Tooth size in relatives of individuals with oligodontia.

Mesiodistal dimensions of teeth in 59 relatives of 26 patients with oligodontia were evaluated and compared with the size of teeth of a control group (n = 66). It was found that the teeth of relatives do show reductions in size even in relatives with a full permanent dentition. In male relatives with a full permanent dentition these reductions were significant for the central and lateral incisors, the cuspids, lower second premolar, upper first molar and lower second molar. For female relatives with a full permanent dentition these reductions were significant for central and lateral incisors, cuspids, first premolars and upper first and second molars. Reductions in tooth size are known to be associated with oligodontia. Therefore, in determining the mode of inheritance, measurements of the size of the teeth of both patients and relatives are important.