Effects of mini-implant anchorage on mandibular rotation and esthetic outcomes in hyperdivergent skeletal Class II malocclusion treatment

Objectives: This research aimed to investigate the effects of mini-implants (MIs) on mandibular position and changes in lower face height, as well as their relationship with the position of the maxillary molars and incisors in the camouflage treatment of patients with hyperdivergent skeletal Class II malocclusion. Material and Methods: This retrospective study included 27 patients aged 15–38 years. The hyperdivergent patients were diagnosed with skeletal Class II malocclusion and treated with tooth compensation, tooth extraction, posterior repositioning of the maxillary incisors, and anchoring with MIs. Cephalometric analyses of these patients were performed before (T1) and after (T2) treatment. Measurements were taken at each treatment stage and analyzed. Results: Significant correlations were observed in the mandibular position and lower face height ( P < 0.05). The GoGnSN angle decreased (−1.05 ± 1.61°), the ANS-Me distance reduced (−1.98 ± 4.76 mm), and the NBaPtGn angle increased (1.67 ± 4.08°). In addition, the vertical height position of the maxillary first molar significantly decreased (6M-FH, −1.61 ± 3.74 mm), while the vertical height position of the maxillary incisor increased (U1-FH, 1.48 ± 2.11 mm). Conclusion: During the camouflaging treatment of patients with hyperdivergent skeletal Class II malocclusion using MIs anchorage, MIs helped intrude the maxillary first molar and extrude the maxillary incisor, leading to a difference in a mandibular counterclockwise rotation. Controlling the rotation of the lower jawbone helps create an improved esthetic for the patient after treatment.