Clinical Comparison of Three Esthetic Full-Coverage Restorations in Primary Maxillary Incisors at 12 Months

Purpose: The purpose of this study was to compare the 12-month clinical outcomes of primary maxillary incisors restored with composite strip crowns (CSCs), NuSmile preveneered stainless steel crowns (PVSSCs), and NuSmile zirconia crowns (ZCs). Methods: A total of 135 teeth in 49 two- to four-year-olds with early childhood caries were randomly assigned to crown groups. Demographic and tooth-related variables at baseline and 12 months were assessed by calibrated examiners. Fisher's exact or chi-square tests were used to test associations (P<0.05). Parental satisfaction of crown esthetics was evaluated by questionnaire. Results: Children were, on average, 3.4 years old, female (55 percent), and had a mean decayed, missing, and filled primary teeth (dmft) index score of 10.6. At 12 months, crown retention was significantly lower for CSCs versus PVSSCs or ZCs (79 percent, 100 percent, and 95 percent, respectively; P=0.002). Partial and complete loss of material was significantly higher in CSCs than PVSSCs or ZCs (29 percent, 11 percent, and zero percent, respectively; P<0.001). CSCs presented with increased marginal discrepancies and color change (P<0.001). Most parents were very satisfied (87 percent); those dissatisfied were concerned with the color of CSCs and PVSSCs (63 percent versus 37 percent; P=0.005). Conclusions: Composite strip crowns showed significantly reduced clinical success in retention, durability, marginal adaptation, and color compared to preveneered stainless steel crowns or zirconia crowns. Parental esthetic satisfaction was highest for NuSmile ZCs.