Loescher A R, Robinson P P
Department of Oral and Maxillofacial Surgery, University of Sheffield School of Clinical Dentistry, Charles Clifford Dental Hospital, U.K.
Brain Res. 1990 Dec 17;536(1-2):257-60. doi: 10.1016/0006-8993(90)90033-8.
Previous electrophysiological investigations have shown that reinnervated periodontal mechanoreceptors, 12 weeks after crushing or sectioning the inferior alveolar nerve, have altered discharge properties. These alterations may have resulted from the regeneration of axons along inappropriate endoneurial sheaths distal to the injury site and this possibility was investigated by comparing the properties of reinnervated mechanoreceptors after nerve crush with those after nerve freeze (after which endoneurial sheath guidance is not lost). In 4 cats, 67 periodontal mechanosensitive units supplying the lower canine were examined 12 weeks after freezing the inferior alveolar nerve. When compared with controls, they were found to have significantly smaller arcs of sensitivity, raised force thresholds, lower discharge frequencies and reduced dynamic indices. These characteristics were, however, similar to those of units examined after nerve crush. These results suggest that the alterations in receptor properties after nerve injury cannot be attributed to a mismatch between the regenerating axons and their receptors.
以往的电生理研究表明，在切断或横断下牙槽神经12周后，重新支配的牙周机械感受器的放电特性发生了改变。这些改变可能是由于轴突沿着损伤部位远端不适当的神经内膜鞘再生所致，通过比较神经挤压后和神经冷冻后（冷冻后神经内膜鞘导向不失）重新支配的机械感受器的特性，对这种可能性进行了研究。在4只猫中，在冷冻下牙槽神经12周后，检查了67个供应下犬齿的牙周机械敏感单位。与对照组相比，发现它们的敏感弧明显更小、力阈值升高、放电频率降低和动态指数降低。然而，这些特征与神经挤压后检查的单位相似。这些结果表明，神经损伤后感受器特性的改变不能归因于再生轴突与其感受器之间的不匹配。
