Middle superior alveolar nerve

The middle superior alveolar nerve is a nerve that drops from the infraorbital portion of the maxillary nerve to supply the sinus mucosa, the roots of the maxillary premolars, and the mesiobuccal root of the first maxillary molar. It is not always present; and in the majority of cases it is non existent with the posterior superior alveolar nerve innervating the premolars and molars alone.