In Vitro Microleakage at beveled occlusal margins in primary molars

Aim: The objective of this study was to evaluate the microleakage at the beveled occlusal margins in primary molars and compare to non beveled margins. Methods: Two occlusal preparations each having one non beveled (GI) and one beveled occlusal margins (GII) were cut in each of 20 primary molars (n=40). All samples were restored with TPH hybrid composite resin (DENTSPLY) according to manufacture's instructions. The specimens were maintained in distilled water at 37˚C for 07 days. After that, the restorations were polished and the tooth apices were sealed with epoxy resin and nail varnish was applied to within 1 mm of restoration margins. Then, the teeth were sectioned mesio-distally with a slow speed saw, providing two sections per restoration (n=80). Microleakage was rated with consensus of two evaluators (Kappa ponderate=0,812) with a microscope (40x) as following: 0 - no microleakage; 1 – enamel microleakage; 2 – dentin microleakage; 3 – pulp microleakage. Data were analyzed by Mann Whitney test. Results: A statistically difference was determined between non beveled and beveled margins in primary molars (p<0.001). Conclusion: In this investigation, the amount of microleakage was cavity design dependent. The non beveled occlusal margins produced less leakage than beveled margins in primary molars.