The purpose of this study was to investigate the effect of the loss of both first molars on the mandibular growth of growing rats. Twenty nine Sprague-Dawley rats four weeks old were divided into two groups: the first group served as the conrtol, and ...
The purpose of this study was to investigate the effect of the loss of both first molars on the mandibular growth of growing rats. Twenty nine Sprague-Dawley rats four weeks old were divided into two groups: the first group served as the conrtol, and both first lower molars were extracted from the second groups. The experimental animals were sacrified at 4 and 8 weeks after extraction of the lower first molars. The changes of the rats' mandibular growth following the extraction of the lower first molars were examined biometrically from dry bone specimens.
The finding were as follows:
1. Extraction of lower both of the first molar produced inhibitory effects on the growth of the mandible of the growing rats.
2. Extraction of the lower first molar of the rats did not change the original shape of the mandible.
3. Among the factors affecting mandibular growth, the presence of the teeth, that is, maintenance of occlusal function was essential.
4. Extraction of the mandibular first molar did not change the general growth of rats' whole bodies.