HISTOPATHOLOGIC FINDINGS OF THE DEGENERATED INFERIOR ALVEOLAR NERVES RESECTED DUE TO REFRACTORY TRIGEMINAL NEURALGIA

ABSTRACT

This is to report the histo-pathologic findings of the degenerated inferior alveolar nerves(IAN) causing uncontrollable neuralgia persisted for over 3 years. The patients had sufferred from frequent attack of unbearable pain along the mandibular branches of the Vth nerve. The pain arised spontaneously 5-10 times a day and lasted for 2-5 minutes. The medications including Tegretol were neither so effective to alleviate the pain level, nor enough to keep free from pain all days. The peripheral neurectomies were preceded by diagnostic nerve block, and partial resection of the IAN in the mandibular canals were approached by sagittal split osteomy of the ramus. The histopathologic findings of the resected IAN were as follows ; 1. Special staining with Luxol Fast Blue (LFB) and Masson Trichrome (MT) disclosed marked degeneration of the axons, decreased in number and fibrosis between the nerve fibers. 2. EM study revealed destruction of myelin continuity surrounding axons, degeneration of Schwann cell and endoneureal sheath, and coarse collagen between the destructed axons. 3. The 3 of 6 patients presented again with recurred pain in 2-3 years after the peripheral neurectomies. Excisional biopsy of the retromolarpterygomandibular softtissues disclosed the collateralization neuropathy beside the long-buccal nerves and their neuromatous findings.