MARGINAL BREAKDOWN OF FIRED CERAMIC INLAYS CEMENTED WITH GLASS POLYALKENOATE (IONOMER) CEMENT OR RESIN COMPOSITE

The marginal breakdown of fired porcelain inlays in vivo, luted with e ither a dual-cured resin composite or a glass polyalkenoate(ionomer) c ement, was evaluated by scanning electron microscopy. Immediately foll owing polishing (baseline) and after 1 year, replica impressions were made of the occlusal and proximal margins of two inlays, one cemented with the resin composite and the other with the glass ionomer cement, in each of 12 patients. At baseline the best marginal adaptation was o bserved along the proximal margins of the composite luted inlays, whil e occlusally glass ionomer luted inlays showed better marginal qualiti es than the composite luted inlays. At 1 year the composite luted inla ys showed significantly better marginal adaptation than the glass iono mer luted ones at all interfaces. The greatest breakdown was observed occlusally, especially in the glass ionomer luted inlays. Gap sizes va ried proximally between 83 and 100 mu m and occlusally between 107 and 143 mu m. Severe ditching was observed occlusally in the glass ionome r luted inlays. The overall marginal quality was significantly better for the inlays luted with the resin composite both at baseline and aft er 1 year.