The functional regulator (FR-3) of Fränkel.

This article describes the construction of the FR-3 appliance classically used in cases of Class III malocclusion characterized by maxillary skeletal retrusion. Included is a description of proper impression technique, construction bite registration, preparation of the work models, and a complete description of the fabrication of the FR-3 appliance. Specific steps in the clinical management of this appliance are also presented. The cephalometric records of three patients treated with the FR-3 appliance are then presented.