Transient facial paralysis may occur if anesthetic is deposited into the parotid gland during which injection?

• A. Inferior alveolar nerve block
• B. Posterior superior alveolar injection
• C. Mental nerve block
• D. Buccal nerve block

Answer: (A)

Transient facial paralysis occurs when anesthesia reaches the parotid gland, which houses facial nerve branches inside its tissue. The inferior alveolar nerve block is given in the pterygomandibular area near the mandibular foramen, and if the needle or anesthetic thread goes too high or deep into the gland, it can bathe the facial nerve fibers in the parotid. Because the facial nerve (even its motor branches) runs through or near the parotid, this diffusion temporarily blocks those fibers, causing short‑lived facial weakness on the same side as the injection.

The other injections target areas away from the parotid region: the posterior superior alveolar block is in the infratemporal area for maxillary nerves, the mental nerve block is at the mental foramen of the mandible, and the buccal nerve block sits along the cheek near the buccinator. These routes are not typically through the parotid gland, so they are less likely to produce transient facial paralysis.