The paired sublingual glands are major
salivary glands in the
mouth
In animal anatomy, the mouth, also known as the oral cavity, or in Latin cavum oris, is the opening through which many animals take in food and issue vocal sounds. It is also the cavity lying at the upper end of the alimentary canal, bounded on ...
. They are the smallest, most diffuse, and the only unencapsulated major salivary glands. They provide only 3-5% of the total salivary volume.
There are also two other types of
salivary glands; they are
submandibular and
parotid glands.
Structure
They lie anterior and superior to the
submandibular gland
The paired submandibular glands (historically known as submaxillary glands) are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimul ...
and inferior and lateral to the
tongue
The tongue is a muscular organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste ...
, as well as beneath the
mucous membrane of the floor of the mouth. They are bounded laterally by the bone of the mandible and inferolaterally by the
mylohyoid muscle
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 flo ...
. The glands can be felt behind each mandibular canine. Placing one index finger within the mouth and the fingertips of the opposite hand outside it, the compressed gland is manually palpated between the inner and outer fingers.
[Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, p. 156]
The sublingual glands are drained by 8-20 excretory ducts called the ducts of Rivinus.
[Ten Cate's Oral Histology, Nanci, Elsevier, 2013, page 255] The largest of all, the
sublingual duct (of Bartholin) joins the submandibular duct to drain through the
sublingual caruncle. The sublingual caruncle is a small papilla near the midline of the floor of the mouth on each side of the lingual frenum.
Most of the remaining small sublingual ducts (of Rivinus) open separate into the mouth on an elevated crest of mucous membrane, the
plica sublingualis (aka ''sublingual fold''), formed by the gland and located on either side of the
frenulum linguae.
270px, Drawing of an open mouth showing the frenulum linguae & surrounding structures
Microanatomy
The sublingual gland consists mostly of mucous acini capped with
serous demilunes
Serous demilunes, also known as Crescents of Giannuzzi or Demilunes of Heidenhain, are cellular formations in the shape of a half-moon (hence the name "demilune") on some salivary glands.
Serous demilunes are the serous cells at the distal end of ...
and is therefore categorized as a mixed mucous gland with a mucous product predominating.
Striated
Striations means a series of ridges, furrows or linear marks, and is used in several ways:
* Glacial striation
* Striation (fatigue), in material
* Striation (geology), a ''striation'' as a result of a geological fault
* Striation Valley, in ...
and
intercalated ducts are also present.
Blood supply
The gland receives its blood supply from the sublingual and submental arteries.
Lymph from the sublingual salivary gland drains into the
submandibular lymph nodes.
Nerve supply
The
chorda tympani nerve (from the
facial nerve via the
submandibular ganglion) is
secretomotor and provides parasympathetic supply to the sublingual glands. The path of the nerve is as follows: junction between
pons and
medulla, through
internal acoustic meatus and
facial canal to
chorda tympani, through middle ear cavity, out petrotympanic fissure to join the
lingual nerve, travels with lingual nerve to synapse at the
submandibular ganglion, then
postganglionic fibers travels to the sublingual gland.
Development
The sublingual salivary glands appear in the eighth week of prenatal development, two weeks later than the other two major salivary glands. They develop from
epithelial
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellu ...
buds in the sulcus surrounding the sublingual folds on the floor of the mouth, lateral to the developing submandibular gland. These buds branch and form into cords that canalize to form the sublingual ducts associated with the gland. The rounded terminal ends of the cords form
acini
An acinus (; plural, acini; adjective, acinar or acinous) refers to any cluster of cells that resembles a many-lobed "berry," such as a raspberry (''acinus'' is Latin for "berry"). The berry-shaped termination of an exocrine gland, where the s ...
.
[Illustrated Dental Embryology, Histology, and Anatomy, Bath-Balogh and Fehrenbach, Elsevier, 2011, page 136-137]
Clinical significance
Ranula
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 caus ...
s are the most common pathologic lesion associated with the sublingual glands.
Additional images
Gray1024.png , Imaging showing the sublingual glands and surrounding structures.
Image:Gray177.png, Mandible. Inner surface. Side view.
File:Slide1vv.JPG, Sublingual gland
File:Slide4ww.JPG, Sublingual gland
File:Slide14ww.JPG, Sublingual gland
References
External links
* - "Oral Cavity: Glands"
* ()
*
Salivary gland infectionsfrom
Medline Plus
MedlinePlus is an online information service produced by the United States National Library of Medicine. The service provides curated consumer health information in English and Spanish with select content in additional languages.
The site brings t ...
Salivary gland cancerfrom
American Cancer Society
The American Cancer Society (ACS) is a nationwide voluntary health organization dedicated to eliminating cancer. Established in 1913, the society is organized into six geographical regions of both medical and lay volunteers operating in more than ...
{{Authority control
Glands of mouth