Influence of resin remover on micro-tensile bond strength of resin composite to coronal dentin

Aim: This invitro study assessed the effect of resin remover used for removal of resin based endodontic fillings on the microtensile bond strength of resin composite to coronal dentin
Materials and methods; Freshly extracted sound human molars, that were extracted for periodontal reasons not correlated with this study, were disinfected and prepared for microtensile bond strength testing. The occlusal surfaces were ground to expose coronal dentin. In half of specimens, dentin was treated with resin remover for eight minutes. In the other half, dentin was not treated (control group). Tetric N ceram composite blocks were bonded to occlusal surfaces of all specimens using total etch adhesive system; Tetric N bond universal. After 24 hours storage, specimens were sectioned to provide a total of 40 beams; 20 beams for each gourp. Beams were tested for microtensile bond strength using universal testing machine and failure mode was recorded. The tooth/restoration interface was examined using scanning electron microscope.
Results: resin composite bonded to dentin pretreated using resin remover revealed a statistically higher bond strength than that bonded to untreated dentin. Mixed adhesive cohesive failures and cohesive failure in composite was predominant in resin remover dentin pre-treated groups compared to control group that revealed mostly adhesive failure or cohesive failures in dentin. Scanning Electron microexamination showed more penetration of resin tags and more obturation of dentinal tubules in specimens treated with resin remover.
Conclusion; usage of resin remover showed promising results considering bonding to coronal dentin which demands further research in this field.