Dental anomalies in patients with familial and sporadic cleft lip and palate.

Based on the frequency of occurrence of cleft lip and palate (CLP) in a family, a distinction has been made between familial and sporadic CLP. It was presumed that the genetic predisposition in familial CLP is high, while in sporadic CLP environmental factors play an important role. This study describes the possible relationship between the incidence of dental anomalies and the genetic predisposition of CLP in both the deciduous and permanent dentition. Dental anomalies were studied in 100 CLP patients and 38 control subjects. Neither the number of dental anomalies, nor the numbers of missing and supernumerary teeth differed significantly between familial and sporadic cases. A comparison between subjects with and without CLP showed a significant difference in the morphology of the dentition of the upper jaw. This difference was quantitative rather than qualitative. This study indicates a direct relationship between cleft formation and formation of the teeth, irrespective of the genetic predisposition and the severity of the cleft (i.e. uni- or bilateral).