Document Type : مقاله‌های پژوهشی

Authors

• Parvin Khadem ¹
• Maryam Shams Nooraie ²
• Haleh Heshmat ³
• Mohamad j Kharrazi Fard ⁴

¹ Assistant Professor, Department of Operative Dentistry, School of Dentistry, Islamic Azad University, Tehran Branch, Tehran, Iran

² Dentist, Tehran, Iran

³ Assistant Professor, Department of Operative Dentistry, Dental Material Research Center, School of Dentistry, Islamic Azad University, Tehran Branch, Tehran, Iran

⁴ Research Member of Dental Research Center, Tehran University of medical Sciences, Tehran, Iran

Abstract

Introduction: Polymerization shrinkage and the resultant microleakage are still the problems with composite resin restorations. To overcome these problems, new low-shrinkage composite resins have been introduced by different manufacturers. The aim of this study was to compare microleakage in two low-shrinkage composite resin, Filtek-Silorane and GC-Kalore with two conventional composite resins, Filtek-Z250 and GC-Gradia.
Materials & Methods: In this experimental study, round cavities 5 mm in diameter and 1 mm in depth, were prepared on the middle of the buccal surfaces of 40 human third molars and divided into 4 groups (n=10). In group 1, the cavities were filled with Filtek-silorane composite resin and the relevant adhesive. In groups 2, 3 and 4, the cavities were filled with Filtek-Z250, GC-Kalore and GC-Gradia composite resins, using Adper Single Bond Plus bonding agent. After thermocycling and immersion in AgNO3, the samples were sectioned to evaluate dye penetration under a stereomicroscope (×10) at enamel margins and at cervical dentin contacting cementum. Data were statistically analysed with Kruskal-Wallis, Wilcoxon and Mann-Whitney tests (α = 0.05).
Results: There were not significant differences at enamel margins between the 4 groups. However, at cervical margins, microleakage in Filtek-Silorane composite resin was significantly lower than Z250 and Gradia composite resins (p value = 0.05). Microleakage with Kalore was significantly less than that with Gradia composite resin. In all the 4 groups, microleakage at cervical margins was significantly higher than that at occlusal margins.
Conclusion: There were no significant differences in microleakage at occlusal margins between all the composite resins. The highest and lowest microleakage at dentin margins was related to GC-Gradia and Filtek-Silorane silorane, respectively.
Key words: Composite resins, Methacrylate, Microleakage.