下颌切牙神经解剖学观察

THE ANATOMIC STUDY OF THE MANDIBULAR INCISOR NERVE

目的 :研究国人切牙神经在下颌骨内的行程和分布 ,为临床自体骨移植的颏部取骨和种植体植入手术提供解剖学数据。方法 :磨开 1 3例 (2 6侧 )国人在体下颌骨标本 ,解剖 2 1侧脱钙下颌骨 ,显示下牙槽神经末段、切牙神经和颏神经全程 ,对切牙神经直接观测 ,另选 2 2侧下颌骨作切牙神经横断面观测。结果 :下牙槽神经前端分为切牙神经和颏神经 ,有牙颌切牙神经直径为 1 74± 0 2 5mm ,无牙颌切牙神经直径为 1 5 0± 0 2 2mm ;有牙颌切牙神经长度为 2 0 6 0± 2 6 2mm ,无牙颌切牙神经长度为 1 7 0 0± 2 85mm ;有牙颌的切牙神经 (在尖牙处 )至牙槽嵴顶的距离为 2 5 95± 4 5 0mm、无牙颌为 1 3 6 6±4 0 5mm ,至牙根尖为 1 1 5 6± 2 35mm ,至颌下缘为 9 6 2± 1 75mm ,至唇侧骨板的厚度为 5 1 9± 1 4 6mm ,至舌侧骨板的厚度为 4 6 6± 1 4 0mm ,切牙神经主要分布到下颌尖牙和切牙。结论 :切牙神经和颏神经均由下牙槽神经出发 ,颏神经向后上外 ,切牙神经向前呈弓状 ,位于下颌体前部的中下 1 / 3处 。

Objective:To study the course and distribution of the incisal nerve within the mandible.Methods:The incisor nerve,the anterior part of the inferior alveolar nerve and the mental nerve of 26 sides of Chinese mandibles and 21 sides of decalcified mandibles were dissected,and the position of the incisor nerve and its relation with the surrounding were investigated.The transverse section of incisal nerve of 22 sides of mandibles were also measured.Results:The diameter of the incisal nerve in mandible with complete dentition was 1 74±0 25,and 1 50±0 22 mm in edentulous mandible.The length of the incisor nerve in mandible with complete dentition was 20 60±2 62 mm,and 17 00±2 85 mm in edentulous mandibles.In the canine area the distance from the incisor nerve to alveolar ridge with complete dentition was 25 95±4 50 mm,and 13 66±4 05 mm in edentulous mandible,to root apex was 11 56±2 35 mm,to inferior border of mandible 9 62±1 75 mm;The thickness from the incisor nerve to labial surface of mandibles was 5 19±1 46 mm,to lingual surface of mandible was 4 66±1 40 mm.The incisor nerve mainly innervated the canine and incisor teeth of the mandible.Conclusion:The mental nerve bends backward,upward and outward.The incisor nerve extends forward assuming arcuate form and deviates to the lingual side at one third of middle and lower part of the mandible.