After an inferior alveolar nerve block, paralysis of the eyelid, upper lip, and lower lip indicates that the local anesthetic was deposited into which location?

When a local anesthetic is inadvertently deposited into the parotid gland during an inferior alveolar nerve block, it can lead to temporary paralysis of the facial muscles supplied by the facial nerve, which runs closely with the inferior alveolar nerve. This leads to the paralysis of the eyelid, upper lip, and lower lip because the facial nerve innervates these areas.

In contrast, locations like the maxillary sinus, submandibular gland, and mental foramen do not typically produce this specific pattern of paralysis. The maxillary sinus is involved in procedures related to the maxillary teeth and does not influence the facial nerve, while the submandibular gland is associated with the lingual and hypoglossal nerves, not the facial nerve. Furthermore, the mental foramen is primarily where the mental nerve exits and would not affect the eyelid or upper lip in the way described. Thus, the correct identification of the parotid gland as the site where the anesthetic was deposited explains the resulting paralysis of facial regions observed after the block.