LITHIUM DISILICATE CERAMICS SURFACE PRE-TREATMENT USING LOW-LEVEL LASER THERAPY-ACTIVATED RIBOFLAVIN, AND Ti: Al₂O₃ LASER ON THE COLOUR CHANGE, SURFACE ROUGHNESS, AND SHEAR BOND STRENGTH TO ADHESIVE CEMENT: AN IN VITRO SEM VALUATION

The present study aimed to examine the effectiveness of surface conditioners sandblasting (SB), Titanium Sapphire (Ti-Sapphire) laser, a low-level laser therapy activated riboflavin photosensitiser (LLLT-RFP) on the colour change (E), surface roughness (Ra) and shear bond strength (SBS) of Lithium Disilicate Ceramic LDC.Eighty LDC discs were prepared and categorised into four different groups based on the pre-treatment.(n = 20) Group 1: HF acid (S), Group 2: SB, Group 3: Ti-sapphire laser Group 4: LLLT activated RFP.Five samples from each group underwent a E assessment using a spectrophotometer.Surface Ra analysis was conducted on five specimens from each group using a profilometer.The bonding of a luting cement to the LDC discs was performed followed by the thermocycling of the specimens.An SBS and failure mode analysis were then performed using a universal testing machine and stereomicroscope, respectively.An analysis of variance was conducted to determine the mean and standard deviation (SD) of the E, Ra, and SBS.Tukey's post hoc multiple comparison test was used for the intergroup comparisons while maintaining a margin of error of 0.05.The highest outcomes of E were witnessed in the Group 1 specimens (HFA(S) + LDC).The minimum score of E was displayed by the Group 4 (LLLT activated RFP) + LDC) specimens.The highest scores of Ra and SBS were detected in Group 3 (Ti: Al 2 O 3 laser + LDC).Whereas Group 4 (LLLT activated RFP) + LDC exhibited the lowest Ra scores and bond integrity.The Ti-Sapphire laser proved to be a suitable alternative as it positively influences the mechanical properties (Ra, SBS) of the LDC.However, LDC conditioned with the Ti-Sapphire results in a considerable colour change which limits its application to posterior teeth only.