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目的:通过显微CT测量182颗恒牙邻面牙釉质厚度，以期为正畸临床邻面去釉提供参考。方法:2016年5月至2018年2月于首都医科大学口腔医学院口腔颌面外科门诊收集筛选182颗离体恒牙[来源于正畸减数和重度牙周炎患者,牙齿提供者均为北京市居民，汉族，年龄（39.5±10.6）岁，90%的牙齿来源于50岁以下的患者]，并根据牙位进行分类，用流体树脂于牙齿近远中邻面接触区做标记后进行小动物计算机体层显像扫描，对影像资料进行三维重建及测量，分析各牙位牙齿近中和远中邻面牙釉质厚度、近中和远中邻面接触区至n 面距离、近中和远中邻面接触区至釉质牙骨质界距离、牙冠近远中向宽度。n 结果:邻面牙釉质厚度从前牙区[（0.63±0.16） mm]到磨牙区[（1.46±0.25）mm]逐渐增厚。上颌左侧第二磨牙远中邻面至右侧第二磨牙远中邻面的牙釉质厚度均值之和为31.60 mm，下颌左侧第二磨牙远中邻面至右侧第二磨牙远中邻面的牙釉质厚度均值之和为29.68 mm。前牙区邻面接触区垂直向位置靠近牙冠切1/3，磨牙区邻面接触区更接近牙冠中1/3。近中和远中邻面牙釉质厚度与牙冠近远中向宽度均呈正相关关系（n P均<0.05）。n 结论:本组离体牙结果显示，切牙区近远中邻面牙釉质厚度较小，磨牙区较大；临床应在前牙区靠近切端、在后牙区靠近龈方进行邻面去釉。“,”Objective:To measure the proximal enamel thickness (PET) at the mesial and distal contact areas of the permanent teeth and to provide a reference for interproximal enamel reduction (IPR).Methods:From May 2016 to February 2018, 182 isolated permanent teeth were collected and screened from patients who underwent extraction at Department of Oral and Maxillofacial Surgery, Capital Medical University School of Stomatology. These teeth were extracted for orthodontic purpose or due to severe periodontitis. The patients having teeth extracted were all Beijing residents, Han nationality, and aged (39.5±10.6) years. Ninety percent of the teeth came from patients under 50 years old. These teeth were classified according to different tooth type. The mesial and distal contact areas of these teeth were marked with fluid resin. The isolated teeth were scanned using micro-CT and the enamel thickness was measured and analyzed. The parameters measured included mesial PET (PETm), distal PET (PETd), the distance from mesial contact area to occlusal plane (CAm-OP), the distance from distal contact area to occlusal plane (CAd-OP), the distance from mesial contact area to the cementoenamel junction (CAm-CEJ), the distance from distal contact area to cementoenamel junction (CAd-CEJ) and tooth width (TWmd).Results:The PET gradually increased from the anterior tooth area [(0.63±0.16) mm] to the molar area [(1.46±0.25) mm]. The sum of the PET from the second molar to the contralateral second molar in the maxillary dentition was 31.60 mm, and that of the PET from the second molar to the contralateral second molar in the mandibular dentition was 29.68 mm. The contact areas were located on the occlusal third of the proximal walls of anterior teeth and the middle third of the proximal walls of posterior teeth. The PET were positively correlated with the tooth width between the mesial and distal contact areas (n P<0.05).n Conclusions:The PET was thinner in the incisor area and thicker in the molar area. IPR should be carried out close to the occlusal side of the proximal walls in anterior teeth and the cementoenamel junction side of the proximal walls in posterior teeth.