Submandibular duct

{{Short description|Duct in the salivary gland}}

{{Infobox anatomy

| Name = Submandibular duct

| Latin = ductus submaxillaris

| Image = Gray1024.png

| Caption = Dissection, showing salivary glands of right side. (Labeled as "submaxillary duct", but is identified as "submandibular duct" in newer sources.)

| Image2 = Gray782.png

| Caption2 = Mandibular division of trifacial nerve, seen from the middle line. The small figure is an enlarged view of the otic ganglion. ("Wharton's duct" labeled in lower left.)

| System =

|Function=Drains saliva from submandibular gland to mouth|location=Below mouth|source=Submandibular gland|DrainsTo=Mouth}}

The submandibular duct (also Wharton's duct or historically submaxillary 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.

Structure

file:Sobo 1906 350.png

The submandibular duct arises from deep part of submandibular gland, a salivary gland. It begins by numerous branches from the superficial surface of the gland, and runs forward between the mylohyoid, hyoglossus, and genioglossus muscles. It then passes between the sublingual gland and the genioglossus and opens by a narrow opening on the summit of a small papilla (the "sublingual caruncle") at the side of the frenulum of the tongue. It lies superior to lingual and hypoglossal nerves.

= Variation =

The submandibular duct may be duplicated on one side or both sides, creating an accessory submandibular duct.{{Cite journal|last1=Pownell|first1=Patrick H.|last2=Brown|first2=Orval E.|last3=Pransky|first3=Seth M.|last4=Manning|first4=Scott C.|date=1 September 1992|title=Congenital abnormalities of the submandibular duct|url=https://dx.doi.org/10.1016/0165-5876%2892%2990142-C|journal=International Journal of Pediatric Otorhinolaryngology|language=en|volume=24|issue=2|pages=161–169|doi=10.1016/0165-5876(92)90142-C|pmid=1428595 |issn=0165-5876|url-access=subscription}}{{Cite journal|last1=Gadodia|first1=A.|last2=Seith|first2=A.|last3=Neyaz|first3=Z.|last4=Sharma|first4=R.|last5=Thakkar|first5=A.|date=September 2007|title=Magnetic resonance identification of an accessory submandibular duct and gland: an unusual variant|url=https://www.cambridge.org/core/journals/journal-of-laryngology-and-otology/article/abs/magnetic-resonance-identification-of-an-accessory-submandibular-duct-and-gland-an-unusual-variant/43A90D75F877E649D45E23D23182052A|journal=The Journal of Laryngology & Otology|language=en|volume=121|issue=9|pages=e18|doi=10.1017/S0022215107008602|pmid=17517164 |s2cid=23010849 |issn=1748-5460|url-access=subscription}} Rarely, it may not perforate into the mouth.

Function

The submandibular ducts drain saliva from the submandibular and sublingual glands to the sublingual caruncles in the floor of the mouth{{Citation |last1=Grewal |first1=Jeewanjot S. |title=Anatomy, Head and Neck, Submandibular Gland |date=2022 |url=http://www.ncbi.nlm.nih.gov/books/NBK542272/ |work=StatPearls |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=31194412 |access-date=2022-11-20 |last2=Jamal |first2=Zohaib |last3=Ryan |first3=Jesse}}

Clinical significance

= Sialolithiasis =

The submandibular duct may be affected by stones, known as sialolithiasis.{{Cite journal|last1=Raksin|first1=S Z|last2=Gould|first2=S M|last3=Williams|first3=A C|date=1975-02-01|title=Submandibular duct sialolith of unusual size and shape|url=https://europepmc.org/article/med/1054388|journal=Journal of Oral Surgery (American Dental Association|volume=33|issue=2|pages=142–145|issn=0022-3255|pmid=1054388}} These may grow large, requiring surgery to remove. Simple palpation may be used to identify the location of any stones before surgery.

= Imperforate =

Rarely, the submandibular duct may not perforate into the mouth. Surgery may be used to repair this birth defect.

= Drooling =

The exit of the submandibular gland into the mouth may be realigned in patients who drool.{{Cite journal|last1=Crysdale|first1=William S.|last2=White|first2=Ann|date=1989-07-01|title=Submandibular Duct Relocation for Drooling: A 10-Year Experience with 194 Patients|url=https://doi.org/10.1177/019459988910100114|journal=Otolaryngology–Head and Neck Surgery|language=en|volume=101|issue=1|pages=87–92|doi=10.1177/019459988910100114|pmid=2502766 |s2cid=1777182 |issn=0194-5998|url-access=subscription}} This redirects the exiting saliva away from the vestibule and the lips. This surgery has a fairly high success rate. Rarely, the submandibular gland may need to be removed on one or both sides.

History

The submandibular duct was initially described by the English anatomist Thomas Wharton ( 1614-73) and is sometimes referred to by his name.{{cite book | author=Wharton T | title=Adenographia: sive glandularum totius corporis descriptio | location=London | publisher=Wharton | year=1656 | pages=128–137}}

References

{{Gray's}}