Comparison of microleakage of three acid-base luting cements versus one resin-bonded cement for Class V direct composite inlays.

Statement of Problem: Demineralized dentin beneath set cement may adversely affect microleakage under fixed restorations.
Purpose: Microleakage of direct composite inlays cemented with acid-base cements and a methyl methacrylate resin cement were evaluated to determine their effect on the integrity of the underlying hybridized dentin.
Materials and Methods: Sixty Class V box preparations (3 mm x 3 mm x 1.5 mm) were precisely prepared in previously frozen bovine teeth with one margin in enamel and another margin in dentin. Direct composite inlays (EPIC-TMPT) for each preparation were divided into 4 groups of 15 specimens each and cemented with 3 acid-base cements (control group): Elite, Ketac-Cem, Hy-Bond Carbo-Cem, and 1 adhesive resin cement: C&B Metabond. All specimens were stored in distilled water for 24 hours at 37 degrees C before immersion in 0.5% basic fuchsin for 24 hours. The dye penetration was measured on the sectioned specimens at the tooth-cement interface of enamel and cementum margins and recorded with graded criteria under light microscopy (Olympus Vanox-T) at original magnification x 50, 100, and 200. A Kruskal-Wallis and the Mann-Whitney test at P<.05 were used to analyze leakage score.
Results: All cementum margins of the 3 acid-base cements tested demonstrated significantly higher leakage scores than cementum margins for inlays cemented with the resin cement tested(P<.01). No leakage along the tooth-cement interface was found for inlays retained with the adhesive resin cement.
Conclusions: Within the limitations of this study, the 3 acid-base cements tested exhibited greater microleakage at the cementum margins than did the adhesive resin cement that was tested.