Globodontia in the otodental syndrome.

A family of Polish extraction was studied in which massive, globe-shaped posterior teeth were found in a father and two of his sons, similar to those described in a previous family in which persons with this type of teeth also had a high-frequency sensorineural deafness. The audiograms in this family showed high-frequency air-conduction thresholds in the father and one son with globodontia and in other relatives without the tooth defect. The other son with abnormal teeth had a normal-appearing audiogram. Absence of premolar teeth and yellow-white spots of local hypomaturation of enamel on canine teeth were also findings in this kindred, as reported or observed in other kindreds. The disorder illustrates the problem of variable expressivity of a trait which makes it difficult to predict the risk of having an affected child when only one feature of a syndrome is present in a relative of a fully affected patient.