Abstract
The purpose of this study was to investigate whether biting pressure and masticatory efficiency depended on the occlusion types in children with primary dentition, or not. The subjects were 130 children from 3 to 6 years of age. They consisted of 68 children with normal occlusion,19 children with deep bite,15 children with edge to edge bite,5 children with vertical open bite,19 children with horizontal open bite and 4 children with anterior cross bite. The masticatory efficiency all of the subjects was measured using the ATP spectrometric method and the bite force using the measuring system of the occlusal pressure (Dental Prescale®). Data for each occlusion types were compared with the normal occlusion group. Furthermore, the relationship between the bite force and masticatory efficiency and the relationship between the occlusal contact areas and masticatory efficiency were investigated among the groups of each occlusion type. The following results were obtained:
1. Masticatory efficiency in the deep bite group showed significantly lower values than in the normal occlusion group. There were no significant differences in masticatory efficiency between the groups of the other occlusion types and the normal occlusion group.
2. The values of the occlusal contact area and occlusal force in the deep bite group were significantly lower than in the normal occlusion group. In the posterior tooth site of each malocclusion group, the occlusal contact area, occlusal force and average occlusal pressure did not show significant differences compared with the normal occlusion group.
3. In the normal occlusion group, there were significant correlations between the bite force and masticatory efficiency (r=0.330) and between the occlusal contact area and masticatory efficiency (r=0.340). On the other hand, no significant conrrelation between these parameters was found in the malocclusion groups.
