Purpose: To assess the effect of Er,Cr:YSGG pulsed laser surface treatment versus hydrofluoric acid etching on microtensile bond strength ( µTBS) to three different types of CAD/CAM ceramic materials cemented with two self-adhesive resin cements.
Materials and Methods: Ceramic slices (n=24) were prepared from three different types of CAD/CAM blocks: Vita Enamic (group: VE), IPS e.max CAD (group: EM) and Obsidian (group: OB). Two surface treatments were applied followed by silane primer: Er,Cr:YSGG laser (Subgroup ER) and hydrofluoric acid (Subgroup HF as a control). ESEM evaluation was performed before and after surface treatments, accompanied with measurement of roughness (Ra). Two self-adhesive resin cements were used: BisCem (Division BC) & Panavia SA Cement plus (Division PA). After 24 hours storage in distilled water, the ceramic-resin blocks were sectioned into micobeams. A total of 480 microbeams were subjected to (µTBS) testing. Data was tabulated and statistically analyzed.
Results: ESEM revealed variations in surface texture. Regarding VE group, HF recorded statistically higher significant µTBS with PA. While, EM group, HF showed statistically higher significant µTBS for both cements compared to ER. OB group HF showed statistically higher significant µTBS with PA in contrast to ER which showed statistically higher significant µTBS with BC.
Conclusions: The interaction of Er,Cr:YSGG pulsed laser with the surfaces of the tested CAD/CAM materials seemed to be different and dependent on the crystalline structure of these ceramics. Variation of the chemical formulae of self-adhesive resin cements played a great role in determining the µTBS to the tested CAD/CAM materials.