Microleakage in posterior composite restorations can be related to incomplete bonding, polymerization shrinkage and high functional stresses. As an early sign of restoration failure, margin leakage can lead to recurrent caries at the cavosurface interface. Objectives: The purpose of this investigation was to evaluate the effect of placement techniques on microleakage in posterior composite restorations. Methods: Two surface cavities were prepared to standard dimensions in recently extracted human molars. A packable composite P60^TM, and a flowable composite Filtek Flow^TM were used alone or in combination. Three restorative techniques were used: packable composite placed directly in 2-3 mm increments, flowable composite placed cervically and cured prior to restoration, flowable composite placed cervically without curing prior to restoration. Ten samples of each technique were thermocycled between 5 and 55 degrees Celsius for 500 cycles and stained with silver nitrate. The teeth were then sectioned and evaluated for depth of dye penetration using Image Pro Plus software. Results: The results for microleakage were: P60, 1.42(+/- 0.24 mm); P60 plus Flowable Cured, 1.27 (+/- 0.42 mm); P60 plus Flowable Uncured, 1.59 (+/- 0.47 mm). A one-way ANOVA/Tukey test at p<0.05 showed no significant differences between the three techniques. Conclusion: A lining of flowable composite cured prior to restoration had the least penetration, although the differences among the three techniques were not statistically significant. Funding was provided by an AADR Fellowship Award and the University of Michigan School of Dentistry Research Program.

Back to the Dental Materials: VIII - Others-Non-metallic Program
Back to the IADR/AADR/CADR 80th General Session (March 6-9, 2002)

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