Early Failure of Class V Restorations in General Dental Practice

A wide range of materials is available to restore Class V lesions, but there is little clinical evidence on survival from dental practice to guide clinicians in appropriate selection. Objective: To identify the factors associated with early failure of Class V restorations in general dental practice. Method: 7 UK dentists, members of a West-Midlands practice based research group (BRIDGE), each recorded information on 100 consecutively placed Class V restorations. This included patients' details; materials used; tooth and cavity features; occlusion, and placement techniques. The survival of these restorations was assessed at routine recall visits. Data from restorations lost within two years was compared with those surviving beyond two years for any statistically significant differences using Chi square and appropriate follow-up tests (p=0.05). Results: Data on 642 restorations were available. 89 (13.9%) restorations had failed within two years. A significantly greater proportion of restorations placed under NHS funding failed within two years compared with those funded privately (p<0.001). The percentage of early failures among practitioners ranged from 0% - 30.3%, but this can be partially explained by the relative numbers of private and NHS patients seen by each dentist. There were fewer early failures for cavities not entirely within dentine (p<0.001); where there was prior caries (p=0.001); no moisture contamination (p=0.013), and when prepared with a bur (p<0.001). Compomer restorations had a higher proportion of early failure than other materials (p=0.025). Conclusions: Some clinical and operative factors influence the early survival of Class V restorations. Further analysis is necessary to establish whether these factors are also the root cause of the increased proportion of early failures associated with the method of treatment funding and with individual clinicians.

Supported by a grant from the BDA Shirley Glasstone Hughes Memorial Fund.