Cephalometric changes associated with treatment using the activator, the Fränkel appliance, and the fixed appliance

Abstract

Treatment with the activator, the Fränkel appliance, and the edgewise appliance was compared in three separate groups; each group consisted of twenty-five nonextraction cases of Class II, Division 1 malocclusion. Hard- and soft-tissue profile changes caused by growth and treatment were assessed by means of pretreatment and posttreatment lateral cephalograms. Anterior movement of A point was 1.6 mm more in the activator group than in the fixed-appliance group. The most anterior point on the maxillary incisor moved 1.5 mm more distally in the fixed-appliance sample than in the functional groups. Among the three groups, the activator sample showed the most anterior movement of the mandible (2.3 mm); the fixed group showed the least (0.6 mm). The fixed-appliance group showed more posterior rotation of the mandible than the activator group. However, relative to cranial base, the movement of the mandibular symphysis was not statistically different in the three groups. There were little differences among the treatment groups with regard to changes in the soft-tissue profile. In clinical terms, there was a remarkable similarity in the changes that occurred in the three treatment groups.