The sublingual space is a
fascial space of the head and neck (sometimes also termed fascial spaces or tissue spaces). It is a
potential space located below the mouth and above the
mylohyoid muscle, and is part of the suprahyoid group of fascial spaces.
Location and structure
Anatomic boundaries
The sublingual space is V-shaped, with the apex pointing to the anterior. Its boundaries are:
* the
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 ...
of the
floor of mouth and the tongue
superior
Superior may refer to:
*Superior (hierarchy), something which is higher in a hierarchical structure of any kind
Places
*Superior (proposed U.S. state), an unsuccessful proposal for the Upper Peninsula of Michigan to form a separate state
*Lake ...
ly
* the mylohyoid muscle
inferior
Inferior may refer to:
* Inferiority complex
* An Anatomical terms of location#Superior and inferior, anatomical term of location
* Inferior angle of the scapula, in the human skeleton
*Inferior (book), ''Inferior'' (book), by Angela Saini
* ''The ...
ly
* the
medial
Medial may refer to:
Mathematics
* Medial magma, a mathematical identity in algebra Geometry
* Medial axis, in geometry the set of all points having more than one closest point on an object's boundary
* Medial graph, another graph that re ...
surface of the
mandible anterolaterally
* the muscles along the base of the tongue (
geniohyoid and
genioglossus muscles)
posteriorly
* medially, the intrinsic muscles of the tongue and genioglossus separate the two halves of the sublingual space.
Communications
The sublingual space communicates posteriorly around the posterior free border of the mylohyoid muscle with the
submandibular space
The submandibular space is a fascial space of the head and neck (sometimes also termed fascial spaces or tissue spaces). It is a potential space, and is paired on either side, located on the superficial surface of the mylohyoid muscle between the ...
.
Infections of the sublingual space may also erode through the mylohyoid, or spread via the lymphatics to the submandibular and
submental space
The submental space is a fascial space of the head and neck (sometimes also termed fascial spaces or tissue spaces). It is a potential space located between the mylohyoid muscle superiorly, the platysma muscle inferiorly, under the chin in the m ...
s.
Contents
The sublingual space contains:
* a number of blood vessels and nerves, e.g. the
lingual artery and
nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system.
A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
, the
hypoglossal nerve and the
glossopharyngeal nerve.
* the
sublingual salivary gland
The paired sublingual glands are major salivary glands in the mouth. 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 sal ...
.
Saliva
Saliva (commonly referred to as spit) is an extracellular fluid produced and secreted by salivary glands in the mouth. In humans, saliva is around 99% water, plus electrolytes, mucus, white blood cells, epithelial cells (from which DNA can be ...
from the sublingual gland drains through several small excretory ducts in the floor of the mouth. Sometimes a more distinctive duct can be recognized, known as
Bartholin's duct.
* the deep part of 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 stimula ...
and the submandibular duct (
Wharton's duct)
* some
extrinsic tongue muscle fibers
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
.
Clinical relevance

This space may be created by pathology, such as the spread of
pus in an infection, e.g.
odontogenic infections. A
periapical abscess may spread into the sublingual space if the apex of the tooth is above the level of attachment of mylohyoid, and the infection erodes through the lingual cortical plate of the mandible.
Signs and symptoms of a sublingual space infection might include a firm, painful swelling in the anterior part of the floor of the mouth. A sublingual abscess may elevate the tongue and cause drooling or
dysphagia (difficulty swallowing). There is usually little swelling visible on the face outside the mouth.
If the space contains pus, the usual treatment is by
incision and drainage. The site of the incision is intra-oral, made lateral to sublingual plica. Incision of the plica itself can result in a
ranula, or an incision placed medial to the plica can damage Wharton's duct, the sublingual artery and veins and the lingual nerve.
Pathology arising from the sublingual gland is rare, however, sublingual gland
neoplasms are predominantly
malignant and thus important to recognize.
Ludwig's angina is a serious infection involving the submandibular, sublingual and submental spaces bilaterally.
Ludwig's angina may extend into the pharyngeal and cervical spaces, and the swelling can compress the airway and cause
dyspnoea (difficulty breathing).
Collectively, the submandibular, sublingual and submental spaces are sometimes termed the perimandibular spaces, or the submaxillary space.
References
{{DEFAULTSORT:Sublingual Space
Fascial spaces of the head and neck
Otorhinolaryngology
Oral and maxillofacial surgery
Mouth