Influence of finishing time on marginal sealing of direct restorations

Objective: to verify the influence of finishing and polishing procedures on microleakage of Class V restorations using two different composite resins. Methods: Sixty Class V cavities were prepared in sound human premolars. One cervical margin was placed in enamel (1mm to the CEJ) and one in dentin (1mm below the CEJ). The teeth were randomly divided in the follow groups: group I were restored with micro-hybrid resin composite Opallis (FGM) – immediate polishing and finishing procedures, group II were restored with Opallis (FGM) – polishing and finishing procedures after 24 hours, group III restored with nanoparticules resin composite Filtek Supreme XT (3M ESPE) – immediate polishing and finishing procedures, group IV with Filtek Supreme XT (3M ESPE) – polishing and finishing procedures after 24 hours. The restored teeth were stored in water at 37°C and subjected to thermocycles (5-55C, 500x, 1min.) before being immersed in 0,5% basic fucsin for 24 h. The teeth were then washed, dried, sectioned and the extent of die leakage was measured and recorded using a 0 - 4 scale. Data were analyzed with the Kruskall Wallis test (p<0.05). Results: The medians for scores were: G1 – enamel:0, dentin:1; G2 – enamel:0, dentin:0; G3 – enamel:1, dentin: 2; G4 – enamel:0, dentin:1. Comparing the composite resins, Opallis resulted in lower leakage scores on both enamel and dentin margins. Finishing and polishing procedures after 24 hours resulted in better sealing capacity. Conclusion: The type of composite resin and the time of polishing and finishing procedures influence the microleakage on direct restorations.