The Goettingen "Pro-Stab" removable plate system. A retrospective cephalometric study of the effects of a new Class II treatment appliance.

The new removable double-plate appliance has characteristics which provide for efficient treatment of Class II malocclusions: virtually unimpaired speaking and free breathing seem to support patient compliance. The sagittal activation is easy to change and the plates for the upper and the lower jaw can be worn separately or in combination, with and without the "Pro-Stab" rods even with different wearing hours (modular concept). Evaluation of lateral head films taken at the beginning and at the end of treatment (mean interval 1.45 years) of 40 patients provided information on therapy-induced changes, which were then compared with results of recent publications. The data obtained with the new system indicate similar results as with bite-jumping appliances and headgear-supported activators. Inhibition of the sagittal development of the upper jaw and retrusion of the upper incisor segment have been primarily responsible for the correction of Class II malocclusions. The effect as regards the sagittal position of the lower jaw has been moderate. In comparison with similar appliances, protrusion of the lower incisors was more pronounced when treated with the Goettingen Type I "Pro-Stab" removable plate system.