COMPARISON OF MARGINAL FIT AND MICROLEAKAGE OF CERAMIC AND COMPOSITE INLAYS - AN IN-VITRO STUDY

The purpose of this in vitro study was to evaluate the marginal fit an d microleakage of four types of ceramic or resin composite inlays. Six ty extracted human third molar teeth were randomly assigned into four groups. MOD cavities without bevels were prepared. The mesiogingival m argin was cut in enamel, whereas the distogingival margin was placed b elow the amelocemental junction. The preparations and inlays were made according to the manufacturers' instructions. After acid-etching and treatment with a dentine bonding agent the inlays were cemented with d ual curing CEREC resin composite luting material. After placement and polishing 10 teeth of each group were thermocycled 2500 times between 14-degrees-C and 62-degree-C. Each tooth was bisectioned and from each part, one occlusal and three proximal sections of 75-100 mum thicknes s were cut and ground (EXAKT Cutting and Grinding system). The margina l discrepancy and the thickness of the luting cement were measured mic roscopically at each section and an average for each tooth was calcula ted. Considerable variation of marginal fit was seen, within inlays, a nd among different types of inlays. In general, the Vita Dur N inlays showed the best fit. e.g. the thickness of the luting cement for Vita Dur N was 114 mum occlusally and 119 mum mesiogingivally compared to 1 99 mum occlusally for CEREC and 219 mum mesiogingivally for Estilux. A t enamel margins, a tendency of less microleakage was seen for ceramic inlays compared to composite inlays.