Abstract
We encountered four cases (father, son, and two daughters) diagnosed as partial anodontia without congenital ectodermal dysplasia.
The results were as follows.
1) Case 1: A l3.9 year-old female with_??_which were congenitally absent.
Case 2: An 18.3 year-o1d male with_??_which also.
Case 3: A 10.9 year-o1d female with_??_which also.
Case 4: A 45.8 year-old male with_??_which also.
2) The upper lateral incisor of the children showed signs of having a rudimentary form and also smaller mesiodistal diameters of the crown. In Case 1 a large number of teeth were missing, and the permanent teeth erupted were sm a ller than in the other cases. Especially, the upper lateral incisors showed signs of having conical shaped teeth and the upper 1st molars showed also s igns of the upper 3rd molars.
3) In Case 1, the underdeveloped growth of the maxilla resulted in the formation of mandibular prognathism and cross bite. Thus for improvement of them, expansion of the maxilla was performed, and chin cap for mandibulla was applied. Dentures were placed in the missing regions of Case 3, and the m asticatory functional rate was recovered.
4) From the observations on the phenotypic level, it was considered that the cause of the partial anodontia is from the presence of a dominant gene. In Case 1, it was also considered that the poor condition of mother's womb during pregnancy had hastened the congenital absence of teeth.
