Effects of Er:YAG and Er,Cr:YSGG laser irradiation and adhesive systems on microtensile bond strength of a self-adhering composite.

ABSTRACT

This study was aimed to evaluate the effects of ErYAG and Er,CrYSGG laser irradiation and adhesive systems on the microtensile bond strength of Fusio Liquid Dentin (FLD) which is a self-adhering composite (SAC). Twenty-four freshly extracted human molar teeth were collected, and the enamel was removed from the occlusal surface to obtain a flat dentin surface. Twenty-four teeth were randomly divided into eight groups Group 1 only Fusio Liquid Dentin (FLD) (Petron Clinical, Orange, California, USA) was applied to the dentin surface; Group 2 37% Phosphoricacid (i-GEL, Medicinos Linija UAB, Lithuania) + FLD; Group 3 Single Bond Universal (SBU) (3 M ESPE, Germany) + FLD; Group 4 Adper Easy One (AEO) (3 M ESPE, Germany) + FLD; Group 5 ErYAG laser + AEO + FLD; Group 6 ErYAG laser + SBU + FLD; Group 7 Er,CrYSGG laser + AEO + FLD; and Group 8 Er,CrYSGG laser + SBU + FLD. After thermocycling, 1 × 1 mm2 sticks were used for the µTBS test (n = 10). Two sticks per group were used for SEM analysis. Fractured sample surfaces were evaluated using a stereomicroscope. Group 8 showed the highest µTBS value (13.70 MPa), whereas Group 1 showed the lowest µTBS value (5.60 MPa). There were no significant differences between Groups 2, 3, and 4 (P = 0.324), but Groups 5-8 showed statistically significant results that were higher than Groups 1-4 (P = 0.012). Adhesive failure mode was predominant followed by mixed failure. The evaluation of bonding of the FLD to dentin showed that the combined use of ErYAG and Er,CrYSGG lasers with SBU and AEO on dentin surfaces improved the dentinal bond strength of the FLD.