Microshear Bond Strength of a Self-adhesive Composite to Erbium Laser-Treated Primary Enamel

Abstract Introduction: Advances have been made in the composition of flowable composites in recent years and self-adhering composites, which do not require a bonding agent, have recently been introduced to the market. This study aimed to assess the microshear bond strength (μSBS) of a self-adhering flowable composite (Vertise) to primary enamel treated with a graphite disc with silicon carbide particles (SIC) and laser irradiation, the result of which was compared to that of a conventional flowable composite (Premise).Methods: In this in vitro, experimental study, ۷۲ samples of sound primary enamel were evaluated. A smooth enamel surface was obtained using a graphite disc. Next, the erbium chromium yttrium scandium gallium garnet (Er,Cr:YSGG) laser was used for enamel surface treatment in half of the samples (n = ۳۶). All the samples were then randomly divided into ۴ groups of (i) Premise flowable composite (PF) without laser (n = ۱۸), (ii) Vertise flowable composite (VF) without laser (n = ۱۸), (iii) PF with laser (n = ۱۸), and (iv) VF with laser (n = ۱۸). The teeth were then incubated at ۳۷°C for ۲۴ hours and were then subjected to thermocycling. The μSBS of samples was measured using a universal testing machine and reported in megapascal (MPa). Data were analyzed using SPSS via the two-way ANOVA and independent-samples t test at P < ۰.۰۵.Results: The mean μSBS of VF was significantly higher to the laser-treated samples (۱۳.۶۰ ± ۵.۴۷) compared with the non-treated samples (۵.۸۹ ± ۲.۴۲) (P < ۰.۰۰۱). However, no significant difference was noted in the μSBS of PF to the laser-treated (۱۳.۱۸ ± ۳.۴۵) and non-treated samples (۱۶.۰۶ ± ۳.۵۲) (P = ۰.۰۵۸).Conclusion: The μSBS of the conventional flowable composite is higher than that of the self-adhering flowable composite to the enamel of primary teeth. Enamel surface treatment with laser irradiation increases the μSBS of self-adhering flowable composites. Keywords: Microshear Bond Strength Self-adhering Flowable Composite Laser Primary Enamel