The mandibular notch, also known as the sigmoid notch, is a groove in the

ramus of the mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone ...

. It is the gap between the coronoid process anteriorly and the

condyloid process The condyloid process or condylar process is the process on the human and other mammalian species' mandibles that ends in a condyle, the mandibular condyle. It is thicker than the coronoid process of the mandible and consists of two portions: the ...

posteriorly.

Structure

The mandibular notch is a concave groove at the top of the

. It is the gap between the coronoid process anteriorly and the

posteriorly.

Function

The mandibular notch allows for the passage of the

masseteric nerve The masseteric nerve is a nerve of the face. It is a branch of the mandibular nerve (CN V3). It passes through the mandibular notch to reach masseter muscle. It provides motor innervation the masseter muscle, and sensory innervation to the tempo ...

(a branch of the mandibular nerve (V3) division of the

trigeminal nerve In neuroanatomy, the trigeminal nerve (literal translation, lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for Sense, sensation in the face and motor functions ...

), the

masseteric artery The masseteric artery is small and passes laterally through the mandibular notch to the deep surface of the masseter muscle, which it supplies. It anastomoses with the masseteric branches of the external maxillary artery and with the transvers ...

, and the masseteric vein.

Clinical significance

The mandibular notch may be palpated to locate the

parotid duct The parotid duct or Stensen duct is a salivary duct. It is the route that saliva takes from the major salivary gland, the parotid gland, into the mouth. Structure The parotid duct is formed when several interlobular ducts, the largest ducts insid ...

, the

facial artery The facial artery, formerly called the external maxillary artery, is a branch of the external carotid artery that supplies blood to superficial structures of the medial regions of the face. Structure The facial artery arises in the carotid t ...

, the facial vein, and the

medial pterygoid muscle The medial pterygoid muscle (or internal pterygoid muscle) is a thick, quadrilateral muscle of the face. It is supplied by the mandibular branch of the trigeminal nerve (V). It is important in mastication (chewing). Structure The medial pter ...

Other animals

The mandibular notch can be found in other mammals, such as

dogs The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers ...

and

cats The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

. There can be significant variation in its shape even within the same species. Archaeological evidence shows that the mandibular notch is different in other

hominidae The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic Family (biology), family of primates that includes eight Neontology#Extant taxa versus extinct taxa, extant species in four Genus, genera: ''Orangutan ...

, such as

neanderthal Neanderthals ( ; ''Homo neanderthalensis'' or sometimes ''H. sapiens neanderthalensis'') are an extinction, extinct group of archaic humans who inhabited Europe and Western and Central Asia during the Middle Pleistocene, Middle to Late Plei ...

s, and may be

asymmetrical Asymmetry is the absence of, or a violation of, symmetry (the property of an object being invariant to a transformation, such as reflection). Symmetry is an important property of both physical and abstract systems and it may be displayed in pre ...

Additional images

References

External links

*
Diagram at unc.edu
{{Authority control Bones of the head and neck