Self-reported periodontal disease in a Virginia twin population.

To investigate the contribution of genetic factors in the etiology of periodontal disease, questionnaire data were collected on 4,908 twin pairs included in the population-based Virginia Twin Registry. A history of periodontal disease was reported in 420 individuals who were members of 116 monozygotic (MZ) and 233 dizygotic (DZ) twin pairs. The mean age at diagnosis in this sample was 31.4 +/- 0.7 years and was significantly earlier in females than males (30.1 vs. 33.0 years, P < 0.025). Proband-wise concordance rates were 0.38 for MZ and 0.16 for DZ twins. There were no differences in concordance rate between same and opposite-sexed dizygotic twins. These findings provide evidence that genetic factors make an important contribution to risk for adult-onset periodontal disease.