RESUMO
mastication is basically regulated by central pattern regulator(CPG) of brain system target organ output from CPG is modulated by oral sensory feedback. anterior cross bite pattern infuluence the feedback mechanism and change muscle activity and jaw movement. .The purpose of this study was to investigate diffemce anterior cross bite group from normal group. the selected sample groups were 30 normal patient, 30 anterior cross bite patient. EMG and EGN of Biopak system were used for this study The following results were obtained 1. In resting state of mandible, anterior cross-bite showed the high r muscle activities in all the muscle.(exeeption:left digastric muscle) than normal group. 2. In clenching state, No significant difference in muscle activities of normal group and anterior cross bite group was noticed 3. In swallowing state Normal group showed the higher muscle activities in left and right masseter muscle, right posterior temporal muscle. 4. In maximum opening and closing velocity, normal group showed the higher value than anterior cross-bite. 5. In the mean value of the maximum operiing,the maximum anterior-posterior movement from centric-occlusion, the lateral deviation from centric-occclusion, normal group showed the higher value than anterior cross-bite group.