Abstract
Panoramic radiographs were used to survey the resorption of the alveolar ridge and the mandible of the edentulous subjects and to compare the vertical position changes of the mental foramen before and after the loss of teeth.
The results are as follows:
1. The vertical position of the mental foramen was described 0.590 for male and 0.636 for female subjects by the use of the vertical relative ratio (ratio of the distance from the inferior border of the mandible to the center of the mental foramen versus to the distance from the inferior border of the mandible to the upper edge of the alveolar crest through the center of the mental foramen vertically). It was significant for age and sex.
The vertical relative ratio is proved to be increasing with age, 0.0026 for male and 0.0013 for female subjects.
2. The distance from the center of the mental foramen to the inferior mandibular border was not significant with difference of age, but significant with sexual difference.
The valuale deviations were considered existing both between the edentulous and the dentulous, and male and female subjects.
