Agenesis of the permanent lateral incisor: distribution, number and sites.

Agenesis of the lateral incisor was examined in 112 patients (42 males and 70 females). The distribution of this condition was assessed according to site, symmetry of the anomaly and the number missing for both males and females. Hypodontia of both maxillary lateral incisors was the most common form of agenesis recorded, with the absence of lateral incisors in the maxilla occurring in 91 per cent of the sample studied. Hypodontia in the maxilla was recorded more frequently in females (61 subjects) than in males (30 subjects) at a ratio of 2:1 respectively. Absence of lower lateral incisors was rare.