Various morphologies of human models are modeled with various growth patterns to demonstrate the role of mandibular morphology on growth contributions to Class II corrections. Growth patterns are described by centers of mandibular rotation relative to the cranial base. Centers of rotation are used to determine several parameters of growth generated by a computer programmed to show growth effects. The direction and amount of condylar growth are held constant. With condylar growth constant, various centers of rotation of the mandible reveal that maximum Class II molar correction is present when the condyle is vertically located farthest from the molar. Of lesser importance, Class II corrections are greater when the condyle is anteroposteriorly closest to the molar.
Bibliographical noteFunding Information:
From the Division of Orthodontics, School of Dentistry, and Department of Mechanical Engineering, University of Minnesota, and Department of Growth and Development, School of Dentistry, University of California San Francisco. This research was supported in part by United States Public Health Service Research Grant DE-0352X and University of Minnesota Grant-in-Aid Research Fund 441-0325-4909-02. Correspondence and reprint requests should be addressed to Dr. Robert J. Isaacson. Department of Growth and Development, School of Dentistry. University of California at San Francisco. Calif. 94143.
- Class II corrections
- Mandibular shape
- centers of rotation
- growth projection
- mandibular rotation