December 2006

Objective: The aim of this study was to determine the prevalence and pattern of hypodontia and the extent of congenital malformation in the permanent teeth of a sample of Jordanian adults. Material and Methods: Clinical examinations were carried out on 1045 dental patients aged 16 to 45 years to record any congenital absence of teeth except 3rd molars and to note any crown shape or size deformities affecting the upper lateral incisor. The congenital absence of permanent teeth was confirmed by taking complete dental history and orthopantomograms. Impacted teeth and teeth lost as a consequence of extraction or trauma were recorded as present. Results: The prevalence of hypodontia was found to be 5.5% of the sample and the lower second premolar was the most frequently missing tooth. The number of missing upper lateral incisors was significantly higher than that of lower lateral incisors, (p<0.05). Peg-shaped and reduced size upper lateral incisors were observed in 2.3% and 2.9% of the sample respectively. There were no significant differences according to gender, location of tooth according to arch or side of the jaw and hypodontic pattern.Conclusion: The prevalence of hypodontia was 5.5%, that of peg-shaped lateral incisor was 2.3% and that of reduced crown size was 2.9%. Key words: Hypodontia, Jordanians, peg-shaped, prevalence