2001 Volume 21 Issue 4 Pages 435-442
To evaluate the effects of orthodontic treatment on mastication in patients with openbite, we measured the following indices before active treatment (Openbite group) and during retention (Treatment group) in openbite patients in comparison with female normal occlusion (Non-openbite group) : 1) overjet (OJ) and overbite (OB); 2) cutting ability of the anterior teeth, using soft plate wax; 3) occlusal contact area, occlusal force, and mean occlusal pressure, using dental Prescales®; 4) chewing gum masticatory test; and 5) mandibular movements during gum chewing, using a Gnathohexagraph®.
1. The mean OJ and OB were 2.4 and 2.3 mm in the Non-openbite group. The mean OJ and OB were 1.4 and-1.9 mm in the Openbite group and 1.7 and 1.5 mm in the Treatment group.
2. The cutting ability of the anterior teeth in the Non-openbite and Treatment groups was significantly greater than those Openbite group.
3. The occlusal contact area and the occlusal force in the Non-openbite group were significantly greater than those in the Openbite and Treatment groups.
The mean occlusal pressure in the Treatment group was significantly greater than in the Non-openbite group but was not significantly different from Openbite group.
4. The masticatory ability in the Non-openbite group was significantly greater than those from both the Openbite and the Treatment groups, but they did not significantly differ between the Openbite and Treatment groups.
5. The masticatory rhythm did not significantly differ among the 3 groups.
These results suggest improvement in open bite and acquisition of the cutting ability of the anterior teeth after orthodontic treatment in the openbite patients.
