[Some properties of various composite resin inlay products]

Several problems associated with materials and clinical techniques are pointed out for posterior composite resin restoration. One of the solutions to these problems is the application of the indirect composite resin inlays. Three kinds of products for composite resin inlay are being marketed at present. We examined the mechanical properties, surface roughness and radiopacity for each product. Inlay/Onlay (Ivoclar), Brilliant D.I. (Colténe) and CR Inlay (Kuraray) were used in this study, and composite resin inlays were fabricated in accordance with the manufacturers' instructions. The highest values of mechanical properties after immersion in water for 24 hours are shown below: table; see text The mechanical properties of the composite resin inlay, subjected to thermal cycling at 4 degrees C and 60 degrees C for 3 minutes each for 5,000 cycles, tended to decrease in comparison with those immersed in water for 24 hours. Inlay/Onlay showed the smallest surface roughness (Ra), i.e. the best smoothness value below: table; see text The radiopacity was highest for Inlay/Onlay with Brilliant D.I. and CR Inlay being successively lower.