Influence of Eugenol‑based materials and cleaning procedures previously to resin composite restoration on microleakage after 1‑year storage

Abstract

The interference of eugenol on the adhesive systems and composite polymerization could promote a higher marginal microleakage. This could be reduced by mechanical and chemical cleansing. The objective of this study was to evaluate the influence of the previous use of eugenol-based materials to a permanent restoration on the marginal microleakage. The influence of mechanical cleansing associated with chemical cleansing with chlorhexidine gel was also evaluated. Non-eugenol endodontic sealer and temporary material and mechanical cleansing was used as a control. Eighty bovine incisors were endodontic treated and divided into eight groups (n = 10) according to the sealer, temporary material and removal method. The specimens were temporarily restored and stored for 1 week at 37 °C and 100 % relative humidity, followed by definitive restoration and one-year storage at the same environment. The teeth were then sealed, immersed in silver nitrate at 50 % for 2 h and sectioned to have the microleakage qualitatively and quantitatively visually analyzed under a stereomicroscope at 45×. The percentage data were submitted to an ANOVA and Tukey’s test, and the scores were submitted to a Kruskal-Wallis and Dunn’s test at 5 % of the significance level. There was no difference between the groups when mechanical removal was made (p > 0.05). When chlorhexidine was used, the group that used endodontic eugenol based material as a sealer and the resin-based material as a temporary restoration showed less microleakage than the other (p < 0.05). All groups showed less microleakage when chlorhexidine was used instead of solely using mechanical removal (p < 0.05). For scores, when the eugenol based sealer was combined with resin-based temporary material, and when the resin sealer was combined with eugenol based temporary material using chlorhexidine, a lower median was found (p < 0.05) compared to all other groups. Eugenol showed no influence, and chlorhexidine gel showed to be effective in reducing microleakage.