restrictions of the Er: YAG laser treatment options have not yet been completely documented. There show up to be windows of chance for the Er: YAG laser in a variety of dental programs. Lasers may revolutionise cavity style and design and preparing primarily based on progress in adhesive dentistry. 


Aoki A, Ando Y, Watanabe H and Ishikawa I (1994). In vitro experiments on laser scaling of sub-gingival calculus with an erbium: YAG laser. J Periodontal, 65: 1097 – 1106

Aoki A, Ishikawa I, Yamada T, Otsuki M, Watanabe H, Tagami J, Ando Y and Yamamoto H (1998). Comparison concerning Er: YAG laser and traditional technique for root caries procedure in nitro. J Dent Res, six: 1404-1414.

Aoki A, Watanabe H and Ishikawa I (1998). Er: YAG scientific working experience in Japan: overview of scientific investigations. SPIE, 3248: forty-forty five.

Apel C, Schafer C and Gutknecht N (2003). Demineralization of Er: YAG and Er,Cr: YSGG Laser-Geared up Enamel Cavities in vitro. Caries Res, 37: 34-37.

Arimoto N, Suzaki A, Katada H and Senda A (2001). Acid Resistance in Lased Dentine. 6th International Congress on Lasers in Dentistry, sixty one-sixty two.

Armengol V, Jean A and Marion D (2000). Temperature rise through Er: YAG and Nd: YAP laser ablation of dentine. J Endodon, 26(3): 138 –


Burkes EJ, Hoke J, Gomes E and Wolbarsht M (1992). Moist vs . dry enamel ablation by Er: YAG laser. J Prosthet Dent, 67: 847-851.

Cavalcanti BN, Lage-Marques JL and Rode SM (2003). Pulpal temperature will increase with Er: YAG laser and higher-pace handpieces. J Prosthet Dent, ninety: 447-451.

Ceballos L, Osorio R, Toledano M and Marshall GW (2001). Microleakage of composite restorations right after acid or Er: YAG laser cavity procedure. Dental Supplies, 17: 340-346.

Cozean C, Arcoria CJ, Pelagalli J and Powell GL (1997). Dentistry for the 21st century? Erbium: YAG laser for tooth. J Am Dent Assoc, 128: 10801087.

Dostalova T, Jelinkova H, Kucerova H, Krejsa O, Hamal K, Kubelka J and Prochazka S (1998). Noncontact Er: YAG Laser Ablation: Scientific Evaluation. J Clin Laser Med Surg, sixteen(5): 273

Featherstone JDB (2000). Caries detection and prevention with laser electricity. Dental Clinics of North The us, 44(four): 955-969.

Frentzen M and Koort HJ (1990). Lasers in dentistry: new possibilities with advancing laser technological innovation? Int Dent J, forty: 323 – 332

Gimbel CB (2000). Tricky tissue laser techniques. Dental Clinics of North The us, 44(four): 931-953.

Goldman L, Hornby P, Meyer R and Goldman B (1964). Impact of the laser on dental caries. Mother nature, 203: 417.

Hossain M, Nakamura Y, Kimura Y, Yamada Y, Ito M and Matsumoto K (2000). Caries-Preventive Effect of Er: YAG Laser Irradiation with or without the need of Drinking water Mist. J Clin Laser Med Surg, 18(two): sixty one-65.

Keller U, Hibst R, Geurtsen W, Schilke R, Heidemann D, Klaiber B and Raab WHM (1998). Erbium: YAG laser software in caries remedy. Evaluation of patient perception and acceptance. J Dent, 26: 649-656.

Martinez-Insua            A, Dominguez LS, Rivera FG and Santana-Penin UA (2000). Dissimilarities in bonding to acid-etched or Er: YAG – laser – addressed enamel and dentine surfaces. J Prosthet Dent, 84: 280-288.

Pelagalli J, Gimbel CB, Hansen RT, Swett A and Winn II DW (1997). Investigational Review of the Use of Er: YAG Laser As opposed to Dental Drill for Caries Elimination and Cavity Planning – Stage I. J Clin Laser Med Surg, 15(3): 109 – a hundred and fifteen.

Rechmann P, Goldin DS and Hennig T (1998). Er: YAG lasers in dentistry: an overview. SPIE, 3248: 0277-0286.

Schwarz F, Arweiler N, Georg T and Reich E (2002). Desensitising effects of an Er: YAG laser on hypersensitive dentine, a managed, prospective scientific study. J Clin Periodontol, 29: 211-215.

Shigetani Y, Okamoto A, Abu-Bakr N and Iwaku M (2002. A study of cavity preparing by Er: YAG laser – observation of difficult tooth structure by laser scanning microscope and evaluation of the time important to eliminate caries. Dent Mater J, 21(one): twenty – 31.

Sunshine G (2000). The position of lasers in cosmetic dentistry. Dental Clinics of North The us, 44(four): 831-850.

Tokonabe H, Kouji R, Watanabe H, Nakamura Y and Matsumoto K (1999). Morphological alterations of human tooth with Er: YAG laser irradiation. J Clin Laser Med Surg, 17(one): seven-12.

Watanabe H, Yamamoto H, Kawamura M, Okagamv Y, Kataoka K and Ishikawa I (2001). Acid Resistance of the Human Tooth Enamel Irradiated by Er: YAG Laser. 6th International Congress on Lasers in Dentistry, sixty eight-sixty nine.

Walsh LJ (2003). The present-day standing of laser programs in dentistry. Aust Dent J, 48(3): 146

Wigdor H, Abt E, Ashrafi S and Walsh Jr JT (1993). The impact of lasers on dental difficult tissues. J Am Dent Assoc, 124: 65-70. 

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