Examinations were based on lateral cephalometric changes in sagittal extent. For this purpose, The FR-3 appliance was tried out on total 13 patients (5 female and 8 male) Who have skletal Angle Class III malocclusion due to maxillary indadequacy. The changes in the sagittal direction on lateral cephalograms and the findings obtained as a resuit of treatment, were compared with the usual grow up and maturation values. Then, whole data were evaluated biostatistically. Consequently, all results showed that, although FR-3 appliance can be used on this type of malocclusions, good patient cooperation and knowing the individual optimal grow-up models are extremly important and necessary.

Keywords: Functional Regulator, Angle Cl III Malocclusion, Cephalometrics