The salivary glands in many vertebrates including mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands, as well as hundreds of minor salivary glands. Salivary glands can be classified as serous, mucous, or seromucous (mixed).
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerve typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI and anterior to cranial nerve VIII.
Articles related to anatomy include:
The parotid gland is a major salivary gland in many animals. In humans, the two parotid glands are present on either side of the mouth and in front of both ears. They are the largest of the salivary glands. Each parotid is wrapped around the mandibular ramus, and secretes serous saliva through the parotid duct into the mouth, to facilitate mastication and swallowing and to begin the digestion of starches. There are also two other types of salivary glands; they are submandibular and sublingual glands. Sometimes accessory parotid glands are found close to the main parotid glands.
The paired submandibular glands are major salivary glands located beneath the floor of the mouth. In adult humans, they each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as parotid gland secretion rises to 50%. The average length of the normal adult human submandibular salivary gland is approximately 27 mm, while the average width is approximately 14.3 mm.
Chorda tympani is a branch of the facial nerve that carries gustatory (taste) sensory innervation from the front of the tongue and parasympathetic (secretomotor) innervation to the submandibular and sublingual salivary glands.
The mylohyoid muscle or diaphragma oris is a paired muscle of the neck. It runs from the mandible to the hyoid bone, forming the floor of the oral cavity of the mouth. It is named after its two attachments near the molar teeth. It forms the floor of the submental triangle. It elevates the hyoid bone and the tongue, important during swallowing and speaking.
The hyoglossus is a thin and quadrilateral extrinsic muscle of the tongue. It originates from the hyoid bone; it inserts onto the side of the tongue. It is innervated by the hypoglossal nerve. It acts to depress and retract the tongue.
A ranula is a mucus extravasation cyst involving a sublingual gland and is a type of mucocele found on the floor of the mouth. Ranulae present as a swelling of connective tissue consisting of collected mucin from a ruptured salivary gland caused by local trauma. If small and asymptomatic further treatment may not be needed, otherwise minor oral surgery may be indicated.
The lingual nerve carries sensory innervation from the anterior two-thirds of the tongue. It contains fibres from both the mandibular division of the trigeminal nerve (CN V3) and from the facial nerve (CN VII). The fibres from the trigeminal nerve are for touch, pain and temperature (general sensation), and the ones from the facial nerve are for taste (special sensation).
The submandibular duct is one of the salivary excretory ducts. It is about 5 cm long, and its wall is much thinner than that of the parotid duct. It drains saliva from each bilateral submandibular gland and sublingual gland to the sublingual caruncle in the floor of the mouth.
The submandibular ganglion is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck..
Sialadenitis (sialoadenitis) is inflammation of salivary glands, usually the major ones, the most common being the parotid gland, followed by submandibular and sublingual glands. It should not be confused with sialadenosis (sialosis) which is a non-inflammatory enlargement of the major salivary glands.
The intermediate nerve, nervus intermedius, nerve of Wrisberg or Glossopalatine nerve is the part of the facial nerve located between the motor component of the facial nerve and the vestibulocochlear nerve. It contains the sensory and parasympathetic fibers of the facial nerve. Upon reaching the facial canal, it joins with the motor root of the facial nerve at the geniculate ganglion. Alex Alfieri postulates that the intermediate nerve should be considered as a separate cranial nerve and not a part of the facial nerve.
The excretory ducts of the sublingual gland are from eight to twenty in number. Of the smaller sublingual ducts, some join the submandibular duct; others open separately into the mouth, on the elevated crest of mucous membrane, caused by the projection of the gland, on either side of the frenulum linguae. One or more join to form the major sublingual duct, which opens into the submandibular duct.
The salivatory nuclei are two parasympathetic general visceral efferent cranial nerve nuclei - the superior salivatory nucleus and the inferior salivatory nucleus - that innervate the salivary glands. Both are located in the pontine tegmentum of the brainstem.
The following outline is provided as an overview of and topical guide to human anatomy:
The sublingual space is a fascial space of the head and neck. It is a potential space located below the mouth and above the mylohyoid muscle, and is part of the suprahyoid group of fascial spaces.
Lingual papillae are small structures on the upper surface of the tongue that give it its characteristic rough texture. The four types of papillae on the human tongue have different structures and are accordingly classified as circumvallate, fungiform, filiform, and foliate. All except the filiform papillae are associated with taste buds.
Salivary gland diseases (SGDs) are multiple and varied in cause. There are three paired major salivary glands in humans: the parotid glands, the submandibular glands, and the sublingual glands. There are also about 800–1,000 minor salivary glands in the mucosa of the mouth. The parotid glands are in front of the ears, one on side, and secrete mostly serous saliva, via the parotid ducts, into the mouth, usually opening roughly opposite the second upper molars. The submandibular gland is medial to the angle of the mandible, and it drains its mixture of serous and mucous saliva via the submandibular duct into the mouth, usually opening in a punctum in the floor of mouth. The sublingual gland is below the tongue, on the floor of the mouth; it drains its mostly mucous saliva into the mouth via about 8–20 ducts, which open along the plica sublingualis, a fold of tissue under the tongue.
