Evaluation of the effect of pre- and post-topical fluoride treatment on marginal microleakage of resin composite and glass ionomer restorations

Fluoride has popularly been used as a caries prevention agent. This study evaluates the effect of fluoride gel (APF) on microleakage before and after restoration placement of tooth colored restorations.

Eighty-four standard class V cavities were prepared and the specimens were randomly divided into three groups (n=14): Group 1- APF employed before cavity preparation; Group 2- APF employed after completed restoration; Group 3- without APF application (control). Buccal cavities were restored with OptiBond Solo adhesive system and Herculite XRV composite resin and lingual cavities were restored with Fuji II LC Glass ionomer. After finishing and polishing, thermal cycling followed by immersion in 0.5% basic fuchsin dye was performed. Then, the specimens were sectioned and microleakage was ranked under magnification (×40). Two teeth of each group were treated for SEM observation. Data were subjected to statistical analysis using Kruskal Wallis and Wilcoxon tests.

There were significant differences in enamel marginal microleakage of composite (14.68) and glass ionomer (16.00) restorations (p=0.02), but they similarly proceeded in dentinal margins (0.921). The dentinal margins (2.50) of the glass ionomer in control group showed more leakage than the enamel margins (0.00) (p=0.04). All experimental groups; either before or after fluoride therapy, showed similar microleakage in the enamel and dentinal margins.

APF employed was ineffective on microleakage before and after composite resin restoration placement. Microleakage could increase in enamel margins of resin modified glass ionomer restorations with fluoride therapy protocol.