[Evaluation of the effect of invisible correction and SGTB in the treatment of mandibular retrusion].

Purpose: To compare the clinical effects of invisible correction and SGTB in two-stage treatment of mandibular retrusion.

Methods: Eighty-five patients with bony mandibular regression who did not pass the peak of growth and development were selected. Among them, 40 cases were guided by invisible correction and 45 cases were guided by SGTB functional correction. Lateral head X-rays before and after treatment were measured, and the effect before and after treatment was compared by SPSS 16.0 software package.

Results: After treatment, the SNB angle and NP-FH (face angle) increased and the ANB angle decreased in both groups, all of which had significant changes(P＜0.001). At T1, the changes of SNB angle, ANB angle and NP-FH angle in the invisible group were smaller than those in the SGTB group(P＜0.05). The difference between MP-FH angle and MP-SN angle before and after treatment was greater in the SGTB group than in the invisible group(P＜0.001).

Conclusions: In patients with receding mandible before the peak of growth and development, the mandible was significantly moved forward after orthodontics. Both invisible orthodontics and SGTB promote changes in the position of the mandible, improves coordination between the upper and lower jaws. In the control of the posterior teeth in the vertical direction, the invisible group is stronger than the SGTB group.