Hypodontia and Tooth Formation in Groups of Children With Cleft, Siblings Without Cleft, and Nonrelated Controls

OBJECTIVE: To compare the occurrence of hypodontia, dental age, and asymmetric dental development in children with cleft with their siblings and a nonsibling control group. SUBJECTS: The sample consisted of 54 children with cleft (aged 4.2 to 13.1 years), who had at least one sibling available for an orthopantomogram, 63 siblings without cleft (aged 4 to 14.9 years) and 250 controls without cleft (aged between 4 and 14.9 years). METHOD: Hypodontia, dental age, and asymmetric dental development were assessed on panoramic radiographs of the children with cleft, the siblings without cleft, and the control children without cleft. RESULTS: Both the cleft (p <.001) and the sibling group (p <.05) showed a significantly higher frequency of hypodontia and a significantly higher occurrence (cleft p <.01 and sibling group p <.001) of asymmetric dental development, compared with the control group. Only a small, but insignificant, delay in dental development could be found in the cleft and the sibling group. CONCLUSIONS; The cleft subjects with siblings showed a significantly higher occurrence of hypodontia and asymmetric dental development than the noncleft control group. This may suggest a genetic component for the occurrence of hypodontia and asymmetric dental development.