Influence of cement type on the marginal adaptation of all-ceramic MOD inlays

Objective: The aim of this study was to investigate the in-vitro marginal adaptation of all-ceramic class II inlays which were luted with conventional multi-stage pre-treatment cements and one new type of cement, which requires no conditioning. Methods: The marginal adaptation of 56 all-ceramic inlays was determined with scanning electron microscopy and microleakage tests. The marginal integrity of each tooth was evaluated at cement–dentin and cement–enamel junctions, with regard to the transitions between tooth-cement and cement–inlay. The inlays were luted on human molars with two resin cements, one compomer, one resin modified glass-ionomer and one new resin cement in accordance with the manufactureʹs recommended pre-treatment. Light- and chemical-curing modifications were investigated. All tests were performed after thermal cycling and mechanical loading (TCML). Results: For the resin cements and the new material the marginal integrity was higher than 90% before and after TCML. The marginal adaptation was between 55–80% for the resin modified glass-ionomer and lower than 20% for the compomer. The microleakage was lower than 20% for all cements, only the compomer showed values up to 100% penetration. Significance: The difference in marginal integrity between the new universal resin cement without any tooth pre-treatment and conventional resin cements after total-etching, priming and bonding was not significant. Resin GIC may be used with restrictions and compomer cement should not be used with all-ceramic class II inlay restorations.