2007年8月，我們曾報導一位戽斗的洪同學，國小時經過第一階段面罩式下頷矯正頭套 (Face Mask / 又稱反拉式矯正頭套Reverse pull Headgear)，將上頷前拉(protraction)，改善門牙錯咬狀況後，國中時再接著進行第二階段固定式牙套矯正治療。
[Objective] The incidence of Angle Class III malocclusion in Taiwan is about 3~5%. The most common reason for their parents seeking orthodontic treatment is anterior cross bite. For early orthodontic treatments, face-mask or chin–cap or some removable appliance were often suggested. An Angle Class III boy with anterior cross-bite was treated with face-mask in Phase I then using fixed appliance to complete Phase II treatment. And a 13-year long term follow-up result will be discussed.
[Case] Clinically it is not uncommon to see young patients with anterior cross-bite. Early orthodontic Phase I treatment was often recommended. Treatment of choices included face-mask or chin–cap or some functional appliance. This case report described the treatment for a 10 year-old boy who has Angle Class III malocclusion with anterior cross-bite. The treatment plans included: Phase I therapy with face-mask, and Phase II treatment with fixed appliance.
[Discussion] After 1 year of face-mask treatment, the anterior cross-bite was corrected and satisfactory profile change achieved. Owing to moderate crowding, Phase II treatment completed with Class I occlusion after four first premolar extraction via fixed appliance. (Treatment changes—SNA: 78 °to 80°; SNB: 79 °to 78°; ANB: from -1°to 2°; Maxilla CCW rotation, palatal plane & functional occlusal plane flattened). And the 13-year post-treatment long term follow-up outcome showed that the occlusion maintained well except slight mandible forward growth.
[Conclusion] It is pertinent for orthodontists to apply early orthodontic treatment for Angle Class III children. Once the anterior cross-bite has been corrected, the mandibular growth may be guided into a more favorable pattern. And hopefully, the achieved occlusion could be maintained into adulthood.