成都地区青少年下颌牙弓后段可利用间隙的预测研究

目的　探讨成都地区青少年牙弓后段可利用间隙的增龄性变化,为临床应用全牙弓间隙分析提供依据。方法　将1999~2000年在原华西医科大学口腔医院正畸科就诊的11~20岁初诊患者,按纳入和排除标准筛选,共获得 526例,其中男232例,女294例。按颌骨的矢状向、垂直向异常分类,通过头影测量分析获得牙弓后段可利用间隙量。分析成都地区青少年牙弓后段可利用间隙增龄性变化规律,用多变量相关分析检测牙弓后段间隙量与年龄、性别、安氏错类型、垂直骨面型的相关性。结果　(1)下颌牙弓后段间隙量与年龄、安氏错类型相关。(2)男女性的下颌牙弓后段可利用间隙增龄性变化曲线有一定差异。(3)骨性Ⅲ类患者的牙弓后段可利用间隙增龄性变化量明显大于安氏Ⅰ、Ⅱ 类患者。结论　成都地区青少年的数值同国外数值差异较大,提示在进行全牙弓间隙分析时,应考虑种族的差异及错类型。

A Pilot Study on Changes of Posterior Available Spaces in Mandible Dentitions for Adolescents between the Ages of 11 and 20 Years in Chengdu Area

OBJECTIVE: The purpose of this study was to study the changes of available spaces of posterior arch segments in mandible dentitions (ASPAS) from ages of 11 to 20 years, which would provide information on normal growth and development of the dental arches in teenagers in Chengdu area. METHODS: The data were derived from systematically collected preorthodontic lateral cephalograms of 526 patients, including 232 males and 294 females from the Orthodontic Department of West China College of Stomatology, Sichuan University during the period of 1999-2000 (aged 11-20 years). The values of ANB angle, FH-MP, ASPAS were obtained using the cephalometric analysis. Afterwards, the growth changes of ASPAS from the subjects and their correlations with age, gender, angle malocclusion types and vertical skeletal patterns were analyzed. RESULTS: ASPAS was related to age and class II angle malocclusion. Though gender was not associated with ASPAS, significant differences in curves of ASPAS were found between males and females. The growth changes of ASPAS in the patients with skeletal Class III malocclusion were more obvious than in patients with Class I and II malocclusion. CONCLUSION: Our results reveal that significant differences were demonstrated in growth change values in posterior available spaces of patients with different races and angle malocclusion types.