Iatrogenic injury to the inferior alveolar nerve: etiology, signs and symptoms, and observations on recovery.

The purpose of this prospective, non-randomised, descriptive study is to characterise the neurosensory deficit and associated neurogenic discomfort in 52 patients with iatrogenic injury to the inferior alveolar nerve (IAN). All patients were examined and followed up according to a protocol assessing tactile, thermal, and positional perception as well as two-point discrimination and pain. In 48 patients with IAN injuries of differing etiologies who did not undergo surgery, 32 patients with injury associated with third molar surgery exhibited significant spontaneous improvement of sensory function. Recovery improvement of sensory function was insignificant in the patients with other etiologies. In most patients the level of sensory perception was such that microsurgical repair was only occasionally indicated. Four patients had microsurgical repair; the outcome was favourable in three. IAN injuries associated with third molar surgery, other dento-alveolar surgery or implant surgery occur sufficiently often to render prevention a key issue.