The soft palate (also known as the velum, palatal velum, or muscular palate) is, in

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s, the soft tissue constituting the back of the roof of 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 ...

. The soft palate is part of the palate of the mouth; the other part is the

hard palate The hard palate is a thin horizontal bony plate made up of two bones of the facial skeleton, located in the roof of the mouth. The bones are the palatine process of the maxilla and the horizontal plate of palatine bone. The hard palate spans ...

. The soft palate is distinguished from the hard palate at the front of the mouth in that it does not contain bone.

Structure

Muscles

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 Swallowing, sometimes called deglutition in scientific contexts, is the process in the human or animal body that allows for a substance to pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. Swallowing i ...

# Palatoglossus, involved in

# Palatopharyngeus, involved in

breathing Breathing (or ventilation) is the process of moving air into and from the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxygen. All aerobic creatures need oxygen for cellular ...

# Levator veli palatini, involved in

# Musculus uvulae, which moves the 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 (V₃).

Function

The soft palate is moveable, consisting of

muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

fibers sheathed in mucous membrane. It is responsible for closing off the

nasal passages The human nose is the most protruding part of the face. It bears the nostrils and is the first organ of the respiratory system. It is also the principal organ in the olfactory system. The shape of the nose is determined by the nasal bones ...

during the act of

, 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 humans, the uvula hangs from the end of the soft palate. Touching the uvula or the end of the soft palate evokes a strong 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. If this separation is incomplete, air escapes through the nose, causing speech to be perceived as

nasal Nasal is an adjective referring to the nose, part of human or animal anatomy. It may also be shorthand for the following uses in combination: * With reference to the human nose: ** Nasal administration, a method of pharmaceutical drug delivery ** ...

Modelling

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 Pa at the posterior free edge of the soft palate to 1409 Pa where the soft palate attaches to the maxilla. 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. 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

Pathology of the soft palate includes

mucosa A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...

l lesions such as pemphigus vulgaris dsg - 3, herpangina and migratory stomatitis, and muscular conditions such as the

congenital A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...

cleft palate and cleft uvula. Streptococcal pharyngitis

Petechiae A petechia () is a small red or purple spot (≤4 mm in diameter) that can appear on the skin, conjunctiva, retina, and mucous membranes which is caused by haemorrhage of capillaries. The word is derived from Italian , 'freckle,' of obscure origin ...

on the soft palate are mainly associated with

streptococcal pharyngitis Streptococcal pharyngitis, also known as streptococcal sore throat (strep throat), is pharyngitis (an infection of the pharynx, the back of the throat) caused by ''Streptococcus pyogenes'' a gram-positive, group A streptococcus. Common symptom ...

, and as such it is an uncommon but highly specific finding. 10 to 30 percent of palatal petechiae cases are estimated to be caused by suction, which can be habitual or secondary to fellatio.Page 134
in:

Additional images

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)

References

External links

Image at WebMD
* - "Diagram of the regions of the oral cavity." {{Authority control Palate palate Speech organs he:חך#החך הרך ja:口蓋#軟口蓋