Eruption of Permanent Teeth in Mongoloid Children and Their Sibs

Eruption constants for the permanent dentition were determined in 212 mongoloid children and 124 of their unaffected sibs. Eruption of the permanent teeth in sibs was like that of other normal children. Mongoloid children resembled their sibs in general characteristics of tooth eruption, but showed a consistent tendency toward later mean ages of eruption for each tooth type.