Effect of salivary contamination on marginal microleakage with a one-bottle adhesive system

Abstract

Objective: Evaluate the effect of saliva contamination on microleakage of class V composite restorations. Material and methods: Thirty cavities class V (3.0mm × 2.0 mm × 2.0 mm) were prepared in sound bovine incisors with oclusal margin in enamel and cervical in dentin. The teeth were randomly assigned to 3 Groups (n = 10). In the Group I (control), the adhesive system SingleBond (3M ESPE) was applied according to manufacture’s instructions. On group II, the preparations were contaminated with fresh saliva, after the acid etching. On group III, the preparations were contaminated similar to group 2, but the saliva was air dried during 5s to remove the contamination. All cavities were restored with hybrid composite, applied in two oblique increments. After 24 hours, the teeth were thermocycled (500×, 5°-55º, 60s each cycle), covered with sticky wax and fingernail, accommodated in 0.5% basic fuchsine for 4h, washed, dry and sectioned. The extension of microleakage was analyzed with scale of 0-4. The data were submitted to Kruskal Wallis test. Results: The median score in enamel margins were: Group I = 0, Group II = 4, Group III = 0. In the enamel, Groups I and III presented less microleakage than Group II (p = 0.0339). In the dentin margins the median score were: Group I = 1, Group II = 4, Group III = 4. Groups I (control) presented less microleakage than Group II and III (p = 0.0103). Conclusion: Salivary contamination has a negative effect on marginal sealing. Considering enamel margins, remove the contamination with air dried seems to be an efficient procedure to reestablish marginal integrity.
UNITERMS: dentin bonding; acid etching; microleakage.