A double labial-arch retaining appliance to retain the treatment effective of Class Ⅲ osteal malocclusion were introduced and used to retain 60 patients with Class Ⅲ osteal malocclusion. At the same time, 60 patients with Class Ⅲ osteal malocclusion were retained with conventional Hawley retainer as the control group. The results indicated that the double labial-arch retaining appliance has good effect to the retain of Class Ⅲ osteal malocclusion.
