颌面部高速投射物伤致下牙槽神经间接损伤的超微结构研究

An Ultrastructural Study on Indirect Injury of Inferior Alveolar Nerve Caused by High Speed Projectile in Maxillofacial Region

目的:研究颌面部高速投射物伤导致的下牙槽神经间接损伤的特点。方法:18只实验犬随机均分为6组,以直径6.0 mm、质量0.88 g的高速投射物(不锈钢珠)致伤犬右下颌骨体部,但不直接伤及下牙槽神经;分别于伤后6 h、24 h、3 d、7 d、2 w及4 w处死实验犬,用透射电镜观察伤侧下牙槽神经距离弹着点0.5 cm处、2.0 cm处及对侧下牙槽神经的超微结构变化。结果:伤侧下牙槽神经距弹着点0.5 cm处损伤较重,且超微结构变化出现较早;2.0 cm处损伤相对较轻,且超微结构变化出现较迟;对侧下牙槽神经仅有轻度一过性损伤。结论:颌面部高速投射物伤导致的下牙槽神经间接损伤均有损伤范围较广,损伤程度随着距离的增加而迅速递减,损伤具有不均匀性等特点。

Objective： To investigate the characteristics of indirect injury of inferior alveolar nerve caused by high speed projectile in maxillofacial region. Methods： 18 dogs were divided equally into six groups with random allocation, then a high speed projectile （ a stainless steel bead, φ6.0mm, 0.88g） was shot at the right mandible body of each dog, but the inferior alveolar nerve was not injured directly; afterwards the experimental dogs were killed 6h, 24h, 3d, 7d, 2w and 4w later, respectively; then the uhrastructural changes of inferior alveolar nerve were observed through transmission electron microscope（TEM）. Results： In the inferior alveolar nerve of experimental side, the spot 0.5cm away from the wound was injured swiftly and seriously, the spot 2.0cm away from the wound was injured less seriously, yet the inferior alveolar nerve of the opposite side was injured slightly and temporarily. Conclusion： There are several characteristics in the indirect injury of inferior alveolar nerve caused by high speed projectile in maxillofacial region ： relatively extensive range ; traumatic degree decreases progressively and sharply with the distance to the increasing wound tract; nonuniformity, etc.