The Journal of Oral Laser Applications
J Oral Laser Applications 8 (2008), No. 2     4. July 2008
J Oral Laser Applications 8 (2008), No. 2  (04.07.2008)

Page 103-107

Morphological Changes in Dental Hard Tissues Using Diamond Rotary Instruments and Er,Cr:YSGG Laser: A Comparative Study
Merchant, Natasha / Hegde, Vivek / Thukral, Naresh
Purpose: This in vitro study was designed to morphologically analyze, using ESEM, any differences in the microscopic surface of Class V cavities using rotary diamond abrasive instruments and Er,Cr:YSGG laser.
Materials and Methods: Twenty extracted human premolars were used. The teeth were brushed and cleaned under tap water and stored in distilled water at room temperature. The teeth were divided into two groups containing 10 teeth each. Standardized Class V cavities were prepared on the buccal surface of all teeth. Cavities in group 1 teeth were prepared using a high-speed air turbine handpiece. Cavities in group 2 teeth were prepared using an Er,Cr:YSGG laser (Waterlase). The laser emits a wavelength of 2790 nm with a pulse frequency of 20 Hz. The delivery tip was held at a distance of 1.5 mm from the target tissues and used in a back and forth motion.
Results: The margins of the cavities prepared by conventional diamond rotary instruments were sharp and more irregular. Smear layer and debris were seen covering the peripheral walls and the depth of the cavity in the rotary preparations. The walls of the cavity prepared by the laser were smooth and the dentinal tubules were not plugged. Ablation of hard tissues was observed in the laser preparations.
Conclusion: Dental lasers are highly efficient tools in cavity preparation. Not only are they completely safe, but they also provide better surface morphology, which has characteristic features for better retention of the restorative materials.

Keywords: dental lasers, hard tissues, Class V cavities, rotary abrasives, ESEM analysis, Er,Cr:YSGG laser