Relationship between positional differences in occlusion and craniofacial growth in the rat

Abstract

I investigated the effect of positional differences in the center of occlusal force on the craniofacial growth in rats. Two hundred and four 3-week-old male F344/Jcl rats were divided into three groups. The vertical dimension of occlusion was raised 1mm at the first molar in group A, and 1mm on the third molar in group P, while group C was untreated controls. At 15 weeks of age, cephalometric analysis showed a hyperdivergent facial type in group P and a hypodivergent type in group A. The mandibular condyle in group P was smaller and rounder than in group A. The weight of the masticatory muscles was not significantly different. These results indicate that occlusal position influences the rotational growth pattern of the face in rats.