Abstract
This study was conducted to investigate the relationship between mandibular bone mass and masticatory dysfunction. Twenty-five CLP patients (CP group) with posterior cross-bite before orthodontic treatment were used as subjects and thirty females (NC group) with acceptable occlusion in the posterior region served as the controls.
Mandibular bone mass was evalua ted in terms of mandibular cortical width (MCW) measured at the mental region on panoramic radiographs. The relationship between the MCW and craniofacial morphology was also investigated by use of correlation analysis. The results were as follows:
1. Mean of MCW was 3.3mm for the CP group, and 3.6mm for the NC group. MCW was significantly smaller in the CP group than in the NC group.
2. In the CP group, the position of the maxilla was significantly more posterior in relationship with smaller ramus of the mandible and larger gonial and mandibular plane angles than the NC group.
3. MCW exhibited a negative correlation with gonial angle in the CP group. A negative co rrelation with anterior facial height and mandibular plane angle and a positive correlation with posterior/anterior facial height ratio were observed in the NC group.
These results suggested that masticatory dysfunction during childhood substantially affect internal structure of the mandible in terms of bone mass as well as the craniofacial morphology.
