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Objective: To evaluate the effects of the Chinese Ni-Ti coil springs appliance on distalization of maxillary molars and the reciprocal effects on the anchorage teeth. Methods :Twenty four adolescent patients(12 boys,12 girls) with Class Ⅱ malocclusion were selected and the coil springs appliance was used during the treatment. Pre and postdistalization lateral cephalometric radiographs were analyzed and compared. Results: The average time for the correction of Class Ⅱ molar relationship was 4. 6 months. And the mean distance of molar distalization was 4.4 mm. The Chinese Ni-Ti coil springs also demostrated less tipping and better bodily movement of maxillary molars. Conclusion: This study suggests that the Chinese Ni-Ti coil-springs appliance distalizes the upper molar significantly, while there is no remarkable loss of anchorage because of patients wearing headgear with J hooks at night and Class Ⅱ elastics in the day time.