应用曲面断层片定位埋伏阻生上颌尖牙的可靠性研究

Determining position of an impacted maxillary canine based on panoramic radiograph

目的探讨应用全口曲面断层片定位埋伏阻生上颌尖牙的可靠性和临床应用价值。方法依据纳入标准选择患者45例,每一患者均拍摄全口曲面断层片,测量埋伏尖牙、同侧中切牙以及对侧正常尖牙的最大的近远中径。同时在垂直方向上以相邻的完全萌出的中切牙为标准,分成牙冠、根中和根尖3部分。结果经过SPSS统计软件处理。结果如果埋伏尖牙位于邻牙的牙冠和根中部,当尖牙和同侧中切牙近远中径之比(CⅠ值)等于或大于1.10时表明它们全部位于腭侧。但是在根尖部仅用此方法不能辨别其唇腭侧位置。结论通过限定埋伏阻生尖牙在垂直方向上的位置,利用曲面断层片诊断埋伏尖牙的唇腭侧位置是可信的。

Objective To develop a reliable method for determining the position of an impacted maxillary canine in the panoramic radiograph. Methods In panoramic readiographs of 45 patients with impacted canines, the maximal mesiodistal middle diameters of impacted canine, homolateral and contralateral incisors were measured. All data were analyzed using SPSS software. Results When the impacted canine in radiograph is shown vertieally at the level of the coronary zone and middle part of root of the adjacent incisors, and the ratio of mesiodistal middle diameters of the canine and the homolateral incisor is equal to or greater than 1.10, it lies at palatal side;when, however, at the level of apical zone of adjacent incisors, its labiopalatine position cannot be discerned.. Conclusions It is reliable to determine the labiopalatine position of impacted canine by locating it vertically in the panoramic radiograph.