The anatomic basis of lingual nerve trauma associated with inferior alveolar block injections

Purpose This study describes the anatomic variability in the position of the lingual nerve in the pterygomandibular space, the location of the inferior alveolar nerve block injection. Materials and Methods Simulated standard landmark-based inferior alveolar nerve blocks were administered to 44 fixed sagitally bisected cadaver heads. Measurements were made of the diameter of the nerves and distances between the needle and selected anatomic landmarks and the nerves. Results Of 44 simulated injections, 42 (95.5%) passed lateral to the lingual nerve, 7 (16%) passed within 0.1 mm of the nerve, and 2 (4.5%) penetrated the nerve. The position of the lingual nerve relative to bony landmarks within the interpterygoid fascia was highly variable. Conclusion Variation in the position of the lingual nerve is an important contributor to lingual nerve trauma during inferior alveolar block injections. This factor should be an important part of preoperative informed consent.