Comparative Evaluation of Microleakage of Different Class V Cavity Preparation Restored with Composite in Primary Molars: An In Vitro Study

Abstract

Objective: To compare the effect of the cavity design and the location of the gingival wall, on enamel and cementum on the microleakage of Class V composite resin restorations in primary molars. Materials and Methods: Class V cavity was made on the buccal surface of sixty sound primary mandibular second molar in this study. The teeth were divided into two main groups: Group A (Kidney shaped cavity) and Group B (Rectangle shaped cavity). Each group was also subdivided into two subgroups, Subgroup A 1 ; Kidney shape with gingival margin on enamel, Subgroup A 2 ; Kidney shape with gingival margin on cementum, Subgroup B 1 ; Rectangle shape with gingival margin on enamel and Subgroup B 2 ; Rectangle shape with gingival margin on cementum. After restoring all cavities with 3M™ Single Bond Universal Adhesive and Filtek™ Z250 XT (3M ESPE) composite, a dye penetration test was performed to evaluate the microleakage of occlusal and gingival margins. Results: Regarding the cavity design, a significant difference was found between the rectangle-shaped cavity design (1.1±1.09) and the kidney design (0.733±0.94). Regarding the location of the gingival margin, there was a statically significant difference between margins below the Cemento-enamel junction (2.30±0.98) and those above (1.20±1.13). Conclusions: Lowering the surface area of the cavity, as in the Kidney shape, helps greatly in minimizing the microleakage of composite restorations. Moreover, keeping the cervical margin in enamel as possible aids in the reduction of microleakage and saving the marginal integrity.