DOI: 10.36347/sjams.2017.v05i06.053

Pages: 2330-2336

Using posterior composite restorations will cause some problems, since in these trends high viscosity and polymerization shrinkage exist. To reduce these problems, several methods have been suggested. Hence, this study aimed to compare the gingival microleakage of Class II composite restorations that cover apical to the cemento-enamel junction (CEJ), through three restorative methods, Conventional, Open sandwich and Snow plow. This in vitro study included 40 class II cavities in 20 extracted intact human premolars. Gingival margins were located within 1 mm apical to CEJ. The samples were divided into four groups randomly and were filled through different methods. Group 1: P60 Packable composite. Group 2: RMGI (Resin modified glass ionomer, Fuji II LC) with thickness of 1mm. Group 3: in this group flowable composite (Filtek Flow) with thickness of 1mm was cured. Group 4: flowable composite with 0.5 mm thickness without curing, along with 0.5 mm packable composite, which then they cured together. In all groups, remained space of cavities was packed by packable composite. All samples were thermo- cycled and then were immersed in 0.5% basic fuchsin and evaluated dye penetration. Data were analyzed through Kruskal-Wallis and Mann-Whitney test at p < 0.05. In group 1 microleakage was significantly higher than other groups, and no significant differences were found between groups 2, 3 and 4. The results revealed that, the application of intermediate layers between resin composite and dental substrates results to decrease gingival microleakage.