Periodontal bone loss of teeth with metal posts. A radiographic study.

Periodontal bone loss was compared in teeth with metal posts and contralateral teeth without metal posts by means of intraoral radiographs. 250 subjects with a high standard of dental awareness and a great number of teeth retained were included in the study. The periodontal bone loss was calculated from the ratio of the distance from bone margin to apex (bone height) and the distance from crown tip to apex (tooth length). Intra-individual differences between experimental and control teeth were statistically analyzed with the Student paired t-test. 96 subjects (38%) had > or = 1 teeth with root posts. In all, 172 teeth with posts were found, i.e., on average 1.8 teeth per subject. The means +/- SEM of the ratio bone height to tooth length in experimental and control teeth were 0.52 +/- 0.007 and 0.56 +/- 0.006, respectively. The difference was statistically highly significant (P < 0.001). Statistically significant differences were found for incisors, premolars and molars. Regression analysis indicated more severe bone loss for teeth with longer posts. The results suggest that the periodontal bone support of teeth with metal posts is inferior to that of teeth without metal posts.