Tuesday, November 22, 2011

Submandibular Ganglion

The submandibular ganglion is a group of parasympathetic nerve cell bodies which lies, together with several small secondary ganglia, in the floor of the mouth above the submandibular gland and below the lingual nerve, to which it connects via several ganglionic branches. The preganglionic parasympathetic fibers of the submandibular ganglion originate from the superior salivatory nucleus (located in the pontine tegmentum of the pons), run in the facial nerve (intermediate nerve), and leave the nerve together with the taste fibers in the chorda tympani. In the latter, the fibers reach the lingual nerve and extend in it to the floor of the mouth where they cross over into the ganglion. Postganglionic sympathetic fibers from the plexus of the external carotid artery reach the ganglion via the sympathetic branch given off by the plexus of the facial artery; they pass through the ganglion without synapsing. The postganglionic parasympathetic and sympathetic fibers pass partly in the glandular branches to the submandibular gland, partly in the lingual nerve to the sublingual gland and to the glands in the distal two-thirds of the tongue.