Influences of genetic and environmental factors on developmental dental anomalies: a twin study

Panoramic radiographs of twin and non-twin pediatric patients were analyzed to determine the prevalence of developmental dental anomalies. The concordance between monozygotic (MZ) and dizygotic (DZ) twin pairs was assessed to investigate the relative contributions of genetic and environmental factors to these anomalies.

Panoramic radiographs from 419 pairs of twins and 838 non-twin patients, aged 7 to 13 years, who attended the clinic between 2017 and 2023, were examined for developmental dental anomalies. These anomalies were classified by number, size, shape, and positional anomalies. Categorical data were analyzed using the chi-square test, and the concordance of anomalies within twin pairs was evaluated using pairwise concordance and tetrachoric correlation analyses.

Developmental dental anomalies were observed in 33.2% of the twin group, 23.3% of the control group, 31.4% of the MZ twin group, and 33.8% of the DZ twin group. A statistically significant difference was identified in the prevalence of number anomalies between the twin and control groups (p = 0.025), whereas no significant differences were found for size, shape, and positional anomalies between these groups (p > 0.05). Analysis of MZ twin pairs revealed statistically significant concordance and tetrachoric correlation for anomalies such as hypodontia, dens invaginatus, taurodontism, impacted teeth, and infraoccluded primary molars.

The findings of our study indicate that genetic factors play a more significant role in the etiology of hypodontia, taurodontism, impacted teeth, and infraoccluded primary molars.

These findings present novel targets for future research aimed at elucidating the genetic and environmental determinants underlying developmental dental anomalies.