Microleakage of Silorane Restorations in Er, Cr:YSGG Laser Prepared Cavities

Objective: To evaluate the microleakage of Class V Silorane and composite resin restorations at enamel and dentin interfaces following Er, Cr:YSGG laser preparation. Methods: Rectangular Class V cavities (4mm width, 3 mm height,2 mm depth) were prepared on the buccal or lingual surfaces of 20 extracted caries and restoration free human molar teeth with cervical margins located in dentin and the incisal margins in enamel. The teeth were then assigned to 4 groups (n=10). Group1: Diamond bur preparation + Silorane adhesive (3M ESPE) + Silorane (3M ESPE); Group2: Diamond bur preparation + acid etching + Single bond 2 (3M ESPE) + Filtek P-60 (3M ESPE); Group3: Er, Cr:YSGG laser preparation (5W, 85%air / 75% water) + Silorane adhesive + Silorane ; Group 4: Er,Cr:YSGG laser preparation + acid etching + Single Bond 2 +Filtek P-60. The cavities were restored with either of the restoratives according to the manufacturer's recommendations and polymerized with LED curing unit (Elipar, 3M ESPE). After polishing, the specimens were submitted to thermal cycling (1000 cycles;between 5-55 degrees C) followed by dye immersion. Leakage was evaluated under magnification (40X) based on a standard ranking. SEM evaluation of cavity – restoration interfaces of the respective test groups were made on cross section specimens. Data were subjected to Kruskal Wallis analysis. Results: The majority of the specimens were leakage free. Although dentin margins of laser prepared composite resin group (G 4) showed most leakage, there were no statistically significant differences among groups (P>0.05). There were no significant difference between enamel and dentin margins of all groups. SEM evaluation of cavity-Silorane (G 1-3) interfaces showed no gap formation. However laser prepared dentin-composite resin interfaces (G 4) exhibited gap formation. Conclusion: Both microleakage and SEM evaluations showed perfect sealing ability of Silorane restorations.