Clinical evaluation of replacement of class V resin based composite restorations

Objectives: The purpose of this clinical study was to evaluate any increase in size of Class V resin based composite restorations that required replacement. Emphasis was placed on measurements of the loss of tooth structure in areas distant from the site of failure. Methods: 14 Class V restorations scheduled for replacement were recorded with pre-operative impressions and intra-oral photographs. Restorations were then removed and cavity preparations were completed. A second impression and photograph were taken and stone casts were prepared for each impression. The perimeter and area of each restoration and cavity preparation were measured with a video-based imaging system (Dage 725 CCD camera) equipped with a macro lens, at a fixed magnification of ×10–15. The initial measurements of the restoration image were compared to the measurements of the new cavity preparation, in both instances excluding the site of failure. Intra-class correlation coefficient (ICR) and paired t-test were used for statistical analysis. Results: A significant difference between the pre and post-operative measurements for both area (P=0.0125) and perimeter (P=0.003) was found. Conclusion: The study showed that replacement of Class V resin based composite restorations resulted in increased size of the cavity preparation in areas distant from the site of failure.