目的 精细解剖下颌角周围软组织结构及下颌神经管，为下颌角肥大整形术提供解剖学参考。 方法 20例大体标本，观察及测量面动静脉、面神经下颌缘支及咬肌区的血管和神经。据下颌骨表面骨性标志定位5条径线，测量该5条径线上下颌神经管在下颌骨中的位置。计算各软组织结构和下颌神经管的安全范围。 结果 面动脉距下颌角点为23.18～36.28 mm，距咬肌前缘为-9.51～9.27 mm。面静脉距离下颌角点为17.79～32.03 mm。面神经下颌缘支贴近下颌角部及下颌骨下缘走行，距离下颌角点为-8.57～10.70 mm，而咬肌前缘下颌缘支距下颌骨下缘为-8.83～11.06 mm。咬肌的血供主要有面动脉咬肌支、颈外动脉咬肌支、上颌动脉咬肌支及面横动脉咬肌支这四大来源。咬肌神经多与咬肌动脉伴行进入咬肌。下颌神经管在5个截面中距离下颌骨外侧点分别大于10.50 mm、14.72 mm、15.60 mm、8.53 mm、6.74 mm。 结论 在剥离下颌角区软组织时，注意对咬肌前缘面动脉、面神经下颌缘支及下颌角点附近面神经下颌缘支的保护。去除咬肌的最佳层次为咬肌深层中份最厚点及中下份。而在截骨或劈骨时，根据下颌神经管的安全范围，可在下颌骨颊侧骨板快速画出一条指导性的安全线。

Objective To dissect soft tissue structure around the mandibular angle and the mandibular nerve canal accurately, as to provide anatomical reference for the mandibular angle hypertrophy operation. Methods Twenty formalin-fixed adult head-and-neck specimens were observed and measured for facial arteries and veins, the marginal mandibular branch of the facial nerves, and the vessels and nerves of masseter muscle. Five lines positioned according to the characteristic structures of the mandible were used for the measurement of mandibular nerve canal. The safety range of the soft tissue structure and the mandibular nerve canal，external carotid artery, maxillary artery, and transverse facial artery were calculated. Results The distance between the facial artery and the mandibular angle is 23.18-36.28 mm. Facial artery to the anterior margin of masseter muscle is -9.51-9.27 mm. Separation between the facial vein and the mandibular angle is 17.79-32.03 mm. The marginal mandibular branch of the facial nerve is close to the mandibular angle and the lower edge of the mandible, measurements showed a distance of -8.57-10.70 mm towards mandibular angle. At anterior masseter muscle, separation between mandibular branches and the lower edge of the mandible is-8.83-11.06 mm. The four major sources of masseter arteries are the masseter branch of the facial artery, external carotid artery, maxillary artery, and transverse facial artery. The masseter nerve entered the masseter muscle alongside with the masseter artery. In the five cross sections, the disctance from mandibular nerve canal to the lateral mandibular point is more than 10.50 mm, 14.72 mm, 15.60 mm,8.53 mm and 6.74 mm, respectively. Conclusion Attention should be paid, when undermining soft tissue in the mandibular angle, three main structures specifically the facial artery and the marginal mandibular branch of facial nerve located at the anterior aspect of mandibular muscle, and the mandibular marginal branch of the facial nerve located at the mandibular angle are prerogative. Layers removed from the masseter muscle are best done at the thickest region of the middle inferior aspect. A guide safety line can be drawn quickly during osteotomy on the buccal bone palate of the mandible based on the safety range of mandibular nerve canal.