Crown morphologic abnormalities in the permanent dentition of patients with cleft lip and palate.

The purpose of this study was to investigate crown morphologic abnormalities in the permanent dentition of subjects with clefts and unaffected controls. This is a prospective study of 100 patients and 60 control subjects. The study was carried out at the Cleft Lip and Palate Center at the King Abdullah University Hospital and at the Maxillofacial Unit at Jordan University of Science and Technology during the period November 2003 to September 2005. Eleven kinds of crown morphology abnormalities commonly described in the permanent dentition were recorded using the Arizona State University Dental Anthropology System. There were 1525 teeth examined in 100 subjects with clefts, and 203 crown morphologic abnormalities were recorded, resulting in a mean of 2 abnormalities per individual. No significant difference between the unilateral and bilateral cleft lip and palate groups was found; however, the difference between the cleft group and the control group was highly significant. Crown morphologic abnormalities were more frequent in the maxillary cleft teeth than in the mandibular teeth and in the anterior teeth than in posterior teeth, with a statistically significant difference. The most frequently found abnormalities in subjects with clefts were peg-shaped maxillary incisors and missing hypocone, followed by excess mammelons. In conclusion, there was a significant increase in the frequency of crown morphologic abnormalities in individuals with clefts when compared with subjects without clefts. Crown morphologic abnormalities occurred throughout the entire dentition and did not follow any predictable pattern.