SENSORY ABNORMALITIES ASSOCIATED WITH MANDIBULAR FRACTURES - INCIDENCE AND NATURAL-HISTORY

Purpose: The aims of this study were to determine the incidence of inf erior alveolar nerve (IAN) abnormalities in patients with mandibular f ractures and to document the natural history and spontaneous recovery rate in patients with a sensory disturbance. Patients and Methods: Thi s was a retrospective evaluation of patients (n = 150) with mandibular fractures at risk for IAN injury admitted to the Oral and Maxillofaci al Surgery Service between 1985 and 1995. The inclusion criteria were: 1) fractures between the mandibular and mental foramina, 2) availabil ity of the results of a post-injury, preoperative sensory examination, and 3) at least 1 year follow-up. Fracture characteristics, physical examination findings, hospital course, operative treatment, and follow -up were documented. Patient interviews were conducted to determine th e incidence of long-term sensory disturbance and associated morbidity. The results were evaluated with chi-square analysis. Results: Fifty-s ix percent of patients (84 of 150) had a post-injury/pretreatment IAN abnormality. Patients with sensory disturbance had a significantly hig her frequency of displaced fractures than those without sensory distur bance (P <.001). Sixteen of 24 patients (66.7%) with an abnormal post- injury/pretreatment sensory examination reported a permanent sensory d eficit (mean follow-up, 74.3 months); 55% of these patients complained of impairment. Conclusions: The incidence of postinjury IAN deficits in patients with mandibular fractures was greater than 50% and was rel ated to fracture displacement. One third of these patients regained no rmal sensation; the remaining two thirds reported a persistent sensory deficit. A significant number of these patients complained of discomf ort and impairment after a mean follow-up of greater than 6 years.