If a cross bite involves a number of teeth, for example a unilateral buccal cross bite, removable appliances can be used to correct this. The sequence of events is shown in Figures 5a-f. Adams cribs are generally placed on the first premolars and the first permanent molars and a midline expansion screw is incorporated into the base plate. This midline screw is opened 0.25 mm (one quarter turn) twice a week until the cross bite is slightly overcorrected. Posterior buccal capping can also be used to disengage the bite and prevent concomitant expansion of the lower arch. Once the cross bite is corrected the buccal capping can be removed and the appliance used as a retainer to allow the buccal occlusion to settle in. Occasionally two appliances will be needed if a considerable amount of expansion is needed.
Was this article helpful?