Abstract:

One of the main problems in assessing the mode of action of various treatment modalities is the method of measuring the treatment change. The purpose of the present study was to develop a cephalometric method that would permit a detailed evaluation of the individual growth processes (skeletal and dental) that contribute to the overall change in occlusal relationship. The change in molar relationship was resolved in five components, i.e. translation of the maxilla, of the upper molar, of the mandible, of the lower molar, and rotation of the mandible. These movements were recorded using regional superimposition of various structures, with the aid of a computer program. Derotation of the mandible was performed to remove any confounding effects of total mandibular rotation on the interpretation of the measurements. The results show that assessment of treatment effects can be carried out by comparison of the five resulting vectors.