Frequency of restoration replacement in posterior teeth for U.S. Navy and Marine Corps personnel.

STATEMENT OF PROBLEM: There are no recent data that describe the replacement rates of resin composite and dental amalgam restorations placed by US Navy dentists. Information is needed to provide the best possible care for our military personnel which would minimize the probability of dental emergencies, especially for those who are deployed.

PURPOSE: The purpose of this study was to determine if the frequency of posterior restoration replacement in military personnel differed based on the type of restorative material utilized.

METHODS AND MATERIALS: Data contained in dental records in an observational study (retrospective cohort) were evaluated to identify resin composite and dental amalgam restorations placed by navy dentists in posterior teeth. The status of all erupted, unerupted, missing, and replaced teeth was documented. The type and condition of all existing restorations were recorded for each posterior tooth. Investigators reviewed 2921 dental records, and of those, 247 patients met the criteria for inclusion in the study. A total of 1050 restorations (485 resin composite and 565 amalgam) were evaluated.

RESULTS: A Cox proportional hazards model was adjusted for number of tooth surfaces restored, caries risk, and filled posterior surfaces at initial exam. The overall rate of replacement for all restorations in the sample was 5.7% during the average 2.8-year follow-up. No significant elevation of risk for restoration replacement existed when comparing resin composite and amalgam. Both the number of restored surfaces and caries risk status were independent risk factors for replacement. When restoring multisurface cavity preparations, providers placed amalgams by an approximate 2:1 ratio over resin composites for this study population.

CONCLUSION: The results for this study show that no difference existed in the rate of replacement for amalgam vs resin composite. When restorations increased from just a single occlusal surface to additional surfaces, the rate of replacement was elevated and statistically significant for both materials. A higher caries risk status was also significant in elevating replacement rates for both materials.