Inferior alveolar nerve canal position: a clinical and radiographic study.

PURPOSE: To document a clinically relevant position of the inferior alveolar nerve (IAN) in dentate patients and identify patient factors associated with IAN position.

MATERIALS AND METHODS: The investigators used a cross-sectional study design and a study sample of subjects who had a radiographically identifiable IAN canal and at least 1 mandibular first molar was enrolled. Predictor variables were age, gender, and race. Outcome variables were the linear distances between the buccal aspect of the IAN canal and the outer buccal cortical margin of the mandible, and the superior aspect of the IAN canal and the alveolar crest. Appropriate uni-, bi-, and multivariate statistics were computed.

RESULTS: The study sample was composed of 50 patients with a mean age of 42 years, 42.0% were male, and 73.2% were white. On average, the buccal aspect of the canal was 4.9 mm from the buccal cortical margin of the mandible. The superior aspect of the IAN canal was 17.4 mm inferior from the alveolar crest. Age and race were statistically associated with IAN position relative to the buccal cortical mandibular margin (P<.05). None of the demographic variables were associated with vertical position.

CONCLUSIONS: The IAN canal was 4.9 mm and 17.4 mm from the buccal and superior cortical surfaces of the mandible, respectively. The bucco-lingual IAN canal position was associated with age and race. Older patients and white patients, on average, have less distance between the buccal aspect of the canal and the buccal mandibular border. To minimize the risk of IAN injury, these variables should be considered when planning mandibular osteotomies or using monocortical plates.