Effect of Er,Cr:YSGG Laser Versus Acid Etching Surface Treatment on the Surface Roughness and Topography of Two Pressable Lithium Disilicate Ceramics. “In-Vitro Study”.

Abstract

Objective: To assess the effect of two surface treatment protocols of two pressable lithium disilicate ceramics with different thicknesses on the surface roughness and topography. Material and methods: Sixty four lithium disilicate ceramic discs were divided into two groups (n=32); IPS e.max Press and InitialTM LiSi Press. Each group was subdivided into two subgroups (n=16) according to thicknesses (0.5mm and 1mm). Each subgroup was divided into two subdivisions (n=8) according to the surface treatment; Er:Cr:YSGG Laser and hydrofluoric acid etching. Artificial aging was performed for all the specimens. Surface roughness (Ra) before and after surface treatment protocol was measured using contact stylus profilometer and their topographical changes were identified using scanning electron microscope. Results: there was no significant difference in Ra values between the two ceramic types before and after surface treatment. There was no significant difference in Ra values between the two surface treatments on both ceramics. There was a difference in the effect of the surface treatments on the topography of the ceramics Conclusion: Both surface treatments have comparable effect on the surface roughness of lithium disilicate ceramic but have different effect on the ceramic’s topography.