To evaluate the casting fixed Twin-block appliance on the clinical effects of growing children with skeletal Angle Class Ⅱ division 1 malocclusion.

30 patients with skeletal Angle Class Ⅱ division 1 malocclusion were treated by fixed casting Twin-block. Cephalometric data before and after the treatment were measured and analyzed.

Difference of SNA and U6-PTM between pretreatment and post-treatment was not statistically significant (P > 0.05), there was statistically significance of diminution in ANB, OJ or Wits appraisal which decreased after treatment and augment in SNB, Go- Gn, Co- Gn, L1-MP, Sn-A-UL、Li-Si-Pg' which changed after treatment of fixed casting Twin-block (P < 0.05).

Treatment of casting fixed Twin-block is effective in the early treatment of skeletal Angle Class Ⅱ division 1 malocclusion.