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 x 10-15. The initial measurements of the restoration image were compared to the measurements of the new cavity preparatiom, in both instances excluding the site of failure. Intraclass 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. (C) 2001 Elsevier Science Ltd. All rights reserved.