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Relative Clinical Success of Bis-Acryl Composite Provisional Crowns
Carla Kozmacs1, Vanessa Baumann2, Oskar Bunz1
1Department of Prosthodontics and Dental Technology, Faculty of Health, Witten/Herdecke University, Witten, Germany.
Abstract:
The high demands on the clinical performance of a single-tooth provisional restoration necessitate that said performance be examined. The authors evaluated 24 teeth evaluated. Two test groups received bis-acrylic composite for provisional crowns (n = 12) and a single-unit, self-supporting, malleable, light-curing composite crown (n = 12). Final crowns (n = 24) served as paired controls. Evaluation of clinical success was measured using previously selected subcategories of FDI criteria. Statistical analysis was performed using McNemar's Test (α = 0.05). The null hypothesis of no improvement of the definitive crown relative to the provisionals was rejected at the 5% significance level (McNemar's P value <.001, Bonferroni corrected). Of the provisional crowns, 75% received a clinically insufficient valuation, while only 8% of the definitive crowns did. The authors concluded that, independent of the manufacturing process, a bis-acrylic composite provisional crown cannot serve as a replacement for a conventionally manufactured definitive crown.
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