Effect of Diode Laser (810 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 (810 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 48 sound premolar teeth and randomly divided into 6 groups (n=16). In the control groups, Scotchbond Universal (SBC), G-Premio (GBC), and Ambar U (AMC) were used by a self-etch mode. In the test groups (SBL, GBL, ABL), the 810 nm diode laser was irradiated (1 W) for 10 seconds before the polymerization of the adhesive. The boxes were restored by the resin composite. After finishing and polishing, the samples were thermocycled (5°C to 55°C) for 1000 cycles and then immersed in 0.1% methylene blue dye (48 hours). Dye penetration through the gingival and occlusal margins was measured by Stereomicroscope. The data were analyzed at the 5% significance level using Kruskal-Wallis and Mann-Whitney U tests. Results: Significant differences were found between the control and test groups (P<0.05). The occlusal margins of the SBL and GBL groups and the cervical margin of the SBL group exhibited the lowest microleakage (P<0.05). The AM control group showed maximum microleakage at cervical and occlusal margins. Conclusion: The irradiation of the 810 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.

Comparative evaluation on the effect of different cavity disinfectant nano gels; Chlorohexidine, Propolis, Liquorice versus Diode Laser in terms of composite microleakage

“…Unfortunately, there was a shortage of studies evaluating the effect of Diode laser as a cavity disinfectant on the degree of microleakage at tooth-restoration interface while limited studies evaluated its effect on the bond strength or its antibacterial potentiality. 10,31,34 In accordance with our results, Golbari et al 2019 39 concluded that 810 nm Diode Laser could reduce marginal microleakage at the tooth-restorations interface. However, Ipek et al 2020 6 proved that the Diode laser didn't show any favorable effect on the drgree of microleakage at tooth -restoration interface.…”

Effect of 9.3 μm CO2 and 2.94 μm Er:YAG Laser vs. Bur Preparations on Marginal Adaptation in Enamel and Dentin of Mixed Class V Cavities Restored With Different Restorative Systems

“…Since the vapor pressure (at 25 • C) for acetone is four times higher than that for ethanol, acetone is more volatile, potentially leading to more water-remnant droplets and thus instabilities and interferences with the polymerization reaction, causing blister formation or intensifying permeability of the adhesive layer, triggering hydrolytic degradation of polymers and collagen, which is potentiated by the acidic pH of the monomer (44)(45)(46)(47)(48)(49). It seems therefore to be crucial, next to a coordinated timing of solvent evaporation, to accelerate and improve water droplet removal and evaporation with strong air-drying of the adhesive system prior to polymerization, as acetone is evaporated much faster than water (50). These facts may support the hypothesis that differences in recommendations for air-drying may be at least partly responsible for the distinct performance of OBU and GPB in dentin.…”