Abstract: Objective To observe the effects of transmission straight wire technique on treating adolescents with Class Ⅱ division 1 malocclusion by cephalometric analysis. Methods 40 (24 females,16 males) subjects treated with transmission straight wire appliance were selected, whose mean age was 13.2 years old. By analyzing the cephalograms of all subjects, soft and hard tissues before and after treatment were compared. All data were statistically analyzed by SPSS 19.0. Results After a mean treatment time of 12 months, the molar relationship and facial profile were obviously improved. According to cephalograms, U1SN, ANB, U1RL, U6RL were decreased, but L1MP, L1RL, L6RL were increased. There was no significant change in other items. Conclusion The transmission straight wire appliance has a good effect on patients with class Ⅱ division 1 malocclusion, and it can also take advantage of intraoral anchorage and lightwire to move teeth quickly and obtain correct torque efficiently.

Key words: transmission straight wire appliance, Angle class Ⅱ division 1 malocclusion, cephalometric