Abstract: Objective: To evaluation and assessment the relevant multi-factors on the mandibular third molar extraction. Methods: A total of 511 patients with unilateral mandibular third molar removed by the same medical group from April 1, 2016 to October 1, 2016 were included. The demographic, anatomical features, and operation modes of patients were recorded. The multiple linear regression model was established by using the operation time as the dependent variable, and the related multi-factors affecting the operation of mandibular third molar extraction were evaluated quantitatively. Results: As the multiple linear regression model showed, age, gender, body mass index, preoperative interincisor distance, the number and morphology of the root revealed by radiological examination had no correlation with operation time, which represents the complexity of the operation. But coupled with the higher modified Pederson score of impact type, the complexity of surgery, the high incidence of root fracture in operation were all postive correlated with operation time. Conclusion: The modified Pederson score can accurately evaluate the complexity of mandibular third molar extraction. And clinicians should pay more attention to those paitents with the higher Pederson score, which were always accompanied with more surgery complications and higher root fracture incidence in operation .

Key words:  mandibular third molar, extraction mode, operative time, multiple linear regression

摘要： 目的：分析评价下颌阻生第三磨牙拔除术的相关影响因素。方法：选择2016?鄄04?鄄01—2016?鄄10?鄄01期间，由同一医疗组拔除的单侧下颌阻生第三磨牙的患者511例，分别记录每位患者的人口学特征、局部解剖学特征、手术方式等相关因素。以手术时间为因变量，建立多重线性回归模型，定量评价影响下颌阻生第三磨牙拔除手术的多种相关因素。结果：多重线性回归模型显示，年龄、性别、身高体重指数、术前开口度、影像学检查显示的牙根数目与形态，均与手术时间无相关性;而反映阻生类型的改良Pederson评分越高，所需手术方式越复杂，术中断根发生率越高，手术时间相应增加。结论：改良Pederson评分、手术方式、术中断根是影响手术难度的独立危险因素，临床医生在评估预测手术难度时需提高重视。

关键词: 下颌第三磨牙, 拔除难度, 手术时间, 多重线性回归

CLC Number: 

• R782.11