Lasers: The Magic Wand in Esthetic Dentistry!!

In this era of fast developing technologies and innovative ideas, the need for faster treatment has become a necessity. Treatment with lasers that is much less time-consuming and painless is accepted and appreciated by the patient. Use of Lasers is not new; they have been in use for decades since their development by Maiman in 1960. Lasers have travelled a long way from ruby lasers to erbium lasers and are being fondly used in every aspect of dental treatment. This article aims at elaborate the use and applications of lasers in the field of esthetic dentistry.

Introduction

Lasers are the acronym for “light amplification by stimulated emission of radiation” named in 1957 by Gordon Gould. The first laser to be used was that introduced by Theodore Harold Maiman in 1960 was the Ruby laser.1 Lasers are now being used extensively as an adjunct to dental treatment to increase the prediction and precision of the treatment.

Laser Physics

Light is a form of electromagnetic energy that behaves as a particle wave. The basic unit of this energy is called as photon.2

Laser light has three main properties that differentiate it from normal light.3 They are:

Collimation: Refers to the beam having specific spatial boundaries which ensure that there is a constant beam size and shape that is emitted from the laser unit.

Coherence: A unique property of lasers that states that they have identical frequency and identical wavelength.

Monochromatism: The property of lasers that it possesses one specific color which is finely focused.

Laser tissue interaction

Absorption

The amount of energy that is absorbed by the tissue depends on the tissue characteristics, primarily water content, presence of pigments, laser wavelength and their emission modes. In general, shorter wavelengths are readily absorbed in pigmented tissue and blood elements.4

Transmission

The second effect is transmission of the laser energy directly through the tissue with no effect on the target tissue, inverse of absorption. This effect is also dependent on the wavelength of laser light.2

Reflection

The third effect is a reflection, which is the beam redirecting itself off the surface, having minimal or no effect on the target tissue.5

Scattering

The fourth effect is a scattering of the laser light which weakens the intended energy and possibly produces no useful biological effects instead scattering causes heat transfer to the tissue adjacent to the surgical site, and unwanted collateral damage could occur.6

The main effect of laser is due to the absorption of laser by various components of the tissue it is exposed to. The primary component that absorbs specific laser energy is termed as chromophores. The chromophore for various lasers differs (Table 1).

Table 1

Chromophores of various lasers.

Application of Lasers to Aid in Dentistry

The successful of prosthetic treatment mainly depends on the pre-operative evaluation of the supporting hard and soft tissue structures and their proper preparation.7

Fixed prosthodontics

Crown lengthening

Soft tissue management around abutments

Modification of soft tissue around laminates

Osseous crown lengthening

Troughing

Formation of ovate pontic sites (Figure 1)

Figure 1

Laser assisted ovate pontic site preparation.

Altered passive eruption management

Veneer removal

Dentinal hypersensitivity

Tooth preparation (Figure 2).

Figure 2

Effect of erbium laser on tooth enamel.

Implantology

Second stage uncovering

Implant site preparation

Peri-implantitis.

Removable prosthetics

Tuberosity reduction

Torus reduction

Soft tissue modification

Epulis fissurata

Denture stomatitis

Residual ridge modification.

Complete denture prosthodontics

Prototyping and computer aided design and computer aided manufacturing (CAD/CAM) technology.

Analysis of occlusion by CAD/CAM.

Analysis of accuracy of impression by the laser scanner.

Laser application in dental laboratory

Laser titanium sintering – direct metal laser sintering (Figure 3)

Figure 3

Metal crowns formed with direct metal laser sintering.

Laser ablation of titanium surfaces

Laser assisted hydroxyapatite coating

Laser welding of titanium components of the prostheses (Figure 4).

Figure 4

Laser welding.

Laser in maxillofacial prosthodontics

Planning the shape and position of the prostheses

Three-dimensional acquisition of optical data of the extra-oral defects - selective laser sintering technology.

Esthetic procedures

Laser bleaching

Laser depigmentation.

Orthodontic esthetic enhancement8

Laser etching

Laser debonding

Laser scanning

Laser holography

Laser spectacular reflectance.

The latest application of lasers includes low-level laser therapy. The biostimulatory effect of lasers is implied in low-level laser therapy.9 The various applications of low-level laser therapy are:

Dentinal hypersensitivity

Temporomandibular disorders

Treatment of pain during orthodontic tooth movement

Bone implants interphase for better healing.

Lasers are also used effectively in pediatric and apprehensive patient with much cooperation and helps in better treatment.10

Conclusion

Lasers have become a ray of hope in dentistry. When used ethically and effectively, lasers are an exceptional “magic wand” in the treatment for many clinical conditions that dentists treat on a daily basis. However, lasers have never been the “magic tool” that many people have hoped for. It has got its own limitations. The addition of laser to dental treatment enhances the dentist’s ability to perform more clinical procedures, increase confidence and experience.