Effect of Er Cr YSGG laser etching procedure on the bond strength of different calcium silicate cements

Purpose: The study aimed to evaluate the efficacy of self-etch, acid-etch, and laser-etch techniques on the bond strength between various calcium silicate cements (CSC) and resin composite. Methods: 120 specimens of MTA, Biodentine, Theracal LC, and Theracal PT were produced according to manufacturers’ instructions. The disks were divided into 3 subgroups: control (self-etch), acid etch, and laser etch (70.74 J/cm²; average power 4 W, 20 Hz, 75% H₂O, and 65% air(n = 10). The samples underwend microshear bond strength tests and the types of fractures were examined. Surface topography and micromorphology were assessed using SEM and AFM. Data were analyzed using two-way ANOVA and Sidak. Results: Theracal PT exhibited the highest bond strength among the calcium silicate materials, followed by Theracal LC, Biodentine, and MTA. The no acid-no laser etchcontrol group showed significantly lower bond strength compared to the acid etch and laser etch groups (p < 0.001), with no difference between the acid etch and laser etch groups (p > 0.05). Conclusion: Through SEM and AFM analysis, the surface morphological changes induced by acid and laser etching on the materials were observed. The findings demonstrate that surface treatment through acid and laser etching can significantly enhance the bond strength of CSCs to resin composites. For effective adhesion, acid or laser etching application may be advisable.