The skeletofacial growth pattern pre- and post-dentofacial orthopaedics. A long-term study of Class II malocclusions treated with the Herbst appliance.

The purpose of this investigation was to analyse cephalometrically the skeletofacial growth changes before and after dentofacial orthopaedics in 17 male subjects treated with the Herbst appliance. Herbst therapy was performed during an average time period of 7 months. The pre- and post-treatment periods in each subject were of equal lengths and amounted to an average of 31 months. No treatment was performed during the two control periods. When comparing the growth changes during Herbst treatment with those during the pretreatment control period it was found that: maxillary growth was inhibited and redirected; mandibular growth was increased; anterior mandibular growth rotation was arrested; sagittal intermaxillary jaw relationship improved; the skeletal profile straightened and the Go angle increased. During the post-treatment period several of the treatment changes reverted. The results of the study indicated that dentofacial orthopaedics using the Herbst appliance had only a temporary impact on the existing skeletofacial growth pattern.