Necessity And Indications For Vertical Control In Skeletal Class 2

To assess the necessity of TAD-assisted vertical control in camouflage treatment for skeletal Class II hyperdivergent patients and to identify factors that suggest its use. This retrospective study analyzed adult skeletal Class II hyperdivergent patients treated at Peking University School and Hospital of Stomatology (2015–2020). Two groups were compared: maximum anchorage (MMA) alone and MMA with TAD-assisted vertical control (MMA+VC). Cephalometric and model superimpositions measured skeletal, dental, and soft-tissue changes, Key parameters included upper molar intrusion, mandibular plane angle, and Z angle. Multivariable regression explored the association between skeletal and dental modifications and soft tissue improvements. Both groups achieved significant sagittal correction, incisor retraction, and lip retraction (P<0.05). The MMA+VC group uniquely demonstrated significant maxillary molar intrusion (−2.25±1.03 mm) and mandibular counterclockwise rotation (−1.82±1.38°, P<0.05), which correlated with superior soft-tissue outcomes: Z-angle improvement (15.25 ± 5.30°, P < 0.05) and reduced chin thickness (−0.97±0.45 mm, P<0.05). Multivariate regression demonstrated that decreased mandibular plane angle and upper incisor inclination, coupled with improved chin projection, collectively drove Z-angle enhancement. TAD-assisted vertical control can achieve intrusion of approximately 2 mm for the upper first molars and induce mandibular counterclockwise rotation of approximately 1.8°. Moreover, it is especially important for patients without sufficient retraction of the upper incisors or a satisfactory chin shape.