Correlations of hypodontia in children with isolated cleft palate

A total of 251 children with isolated cleft palate were examined. Orthopantomograms, taken at the age of 6-12 years, were used in the detection of hypodontia of the permanent teeth, excluding the third molars. The findings were: 1. Familial history of clefting has no pronounced effect on the prevalence of hypodontia; 2. The prevalence of hypodontia was significantly higher in children with conical elevation of the lower lip than in those without it (40% to 25%), and increased with increasing extension of the cleft; 3. Cleft palate was associated with conical elevation and/or hypodontia in 56% of the subjects. The same etiological factor or factors seems to be responsible for the formation of the cleft, for conical elevation, and for hypodontia.