Laser Application in Operative Dentistry

What is the wavelength range of soft-tissue lasers within the visible light spectrum?

488 nm, 515 nm, to 535 nm

What are the wavelengths of near-infrared soft-tissue lasers?

810 nm, 940 nm, 980 nm, and 1064 nm

What type of laser light was originally used in laser fluorescence systems for detection of dental caries?

Visible blue light from the argon laser

What is the advantage of laser fluorescence in detecting dental caries in pits and fissures?

Greater sensitivity than conventional visual and tactile methods Signup and view all the answers

What type of laser is used to elicit fluorescence from bacterial deposits in carious lesions?

Visible red laser light from a semiconductor diode laser Signup and view all the answers

In what setting is argon laser-induced fluorescence particularly valuable?

Detection of proximal lesions Signup and view all the answers

What is a potential application of using the carbon dioxide laser in early fissure caries?

To reveal such lesions and modify the fissure system to increase resistance to future carious attack. Signup and view all the answers

What was the outcome of using the Er: YAG laser to prepare holes in enamel and dentine without water-cooling?

The prepared cavities showed no cracks and low or no charring. Signup and view all the answers

What is the benefit of using dyes in conjunction with laser fluorescence in approximal surfaces?

To delineate cavitated from non-cavitated lesions in sites of poor clinical access. Signup and view all the answers

What is the appearance of ablation craters on the surface of enamel after cavity preparation with the Er: YAG laser?

A white chalky appearance. Signup and view all the answers

What is the difference in the cavity margins of dentine after cavity preparation with the Er: YAG laser?

The margins are sharp and dentinal tubules remain open without a smear layer. Signup and view all the answers

Why is the Er: YAG laser effective in removing carious material?

Because carious material contains a higher water content compared with surrounding healthy dental hard tissues. Signup and view all the answers

What is the primary advantage of using the Er: YAG laser for caries removal?

The ability to selectively remove carious material while leaving healthy tissues minimally affected. Signup and view all the answers

How does the ablation threshold of healthy dentine compare to that of carious dentine?

The ablation threshold of healthy dentine is two times higher than that of carious dentine. Signup and view all the answers

What is the effect of the Er: YAG laser on gold crowns, cast restorations, and ceramic materials?

The Er: YAG laser is incapable of removing these materials due to their low absorption and reflection of the laser light. Signup and view all the answers

What is the significance of the micro-explosions produced during hard tissue ablation by the Er: YAG laser?

They result in microscopic and macroscopic irregularities, similar to etching. Signup and view all the answers

Why should the Er: YAG laser not be used to ablate amalgam restorations?

Due to the potential release of mercury vapor. Signup and view all the answers

How does the vibration associated with the Er: YAG laser treatment compare to that of bur treatment?

A lower degree of vibration is noted with the Er: YAG laser treatment. Signup and view all the answers

What is the potential advantage of microirregularities on the enamel surface in terms of adhesion?

They can provide a mechanism of adhesion without acid-etching Signup and view all the answers

Why is adhesion to dental hard tissues after Er: YAG laser etching inferior to that obtained after conventional acid etching?

Due to the presence of subsurface fissuring after laser radiation Signup and view all the answers

What is the effect of argon laser radiation on the surface chemistry of enamel and root surface dentine?

It reduces the probability of recurrent caries Signup and view all the answers

What is the advantage of argon laser curing compared to conventional quartz tungsten halogen lamp units in terms of temperature increase?

The temperature increase at the level of the dental pulp is much less with argon laser curing Signup and view all the answers

What is the role of camphoroquinone in light-cured dental restorative materials?

It acts as the photoinitiator Signup and view all the answers

What is the common dental complaint that can be treated with lasers?

Dentinal hypersensitivity Signup and view all the answers

What is the primary goal of laser bleaching in dentistry?

To achieve an effective power bleaching process using the most efficient energy source, while avoiding any adverse effects. Signup and view all the answers

How does laser irradiation of dental hard tissues affect their susceptibility to acid attack and caries?

It modifies the calcium to phosphate ratio, reduces the carbonate to phosphorous ratio, and leads to the formation of more stable and less acid soluble compounds. Signup and view all the answers

What is the advantage of using an Er: YAG laser in treating hypersensitive dentine compared to conventional desensitizing systems?

The maintenance of a positive result is more prolonged than with other agents. Signup and view all the answers

What is the potential application of lasers in preventing caries?

Modifying the calcium to phosphate ratio and reducing the carbonate to phosphorous ratio, making dental hard tissues less susceptible to acid attack and caries. Signup and view all the answers

What is the effect of laser irradiation on the acid resistance of enamel surfaces?

It makes them more acid resistant. Signup and view all the answers

Why is the ongoing evaluation of lasers in hard tissue applications important in treating dentinal hypersensitivity?

It can greatly improve the success rate of treatment. Signup and view all the answers