The purpose of this study was to evaluate the difference and relationship between the slope of articular eminen and the inclination of upper and lower incisor teeth, which are related to the functional stability of occlusion in man, bular protrusion, according to Ricketts´ facial types, by the use of lateral cephalogram and SAM2 articulator in 68-ad normal occlusion without tooth missing, orthodontic treament and occlusal equilibration.
The results of this study were as follows.
1. The angle of articular eminence slope to occlusal plane in brachyfacial type was steeper than that in dolichofac type, but the angle of articular eminence slope to "SN plane and FH plane was not different between facial type
2. The upper incisor axis in dolichofacial type was steeper than that in brachyfacial type, but lingual surface sic of upper incisor was not different between facial types.
3. In all samples there was a positive correlation between the angle of articular eminence slope and the ling surface slope of upper incisor to SN plane and FH plane, and in mesofacial type there was a positive correlati between the angle of articular eminence slope and the lingual surface slope of upper incisor to SN plane, FH pla and occlusal plane, and in brachyfacial type there was a positive correlation between the angle of articular eminen slope and the lingual surface slope of upper incisor to occlusal plane.
4. In all samples there was a positive correlation between the angle of articular eminence slope and the angle Dc-Gn to SN plane, and in mesofacial type there was a positive correlation between the angle of articular eminen slope and the angle of Dc-Gn to occlusal plane, and in brachyfacial type there was a positive correlation betwe the angle of articular eminence slope and the angle of Dc-Gn to SN plane and FH plane.
5. In all samples there was a positive correlation between the angle of Dc-Gn and the lingual surface slope of upper incisor to SN plane and FH plane, and in mesofacial type there was a positive correlation between the angle of I)c-(:n and the lingual surface slope of upper incisor to SN plane.
6. In all samples and facial types there was a negative correlation between MP to T axis and condylar incisal angle.
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