| Mandibular notch | |
|---|---|
 Position of mandibular notch in skull, shown in red. | |
 Position of mandibular notch in mandible, shown in red. | |
| Details | |
| Part of | mandible |
| System | skeletal |
| Identifiers | |
| Latin | incisura mandibulae |
| TA98 | A02.1.15.034 A02.1.15.008 |
| TA2 | 871 |
| FMA | 59481 |
| Anatomical terms of bone | |
The mandibular notch, also known as the sigmoid notch, is a groove in the ramus of the mandible. It is the gap between the coronoid process anteriorly and the condyloid process posteriorly.
The mandibular notch is a concave groove at the top of the ramus of the mandible. It is the gap between the coronoid process anteriorly and the condyloid process posteriorly.
The mandibular notch allows for the passage of the masseteric nerve (a branch of the mandibular nerve (V3) division of the trigeminal nerve), the masseteric artery, and the masseteric vein.
The mandibular notch may be palpated to locate the parotid duct, [1] the facial artery, [1] the facial vein, [1] and the medial pterygoid muscle. [2]
The mandibular notch can be found in other mammals, such as dogs and cats. [1] There can be significant variation in its shape even within the same species. [3] Archaeological evidence shows that the mandibular notch is different in other hominidae, such as neanderthals, and may be asymmetrical. [4]
In anatomy, the temporomandibular joints (TMJ) are the two joints connecting the jawbone to the skull. It is a bilateral synovial articulation between the temporal bone of the skull above and the mandible below; it is from these bones that its name is derived. This joint is unique in that it is a bilateral joint that functions as one unit. Since the TMJ is connected to the mandible, the right and left joints must function together and therefore are not independent of each other.
The digastric muscle is a bilaterally paired suprahyoid muscle located under the jaw. Its posterior belly is attached to the mastoid notch of temporal bone, and its anterior belly is attached to the digastric fossa of mandible; the two bellies are united by an intermediate tendon which is held in a loop that attaches to the hyoid bone. The anterior belly is innervated via the mandibular nerve, and the posterior belly is innervated via the facial nerve. It may act to depress the mandible or elevate the hyoid bone.
The mandibular foramen is an opening on the internal surface of the ramus of the mandible. It allows for divisions of the mandibular nerve and blood vessels to pass through.
In anatomy, the masseter is one of the muscles of mastication. Found only in mammals, it is particularly powerful in herbivores to facilitate chewing of plant matter. The most obvious muscle of mastication is the masseter muscle, since it is the most superficial and one of the strongest.
The auriculotemporal nerve is a sensory branch of the mandibular nerve (CN V3) that runs with the superficial temporal artery and vein, and provides sensory innervation to parts of the external ear, scalp, and temporomandibular joint. The nerve also conveys post-ganglionic parasympathetic fibres from the otic ganglion to the parotid gland.
The facial artery is a branch of the external carotid artery that supplies structures of the superficial face.
The mental foramen is one of two foramina (openings) located on the anterior surface of the mandible. It is part of the mandibular canal. It transmits the terminal branches of the inferior alveolar nerve and the mental vessels.
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 condyle and the constricted portion which supports it, the neck.
The inferior alveolar artery is an artery of the head. It is a branch of the maxillary artery. It descends through the infratemporal fossa as part of a neurovascular bundle with the inferior alveolar nerve and vein to the mandibular foramen where it enters and passes anterior-ward inside the mandible, suplying the body of mandible and the dental pulp of the lower molar and premolar teeth. Its terminal incisor branch supplies the rest of the lower teeth. Its mental branch exits the mandibula anteriorly through the mental foramen to supply adjacent lip and skin.
The mental nerve is a sensory nerve of the face. It is a branch of the posterior trunk of the inferior alveolar nerve, itself a branch of the mandibular nerve (CN V3), itself a branch of the trigeminal nerve (CN V). It provides sensation to the front of the chin and the lower lip, as well as the gums of the anterior mandibular (lower) teeth. It can be blocked with local anaesthesia for procedures on the chin, lower lip, and mucous membrane of the inner cheek. Problems with the nerve cause chin numbness.
The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible.
The retromandibular vein is a major vein of the face. It is formed within the parotid gland by the confluence of the maxillary vein, and superficial temporal vein. It descends in the gland and splits into two branches upon emerging from the gland. Its anterior branch then joins the (anterior) facial vein forming the common facial vein, while its posterior branch joins the posterior auricular vein forming the external jugular vein.
The infratemporal fossa is an irregularly shaped cavity that is a part of the skull. It is situated below and medial to the zygomatic arch. It is not fully enclosed by bone in all directions. It contains superficial muscles, including the lower part of the temporalis muscle, the lateral pterygoid muscle, and the medial pterygoid muscle. It also contains important blood vessels such as the middle meningeal artery, the pterygoid plexus, and the retromandibular vein, and nerves such as the mandibular nerve (CN V3) and its branches.
The posterior ethmoidal nerve is a nerve of the head. It is a branch of the nasociliary nerve (itself a branch of the ophthalmic nerve (CN V1)). It provides sensory innervation to the sphenoid sinus and ethmoid sinus, and part of the dura mater in the anterior cranial fossa.
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 temporomandibular joint.
The mandibular fossa, also known as the glenoid fossa in some dental literature, is the depression in the temporal bone that articulates with the mandible.
In human anatomy, the mandible's coronoid process is a thin, triangular eminence, which is flattened from side to side and varies in shape and size. Its anterior border is convex and is continuous below with the anterior border of the ramus. Its posterior border is concave and forms the anterior boundary of the mandibular notch. The lateral surface is smooth, and affords insertion to the temporalis and masseter muscles. Its medial surface gives insertion to the temporalis, and presents a ridge which begins near the apex of the process and runs downward and forward to the inner side of the last molar tooth.
The following outline is provided as an overview of and topical guide to human anatomy:
The anterior auricular muscle, the smallest of the three auricular muscles, is thin and fan-shaped, and its fibers are pale and indistinct. It arises from the lateral edge of the epicranial aponeurosis, and its fibers converge to be inserted into a projection on the front of the helix.
In jawed vertebrates, the mandible, lower jaw, or jawbone is a bone that makes up the lower – and typically more mobile – component of the mouth.
This article incorporates text in the public domain from page 174 of the 20th edition of Gray's Anatomy (1918)
