The Effect of different power settings of Er,Cr:YSGG Laser on Tooth Structure Chemistry and Topography and time of Debonding of Laminate Veneers : "In Vitro Study"

Abstract

Introduction: Laminate veneers are an ultraconservative restoration that need minimal preparation and are highly esthetic and biocompatible. The development of ceramics and resin cements increase the use of laminate veneers restoring esthetics and function. However, debonding of laminate veneers in one piece without destruction or touching underlying tooth structure is challenging. Laser introduction has afforded a great tool of help. Aim of the study: to evaluate the effect of Er,Cr:YSGG laser of different power settings on tooth structure chemistry and topography after debonding of laminate veneers. Materials and methods: Fifteen laminate veneers were prepared and bonded to maxillary central incisors, they were divided into three equal groups (n=5) according to laser power settings. Each group was subjected to its respective laser power (2, 4 and 6 Watt) to debond laminate veneers, time was recorded. Results: All laminate veneers were debonded with different laser power settings. Calcium and phosphorus both decreased from before bonding to after debonding. Surface roughness showed increase from before etching in respect to after etching, but surface roughness after etching and after debonding didn’t show a big difference. Debonding time decreased when the laser power setting increase. Roughness of fitting surface of laminate veneers showed almost same results comparing before bonding to after debonding. Mode of failure mainly was cohesive with different power settings. Conclusion: Laser is useful in laminate veneer debonding. It provides two main advantages that the tooth structure not affected and the laminate veneer remained intact with less time and easier technique for debonding.