View source for Soft palate

{{Short description|Flexible part of maxilla}}
{{Infobox anatomy
| Name        = Soft palate
| Latin       = palatum molle, velum palatinum
| Image       = Tonsils diagram.jpg
| Caption     =
| Image2      = Blausen 0872 UpperRespiratorySystem.png
| Caption2    = Upper respiratory system, with ''soft palate'' labeled near center.
| Precursor   =
| System      =
| Artery      = [[Lesser palatine arteries]], [[ascending palatine artery]]
| Vein        =
| Nerve       = [[Pharyngeal branch of vagus nerve]], [[medial pterygoid nerve]], [[lesser palatine nerves]], [[glossopharyngeal nerve]]<ref>{{cite book |last=Walker |first=H. Kenneth |chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK386/ |title=Clinical Methods: The History, Physical, and Laboratory Examinations |access-date=2017-09-12 |url-status=live |archive-url=https://web.archive.org/web/20180504184506/https://www.ncbi.nlm.nih.gov/books/NBK386/ |archive-date=2018-05-04 |isbn=9780409900774 |chapter=Cranial Nerves IX and X: The Glossopharyngeal and Vagus Nerves |publisher=Butterworths |year=1990 |pages=327–328 |editor1-last=Walker |editor1-first=H. Kenneth |editor2-last=Hall |editor2-first=W. Dallas |editor3-last=Hurst |editor3-first=J. Willis |edition=3rd}}</ref>
| Lymph       =
}}
The '''soft palate''' (also known as the '''velum''', '''palatal velum''', or '''muscular palate''') is, in [[mammal]]s, the soft [[biological tissue|tissue]] constituting the back of the roof of the [[mouth]].  The soft palate is part of the [[palate]] of the mouth; the other part is the [[hard palate]]. The soft palate is distinguished from the hard palate at the front of the mouth in that it does not contain [[bone]].

==Structure==

===Muscles===
[[File:Gray1028.png|thumbnail|Dissection of the muscles of the palate from behind.]]

The five muscles of the soft palate play important roles in swallowing and breathing. The muscles are: 
# [[Tensor veli palatini]], which is involved in [[swallowing]]
# [[Palatoglossus]], involved in [[swallowing]]
# [[Palatopharyngeus]], involved in [[breathing]]
# [[Levator veli palatini]], involved in [[swallowing]]
# [[Musculus uvulae]], which moves the [[palatine uvula|uvula]]

These muscles are innervated by the [[pharyngeal plexus]] via the [[vagus nerve]], with the exception of the [[tensor veli palatini]]. The tensor veli palatini is innervated by the [[mandibular division of the trigeminal nerve]] (V<sub>3</sub>).<ref name=GRAYS2005>{{cite book|last=Drake|first=Richard L.|title=Gray's anatomy for students|year=2005|publisher=Elsevier/Churchill Livingstone|location=Philadelphia|isbn=978-0-8089-2306-0|author2=Vogl, Wayne |author3=Tibbitts, Adam W.M. Mitchell  |author4=illustrations by Richard |author5= Richardson, Paul |page=1000}}</ref>

==Function==
The soft palate is moveable, consisting of [[muscle]] fibers sheathed in [[mucous membrane]]. It is responsible for closing off the [[Nasal cavity|nasal passages]] during the act of [[swallowing]], and also for closing off the airway. During sneezing, it protects the nasal passage by diverting a portion of the excreted substance to the mouth.

In [[human]]s, the [[palatine uvula|uvula]] hangs from the end of the soft palate. Touching the uvula or the end of the soft palate evokes a strong [[pharyngeal reflex|gag reflex]] in most people.

===Speech===
A speech sound made with the middle part of the [[tongue]] (dorsum) touching the soft palate is known as a [[velar consonant]].

It is possible for the soft palate to retract and elevate during speech to separate the oral cavity (mouth) from the nasal cavity in order to produce the oral speech sounds. When the soft palate is lowered, air can flow freely through the nasal cavity, thus producing the [[Nasalization|nasal]] speech sounds, such as [m], [n] and [ŋ].

===Modelling===
{{Unclear|section|talk=Talk:Soft_palate#Function::Modelling_section_is_unclear|date=August 2023}}
Within the microstructure of the soft palate lie a variety of variably-oriented fibers that create a nonuniform surface with a nonuniform density distribution. The tissue has been characterized as viscoelastic, nonlinear, and anisotropic in the direction of the fibers. [[Young modulus]] values range from 585&nbsp;Pa at the posterior free edge of the soft palate to 1409&nbsp;Pa where the soft palate attaches to the maxilla.<ref>{{cite journal |doi=10.1597/08-012.1 |pmid=19642755 |title=Biomechanical Properties of the Human Soft Palate |journal=The Cleft Palate-Craniofacial Journal |volume=46 |issue=3 |pages=268–74 |year=2009 |last1=Birch |first1=M. J. |last2=Srodon |first2=P. D. |s2cid=24414466 }}</ref> These properties are useful when quantifying the effects of corrective orthopedic devices such as the Hotz Plate on cleft lip.

