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In order to analyze the occlusin of intercuspation with maximun bite force, fifteen healthy adult subjects with the ages 23 to 27 were studied (Group1 ; 5-normal occlusion with Angle’s Class1, Group2 ; 5-Angle’s Class2 malocclusion, Group3 ; 5-Angle’s Class3 malocclusion). Head Position was fixed with occlusal plane paralleling to horizontal line and occlusal registration record was made with polyether rubber impression material(Ramitec, ESPECo. West Germany). After all subject were trained for maximum intercuspation at least 5 times, occlusal registration procedure was repeated for this study. Lower posterior rubber occlusal registration records were sliced with 1㎜ thickness using precision metal sliding channel (Hitachi Ind. Co., Japan). Gross sectional drawings were traced from occluding view of upper and lower posterior teeth on the rubber slices using digitizer, and superimposed for the determination of each drawing distance(Superimposed Rubber Pattern Method). Based on superimposed rubber pattern drawings, total area of occlusal view, sum of each area of the 5 divided occlusal contact provinces and its ratio, total area and number of occlusal contact area were determined to elucidate occlusal stability in the normal and abnormal occlusion groups. The data were analysed by t-test (p=0.05) to determine statistical significance. The obtained results were as follows : 1. Group1 showed the largest standard area with occlusal view of the lower posterior teeth and Group3 showed the smallest area. There was a significant difference between Group2 and Group3 (p=0.025), and Gropu1 was not statistically different for both Group2 and Group3. 2. Means and ratio of the under 2.0㎜ area(D) and ratio showed 197.49㎟, 59.76％ in Group1, 188,69㎟, 56.10％ in Group2, and 174.23㎟, 55.76％ in Group3. The results that Group1 has the most area／ratio and Group3 has the least area／ratio can be considered Group1 is the most advantageous for masticatory effective area, and Group3 is the least adnantageous. 3. Means and ratio of the under 1.0㎜ area(C) were 198.96㎟, 42.65％ in Group1, 123.06㎟, 46.58％ in Group2, and 92.24㎟, 29.52％ in Group3. These data means that Group1 is the most advantageous in terms of masticatory effective area and Group3 is the least. 4. Means and ratio of the under 0.5㎜ area(B) were 86.68㎟, 26.68％ in Group1, 62.98㎟, 18.71％ in Group2, and 36.44㎟, 11.66％ in Group3. These can also be considered Group1 is the most advantageous for masticatory effective area and occlusal stability. 5. Means and ratio of the under 0.05㎜ area(A) were 30.92㎟, 9.21％ in Group1, 14.31㎟, 4.25％ in Group2, and 7.59㎟, 2.43％ in Group3. The area ratio of the each subject group was (4.1) : (1.9) : (1) and the data of the under 0.05㎜ area has the intimate relationship with inter-group and intra-group data／ratio. 6. First molar showed the most occlusal contact points in all subject group and Group1 showed somewhat uniformly distributed occlusal contact point except first premolar. In Group2, all contact point in posterior teeth showed significantly reduced distribution except first molar. Group3 showed evenly distributed contace points in first and second molars
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