MICROLEAKAGE OF TOOTH-COLORED RESTORATIONS WITH A BEVELED GINGIVAL MARGIN

Objective: Microleakage of tooth-colored restorative systems was teste d in preparations with and without beveled gingival margins. Method an d materials: A resin composite, Z-100, and two ''compomer'' restorativ es, Dyract and Geristore, with their accompanying adhesive systems, we re placed in nonretentive cervical cavity preparations (at the cemento enamel junction), with and without a beveled gingival margin (dentin o r cementum) and beveled occlusal (enamel) margins in extracted bovine teeth. Microleakage was assessed as the ratio of the extent of methyle ne blue dye penetration at the tooth-restoration interface to the leng th of the wall. Results: Z-100 restorations, without a gingival bevel, exhibited significantly less microleakage along the gingival wall and less microleakage overall than did the other materials. Dyract restor ations,without a gingival bevel and placed without a surface condition er displayed greater microleakage overall than did the other groups. C onclusion: With all materials, Class V restorations with gingival beve ls displayed greater microleakage than did nonbeveled margins.