The purposes of this study were to classify the anteroposterior and vertical skeletal pattern of normal occlusion samples into specific types with factor and hierarchical cluster analysis, and to evaluate the range and limit of skeletal relationships that permit the establishment of normal occlusion via natural dentoalveolar compensation.
Lateral cephalograms of 294 normal occlusion samples were measured, as selected from 15,836 persons through a community dental health survey who cooperated in record taking. Using a factor analysis, two factors representing anteroposterior and vertical skeletal relationships were extracted from 18 skeletal measurements. Then cluster analysis classified the skeletal patterns into nine types. The means and the standard deviations of 8 anteroposterior skeletal measurements and 10 vertical skeletal measurements were determined and comparisons of these measurements among the types were performed. ´;´he results obtained in this study showed that the range of normal occlusion included very diverse anteroposterior and vertical skeletal re ationships.
16. Yang WS, Chang Yf, Kim TW. A new approach to use overbite depth indicator in orthodontic diagnosis. Kor J Orthod 1992 : 22 17-30.
17. Siriwat PP, Jarabak JR. Malocclusion and facial morphology : is there a relationship? An epidemiologic study. Angle Orthod 1985 55 :127-38.
18. Isaacson JR, Isaacson RJ, Speidel T, Worms FW. Extreme variation in vertical facial growth and associated variation in skeletal and
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