Polymerization shrinkage of resin composite at the margin can seriously decrease the longevity of the restoration. Three direct restorative techniques were evaluated for their effects on microleakage. Sixty Class V cavities were prepared in extracted human maxillary molar teeth. The cavities were restored with resin composite placed in one bulk increment, resin composite and a beta-quartz insert, or resin composite and a prepolymerized resin composite ball insert. After they were themocycled and placed in 0.5% basic fuchsin for 24 hours, the specimens were sectioned and examined for microleakage. The restorations with a prepolymerized ball of resin composite exhibited significantly more microleakage than did restorations with a beta-quartz insert or restorations inserted in bulk.