Abstract
Objective: Pediatric dentists prefer restorative materials with a high bond strength and fewer clinical stages. Cention N can be used in the bulk technique. It can release fluoride ions, calcium, and hydroxide. This study compared the microleakage of two types of composite resins: Cention N and Tetric N Ceram bulk-fill composite resin in class II restorations (box only) of deciduous teeth. Materials and Methods: In this experimental investigation, 50 class II restorations (box only) were prepared in extracted deciduous second molars. Then the teeth were divided into two groups based on their restorative materials. The first group was restored with Cention N and the second group with bulk-fill Tetric N Ceram composite resin. The Tetric N Bond adhesive was used before placing the restorative materials in both groups. The samples were cut and investigated under a stereomicroscope to determine microleakage after thermocycling and staining with silver nitrate. Two samples from each group were prepared for observation under an electron microscope. Then the data were analyzed using the nonparametric Mann-Whitney test. Results: The mean percentage of dye penetration into the gingival wall was not significantly different between the two groups under the investigation. Conclusion: Using Cention N with adhesive yielded favorable results in terms of microleakage, and it is recommended for class II restorations in deciduous molars.