RESUMO
A comparative study was made on the chewing movements of normal occlusion and skeletal class III malocciusion. Thirty normal occlusion sybjects and twenty skeletal class III malocciusion patients were given chewing gums for the study ; using BioPAK system, the chewing movement on the frontal plane was recorded and analyzed. With a typical chewing path chosen representing each subject, chewing width, poening distance, poening and closing angles, maximum opening and closing velocities were observed. Seven characteristic patterns were classfied based on the types of chewing paths. The followings are the results : 1. Compared with the normal occlusion group, the skeletal class III malocclusion group showed more varied and vertical chewing patterns. 2. In comparision of chewing widths, skeletal class III malocclusion group showed marrower path than the mormal occlusion group(P0.05). 4. In opening and closing angles, skeletal class III malocclusion group showed more acute angles than the normal occlusion group(P0.05). 6. In the classification of chewing movement pattern, Type IV(chopping type)of skeletal class III malocclusion group showed a higher rate with 25.0% over 3.3% of normal occlusion group.