下颌阻生智齿相关第二磨牙牙根外吸收：曲面断层片与CBCT对比研究

目的 比较曲面断层片和CBCT在诊断下颌阻生智齿相关第二磨牙牙根外吸收的差异。方法 回顾性分析2019年1月—2020年12月于南京医科大学附属口腔医院就诊的832例(1 074颗)近中/水平下颌阻生智齿病例，分别应用曲面断层片和CBCT评估下颌第二磨牙远中牙根外吸收发生率，并分析曲面断层片诊断错误的相关因素。结果 以CBCT影像学结果判定为标准，下颌智齿相关第二磨牙牙根外吸收的发生率为33.15%(356/1 074),曲面断层片诊断正确率为66.39%。经多因素Logistic回归分析发现：中低位、Ⅲ类阻生智齿，下颌阻生智齿与第二磨牙牙根重叠，下颌阻生智齿与第二磨牙牙根接触是导致曲面断层片诊断错误的危险因素(P<0.05)。结论 曲面断层片诊断下颌阻生智齿相关第二磨牙牙根外吸收正确性较低，推荐选用CBCT检测。

Comparison of panoramic radiography and cone-beam computed tomography images for detecting external root resorption of mandibular second molar associated with third molar impaction

Objective To compare the diagnostic performance between panoramic radiography(PR)and cone beam computed tomography(CBCT)in the assessment of external root resorption(ERR)of mandibular second molars associated with impacted third molars. Methods A total number of 832 patients with 1 074 mesially and horizontally impacted mandibular third molars treated at our institution from January 2019 to December 2020 were retrospectively analyzed. Presence of ERR on the adjacent second molar was investigated with PR and CBCT. Factors affecting the diagnostic accuracy of PR were determined. Results The overall incidence of ERR in second molars was 33.15%(356/1 074)as detected by CBCT images. The accuracy of PR was 66.39%. Multivariate Logistic regression analyses further revealed that middle and Class Ⅲ impaction, crown contact or overlap with the root of adjacent tooth were risk factors for inaccurate diagnosis of PR(P<0.05). Conclusion The accuracy of detection on ERR of mandibular second molar associated with impacted third molar using panoramic radiography is lower. CBCT is recommended for this clinical scenario.