Dentoskeletal changes in adult Class II division 1 Herbst treatment--how much is left after the retention period?

The aim of this study was to assess dentoskeletal changes following Herbst-Multibracket treatment in adult Class II division 1 patients. The subject material comprised 15 adult Class II division 1 subjects exhibiting a Class II molar relationship more than or equal to 0.5 cusps bilaterally or more than or equal to 1.0 cusps unilaterally and an overjet more than or equal to 6.0 mm. The average treatment time was 9 months (Herbst phase) plus 13.9 months (Multibracket phase). Lateral headfilms from before treatment (T1), after Herbst-Multibracket treatment (T2), and after at least 24 months of retention (T3) were analysed using the 'sagittal-occlusal analysis' (Pancherz, 1982) as well as standard cephalometric variables. During the treatment period (T2-T1), molar relationship, overjet (-6.2 mm), and overbite (-2.1 mm) were successfully corrected. The Class II jaw base relationship improved (ANB -0.8 degrees and Wits -1.1 mm) and the hard as well as soft tissue profile straightened (NApg +1.5 degrees, NsNoPgs +1.2 degrees, and NsSnPgs +1.5 degrees). During the retention period of on average 35.5 months (T3-T2), the amount of occlusal relapse (T3-T2) was small (less than or equal to 1.0 mm). The jaw base relationship (ANB +0.3 degrees and Wits +0.7 mm) and the profile convexities (NApg -0.3 degrees, NsNoPgs -0.6 degrees, and NsSnPgs +0.6 degrees) deteriorated slightly. Following the retention period, only minimal amounts of skeletal changes contributing to Class II correction in adult Herbst-Multibracket treatment were retained. Thus, adult Herbst-Multibracket treatment results in mainly dental changes, which however, showed good stability.