contemporary orofacial science

en Evaluation of Microtensile Bond Strength in Indirect Composite Restorations to Deep Dentin using Two Different Bonding Systems at Different Decoupling Times دندانپزشکی ترمیمی Operative dentistry پژوهشي Research <div style="text-align: justify;">Background: Composite resins are widely used in restorative dentistry, yet polymerization shrinkage remains a significant challenge. This study aimed to evaluate the microtensile bond strength of indirect composite restorations to deep dentin with two different adhesive systems, considering varying decoupling times. Materials and Methods: This experimental study involved 72 extracted molar teeth divided into six groups. Groups 1, 2, and 3 used Optibond FL, while groups 4, 5, and 6 used SE Bond. In groups 1 and 4, the bonding agent was applied followed by decoupling with time (DWT) and a 1 mm thick flowable composite. Groups 2 and 5 had a 0.5 mm composite applied, allowed a 5-minute DWT, then added another 0.5 mm composite. Groups 3 and 6 involved bonding and curing with a 1 mm composite but no DWT. All samples were restored with ENA Temp Micerium, and composite blocks were cemented. Micro-tensile bond strength was measured by applying a 500 N force until beam failure. Data were analyzed using ANOVA and Tukey's test (α = 0.05). Results: Both Optibond FL and SE Bond adhesives, in combination with DWT, significantly increased the micro-tensile bond strength. Application of DWT at both stages (post-bonding and after the 0.5 mm flowable composite) resulted in higher micro-tensile bond strength compared to the groups without DWT. Conclusion: The use of DWT significantly enhances the micro-tensile bond strength, and the timing of decoupling does not significantly affect the bond strength. Additionally, no significant differences were observed between the two types of bonding systems used.</div> 13 21 http://cofs.khuisf.ac.ir/browse.php?a_code=A-10-1-49&slc_lang=en&sid=1 Arezoo Islami 1003194753284600843 1003194753284600843 No Department of Operative Dentistry, Faculty of Dentistry, Isf.C, Islamic Azad University, Isfahan, Iran Mohammadreza Malekipour 1003194753284600844 1003194753284600844 Yes Department of Operative Dentistry, Faculty of Dentistry, Isf.C, Islamic Azad University, Isfahan, Iran Mehrdad Kazemian 1003194753284600845 1003194753284600845 No Department of Operative Dentistry, Faculty of Dentistry, Isf.C, Islamic Azad University, Isfahan, Iran Mona F Rabiei 1003194753284600846 1003194753284600846 No Department of Operative Dentistry, Faculty of Dentistry, Isf.C, Islamic Azad University, Isfahan, Iran