Twin-block矫治器前导下颌对髁突位置的影响:定量测量分析

Effect of Twin-block appliance on condylar process location during mandible forward positioning: Quantitative measurements

背景：利用Twin-block矫治器矫治下颌后缩时,下颌骨位置会发生显著的变化,这种变化会对颞颌关节产生怎样的影响,Twin-block矫治器能否促进髁突的生长是目前迫切需要研究的问题。目的：观察Twin-block矫治器前导下颌对髁突位置的影响。对象：选择解放军济南军区青岛第一疗养院口腔科收治的以下颌后缩为主的安氏Ⅱ类错患者20例,男13例,女7例,年龄9-13岁,平均10.8岁;均戴用Twin-block矫治器进行矫治。于Twin-block矫治器矫治前,矫治后1周,停戴后1周及1年时拍摄关节中位断层片,测量前上后关节间隙。结果与结论：所有患者在治疗后均达到中性咬合关系,在治疗前后均未出现弹响、疼痛等颞颌关节症状。治疗前与戴矫治器治疗1周后,髁突位置明显不同,其中关节前间隙距离减小,关节上间隙距离增大,关节后间隙加大（P〈0.05-0.01）,即髁突向前下移位;治疗结束后髁突位置与治疗前一致,关节前、上、后间隙均衡分布。提示Twin-block矫治器可通过生长改建恢复正常功能及协调的髁窝关系,但需要较长时间维持以促使试改建彻底完成。

BACKGROUND： Using Twin-block appliance to treat mandibular retrusion, the mandible position changes greatly. The influence of this change on temporomadibular joint and the effect of Twin-block appliance on condylar growth remain unclear. OBJECTIVE： To observe the effect of Twin-block appliance on condylar process location during mandible forward positioning. PARTICIPANTS： A total of 20 patients with mandible retraction （Angel Ⅱ） malocclusion were selected from Department of Stomatology, First Sanatorium of Qingdao, Jinan Military Area Command of Chinese PLA, comprising 13 males and 7 females, aged 10.8 years （range 9-13 years）. All patients were treated with Twin-block appliance. Four median joint pantomograms were taken before treatment, 1 week after treatment, 1 week and 1 year after treatment finish to measure the condylar process location. RESULTS AND CONCLUSION： In all cases, neutroclusion were obtained. No clicking, pain or other temporomadibular joint symptoms were observed. The condylar process position altered significantly. The anterior space distance was decreased, the superior space distance was increased, and posterior space was enlarged （P 0.05-0.01）, i.e. condylar process moved downward and forward. The condylar process position was consistent with preoperative, and joint superior, anterior and posterior space distributed balancedly. Twin-block appliance could restore normal and harmonious process-fossa relationship through growth remodeling, but maintenance is necessary till the remodeling accomplish.