Abstract
A malocclusion having a history of surgical repair for cleft lip and palate shows mandibular prognathism caused by maxillary deficiency in many cases, and also has more complicated problems of congenital missing and/or anomaly of teeth.
It is, therefore, critical to know the growth and developmental degree of the mandibule, which sometime overdevelops in comparison with the underdeveloped maxilla, when treatment is proceeded.
To investigate how the mandibule grows and develops in cleft lip and palate cases, a fusing time between epiphysis and diaphysis of the distal phalanx of the first digit was used as a standard. Materials used were serial cephalograms of 10 male and 10 female cleft lip and palate patients who had surgical repairs and of 14 males and 18 females having other malocclusions as controls.
Results:
1. A chronological age to reach a fusion of the distal phalanx of the first digit was 14 years and 8 months in males, and 12 years and 5 months in females for the cleft lip and palate group, and 14 years and 10 months, and 12 years and 10 months for male and female controls respectively.
There was almost no difference between the groups, while females were 2 years ahead of males as to the difference between the sexes.
2. As to the growth of mandibular length before and after fusion of the distal phalanx of the first digit, a large growth before fusion and a small growth after fusion were revealed in almost all cases examined irrespective of different sexes and groups, although some individual difference was observed.
3. The mandibular length at the fusion of the distal phalanx of the first digit was 119.6 mm in males, and 110.1 mm in females of the cleft lip and palate group, while it was 124.3 mm in males, and 115.2 mm in females of the control group, indicating that the length in the cleft lip and palate group was smaller than that in the control group for both sexes.
