Objectives: This split-mouth, double-blind, randomized controlled study evaluated the clinical performance of composite restorations in Class I beveled margin cavity preparations in primary molars.
Methods: A total of 94 Class I cavity preparations were performed in the carious primary molars of 32 children aged 4-10 years. Two cavity designs were used: conventional conservative preparation (G1) and modified preparation with cavosurface bevel (G2). All teeth were restored using TPH Spectrumtrade mark. The restorations were evaluated by two calibrated investigators at baseline, 6, 12 and 18 months using slight modified USPH criteria. The visible plaque index and fiber optic transilumination (FOTI) were also used. The data were statistically evaluated using Wilcoxon and Friedman tests (p<0.05). The rank correlations between secondary caries, visible plaque index and FOTI were obtained using Pearson correlation (p<0.01).
Results: Of the 94 restorations performed and evaluated at baseline, 76 restorations were available after 18 months. Seventy-three restorations were considered as clinical success, 10 were censored for drop out reasons and 5 were lost by natural exfoliation. Four restorations failed by secondary caries and two failed by marginal adaptation discrepancies. For all evaluation there was difference between the baseline, 6, 12 and 18 months (p<0.05) but there were no statistically significant difference in G1 and G2 for any criteria evaluated (p>0.05) at any period of the study. The visible plaque index was correlated to secondary caries.
Conclusion: Bevel cavity design preparations did not improve the success of composite restorations in primary molars over 18 months.