Effect of Diode Laser (۸۱۰ nm) Irradiation on Marginal Microleakage of Multi-mode Adhesive Resins in Class V Composite Restorations

Abstract Introduction: Some studies have shown that laser irradiation on unpolymerized adhesives can improve composite-dentin adhesion. The aim of the present study was to evaluate the effect of the Diode laser (۸۱۰ nm) on the microleakage of multi-mode adhesive systems at enamel and dentin margins of composite restorations.Methods: Classic Class V boxes were prepared on ۴۸ sound premolar teeth and randomly divided into six groups (n=۱۶). In the control groups, Scotch bond U(SBC), G-Premio (GBC), and Ambar U (AMC) were used by a self-etch mode. In the test groups (SBL, GBL, ABL), the ۸۱۰ nm Diode laser was irradiated (۱ Watt) for ۱۰ seconds before the polymerization of the adhesive. The Boxes were restored by the resin composite. After finishing and polishing, the samples were thermocycled (۵℃ to۵۵℃) for ۱۰۰۰ cycles and then immersed in ۰.۱% Methylene blue dye (۴۸ hours). Dye penetration through the gingival and occlusal margins was measured by Stereomicroscope. The data were analyzed at the ۵% significance level using Kruskal-Wallis and Mann-Whitney U tests.Results: Significant differences were found between the control and test groups (p<۰.۰۵). The occlusal margins of the SBL and GBL groups and the cervical margin of the SBL group exhibited the lowest microleakage (p<۰.۰۵). The AM control group showed maximum microleakage at cervical and occlusal margins.Conclusions: The irradiation of the ۸۱۰ nm Diode laser on the unpolymerized universal adhesive systems in a self-etch mode caused a significant reduction in enamel and dentin marginal microleakage of composite restorations. Keywords: Adhesive Lasers Dental leakage dentin bonding agent Diode Lasers