Comparison of Different Protocols for Performing Adhesive Restorations in Primary Teeth - A Retrospective Clinical Study

Purpose: To examine the influence of different adhesive restoration protocols on the survival of composite resin restorations in primary teeth. Materials and Methods: This study included 601 patients at risk of caries (319 males and 282 females), with a mean age of 6.6 years (range: 1 to 13 years) and an average need for 3.6 restorations per patient (range: 1 to 20). The mean observation period was 1.3 years (± 1.4), with a maximum of 7 years. Six different adhesive restoration protocols with respect to etching, adhesives, and composite materials were analyzed. The statistical analyses included descriptive analyses and a Cox regression model from which hazard ratios (HR with 95% CI) for protocols and possible predictors were calculated. Results: The mean dmft was 6.6 (± 4.0), which indicates a high risk population. Secondary caries was the most frequent reason for loss of restoration in this study (52.2%). Out of 2146 restorations, 368 failed; the mean annual failure rate was 13.2%. Adhesive restoration protocols that employed a self-etching system performed significantly better (HR range: 1.0 to 1.8) than did the etch-and-rinse system (HR range: 1.8 to 2.8). Protocols using only flowable materials had a moderately increased probability of failure. Conclusion: With respect to the practice-based study design, young age, and high risk of caries in this population, comparatively high failure rates were observed for direct composite restorations in primary dentition, but adhesive restoration protocols using self-etching adhesives in combination with universal composites yielded a higher probability of survival. Keywords: retrospective, composite resin, adhesive restoration protocol, restoration, longevity, deciduous dentition