The submandibular ganglion is a parasympathetic ganglion situated on the floor of the mouth, on the superficial surface of the hyoglossus muscle. It lies between the lingual nerve and the deep part of the submandibular gland and is suspended by two roots from the lingual nerve. The submandibular ganglion is responsible for the innervation of the submandibular and sublingual glands. Preganglionic parasympathetic fibers originate from the superior salivatory nucleus in the brain stem. These fibers travel with the nervus intermedius of the facial nerve into the internal acoustic meatus and exit the skull through the petrotympanic fissure as the chorda tympani nerve. The chorda tympani nerve then joins the lingual nerve.