COMPARISON OF THE MARGINAL INTEGRITY OF INVIVO AND INVITRO CLASS-II COMPOSITE RESTORATIONS

In the present study Class II resin composite restorations were placed under in vivo and in vitro conditions. For the in vivo part. Class II preparations were cut in teeth destined for extraction for orthodontic reasons. The preparations were completed with the gingival margin in enamel and restored using six different combinations restorative techniques and materials. The teeth were extracted after 4-6 weeks. In the in vitro part similar preparations were cut in extracted teeth and restored using the selected material-technique combinations. The in vitro specimens were thermocycled and mechanically loaded at 125 N for a total of 4000 cycles. All in vivo and in vitro samples were stored in a dye solution, sectioned and inspected for microleakage. Microleakage was observed in all the in vivo specimens with only 60% of the in vitro specimens demonstrating microleakage. These results indicate the limitation of laboratory investigations in predicting the microleakage performance of Class II composite resin restorations under clinical circumstances.