Quantitative analyses have been done on bilateral and unilateral cleft palate to better understand geometric differences in cleft palate throughout the course of its development and correction.<ref>{{cite journal |pmid=4524356 |year=1974 |last1=Berkowitz |first1=S |title=Quantitative analysis of cleft palate casts. A geometric study |journal=The Cleft Palate Journal |volume=11 |pages=134–61 |last2=Krischer |first2=J |last3=Pruzansky |first3=S }}</ref> Despite the difficulty in finding common, comparable landmarks between normal soft palates and cleft palates, analytical methods have been devised to assess differences in degree of curvature of the alveolar crest, two-dimensional and three-dimensional surface area, and slope of the alveolar crest.

Finite element analysis has demonstrated effective modeling of soft-palate extension and movement. It has also been an effective tool for evaluating the craniofacial effects of corrective orthopedic devices and cleft lip.

==Clinical significance==

===Disease===
{{See also|Oral pathology}}
Pathology of the soft palate includes [[mucosa]]l lesions such as [[pemphigus vulgaris|pemphigus vulgaris dsg - 3]], [[herpangina]] and [[migratory stomatitis]],<ref name="MS">{{cite journal |doi=10.1016/j.jaad.2010.04.016 |pmid=21763590 |title=Migratory stomatitis (ectopic geographic tongue) on the floor of the mouth |journal=Journal of the American Academy of Dermatology |volume=65 |issue=2 |pages=459–60 |year=2011 |last1=Zadik |first1=Yehuda |last2=Drucker |first2=Scott |last3=Pallmon |first3=Sarit }}</ref> and [[muscle|muscular]] conditions such as the [[birth defect|congenital]] [[cleft palate]] and [[cleft uvula]].

[[File:Streptococcal pharyngitis.jpg|thumb|Palatal [[petechiae]].]]
[[Petechiae]] on the soft palate are mainly associated with [[streptococcal pharyngitis]],<ref>[http://www.entnet.org/HealthInformation/tonsillitis.cfm Fact Sheet: Tonsillitis] {{webarchive|url=https://web.archive.org/web/20111126154410/http://www.entnet.org/HealthInformation/tonsillitis.cfm |date=2011-11-26 }} from American Academy of Otolaryngology. "Updated 1/11". Retrieved November 2011</ref> and as such it is an uncommon but highly [[Sensitivity and specificity|specific]] finding.<ref name=Review06>{{cite journal |pmid=17137534 |year=2006 |last1=Brook |first1=I |title=Management of group a beta-hemolytic streptococcal pharyngotonsillitis in children |journal=The Journal of Family Practice |volume=55 |issue=12 |pages=S1–11; quiz S12 |last2=Dohar |first2=J. E. }}</ref> 10 to 30 percent of palatal petechiae cases are estimated to be caused by suction, which can be habitual or secondary to [[fellatio]].<ref>[https://books.google.com/books?id=EaIieB9kX_gC&pg=PA134 Page 134] {{webarchive|url=https://web.archive.org/web/20180504184506/https://books.google.com/books?id=EaIieB9kX_gC&pg=PA134 |date=2018-05-04 }} in: {{cite book |author1=Michael Glick |author2=Greenberg, Martin Harry |author3=Burket, Lester W. |title=Burket's oral medicine: diagnosis & treatment |publisher=BC Decker |location=Hamilton, Ont |year=2003 |isbn=978-1-55009-186-1 }}</ref>

==Additional images==
<gallery>
 File:Uvula without tonsils.jpg|Soft palate without tonsils (after [[tonsillectomy]])
 File:Gray994.png|Sagittal section of nose mouth, pharynx, and larynx.
 File:Gray1014.png|The mouth cavity. The cheeks have been slit transversely and the tongue pulled forward.
 Gray855.png|Lateral wall of nasal cavity. (Soft palate visible in lower right)
</gallery>

==See also==
{{Commons}}
{{Anatomy-terms}}
* [[Palatine tonsil]]
* [[Velotrace]]

==References==
{{Reflist}}

==External links==
* [https://web.archive.org/web/20060717044541/http://images.webmd.com/images/hw/media65/medical/hw/nd551248.jpg Image at WebMD]
* {{SUNYAnatomyFigs|34|01|03}} - "Diagram of the regions of the oral cavity."

{{Mouth anatomy}}
{{Authority control}}

[[Category:Palate]]
[[Category:Human mouth anatomy]]
[[Category:Speech organs]]

[[he:חך#החך הרך]]
[[ja:口蓋#軟口蓋]]