The skeletal and dental effects of two kinds of Herbst appliances

Abstract Background The dentoskeletal effects of Herbst appliances were reported in several studies. The purpose of this study was to evaluate, using cephalometry, skeletal and dental effects of treatment using two types of Herbst appliances in adolescents with Class II division 1 malocclusion and mandibular retrognathism. Methods Seventy-five consecutive adolescents (treated groups: A [steel crowns] and B [acrylic splints]; group C: control) were monitored for 12 months. Lateral radiographs were obtained at baseline (T1) and at the end of the observation period (T2). Cephalometric variables were analyzed using parametric tests. Results The results of the two treatment groups were different from those found for the control group. Maxillary growth was restricted, whereas mandibular growth was greater, which resulted in a better sagittal relation. The analysis of dentoalveolar aspects revealed that overjet was reduced due the maxillary incisors tipped palatally and flaring of mandibular incisors, vertical control of maxillary molars and mesial movement of mandibular molars. The three groups had similar extrusion of mandibular molars and preservation of mandibular morphology and facial pattern. Conclusion Treatment with two types of Herbst appliance resulted in changes that improved sagittal skeletal and dental relations, regardless of growth. The control of vertical growth pattern did not depend on the type of the Herbst appliance is used; however, in cases of lack of space in the maxillary arch, the Herbst appliance with steel crowns was more efficient.