Methods: Thirty-five patients aged 21-77 (mean=55) years (20 female, 15 male) with 103 defective restorations which were independently diagnosed during treatment planning, participated in the study. Patients were assigned to five groups, repair (n=10), sealing of defective margins (n=23), refurbishing (n=23), replacement (n=22), and no-treatment (n=25) groups. A modified Ryge Criteria that included marginal adaptation, anatomy, contact, secondary caries, and sensitivity was used to evaluate the restorations at baseline, 6-month, one-, two-, and seven-year recall exams. Degradation in any of the criteria was considered a failure. A survival analysis was conducted using the LIFETEST procedure in SAS (version 9.1, Cary, N.C.).
Results: Eighty-three (81%) restorations were examined at one-year, 81 (79%) at two-year, and 47 (46%) at seven-year recall exams. The number of degradations observed over time for available cases were as follows: marginal adaptation (repair=1, sealing=9, refurbished=7, replacement=10, monitored=9); anatomy (repair=0, sealing=6, refurbished = 7, replacement=4, monitored=6); contact (repair=0, sealing=3, refurbished = 3, replacement=3, monitored=7); secondary caries (repair=0, sealing=0, refurbished = 1, replacement=1, monitored=3); and sensitivity (repair=0, sealing=0, refurbished=1, replacement=2, monitored=3). The survival estimates for each treatment were: repair (.667), sealing (.725), refurbishing (.356), replacement (.659), and no-treatment group (.569). The p-value for the log-rank test of equality over treatment groups was .2046 while the p-value of the Wilcoxon test was .1776.
Conclusions: The study showed that some degree of degradation of restorations occurred in all treatment groups after the 7-year recall exam. However, the survival estimates showed no differences among the various treatment groups and the replacement group.
This study was supported by UF-DSR research grant #01042678.