Changes in occlusal contact area and average bite pressure during treatment of anterior crossbite in primary dentition.

The purpose of this study was to examine changes in functional parameters of patients with anterior crossbite in primary dentition during orthodontic treatment. Occlusal contact area (OCA), average bite pressure (ABP) and integrated occlusal load (IOL) were measured. Data obtained before the start of treatment (period A), data obtained when crossbite had improved (period B) and data obtained when the appliance had been removed (period C) were compared. OCA showed the lowest value in period B, and then gradually increased. ABP increased until period B and then declined or became constant. OCA and IOL showed significant differences in periods A and B and periods B and C (p < 0.05). The results suggest that about 6 months is required for stability of the occlusion and acquisition of function in the new occlusion after improvement of crossbite.