目的 分析患者的年龄、性别、身高和体质量等人口特征对下颌阻生第三磨牙拔除术难易程度的影响。方法 纳入需要拔除下颌阻生第三磨牙的病例。运用Spearman相关系数分析患者的年龄、性别、体质量、身高和体质量指数等与手术时间的相关性，并进一步选择显著相关的因素进行一元线性回归分析。结果 共纳入病例370例。患者年龄与手术时间有关(P<0.001)。一元线性回归分析结果显示患者年龄是手术时间延长的风险因素 (β=0.308，P<0.001)。结论 患者年龄是影响下颌阻生第三磨牙拔除难度的一个重要因素。

Objective To analyze the effect of patients′ age, sex, height, and body mass index (BMI) on the impacted mandibular third molar surgery. Methods Patients who needed third molar extractions were selected. The correlation of patients′ age, sex, weight, height, BMI and operation time was determined by Spearman′s rank correlation coefficient analysis. Statistically significant variables were selected for linear regression analysis. Results A total of 370 patients were enrolled. Only patients′ age showed a statistically significant correlation with operation time (P<0.001). Linear regression analysis indicated that patients′ age contribute 30.8% risk of increased operation time (β= 0.308, P<0.001). Conclusion Patients′ age is an important factor for affecting the operative difficulty of the impacted mandibular third molar.