Mandibular canal | |
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![]() The permanent teeth, viewed from the right. The external layer of bone has been partly removed and the maxillary sinus has been opened. | |
Details | |
Identifiers | |
Latin | canalis mandibulae |
MeSH | D000088263 |
TA98 | A02.1.15.030 |
TA2 | 867 |
FMA | 59473 |
Anatomical terms of bone |
In human anatomy, the mandibular canal is a canal within the mandible that contains the inferior alveolar nerve, inferior alveolar artery, and inferior alveolar vein. It runs obliquely downward and forward in the ramus, and then horizontally forward in the body, where it is placed under the alveoli and communicates with them by small openings.
On arriving at the incisor teeth, it turns back to communicate with the mental foramen, giving off a small canal known as the mandibular incisive canal, which run to the cavities containing the incisor teeth. [1] It carries branches of the inferior alveolar nerve and artery.
The mandibular canal is continuous with tow foramina: the mental foramen which opens in the mental region of the mandible and carried the distal fibres of the inferior alveolar nerve as the mental nerve; and the mandibular foramen on medial aspect of ramus, into which the mandibular nerve enters to become the inferior alveolar nerve. The mandibular canal often runs close to the apices of the third molar tooth, and the inferior alveolar nerve can become damaged during removal of this tooth, causing sensory disturbance in the distribution of the nerve. This is sometimes the case for the second or first molar teeth, and care must be taken during removal or root canal treatment in such cases to prevent nerve injury or extrusion of root canal filling materials. [2]
Several variations of the mandibular canal exist with varying frequency. The most common variant is the retromolar canal (~10 % of canals), whereby a branch is given off in the mandibular ramus which terminates in the retromolar region of the mandible. The retromolar canal may cause bleeding during surgery in the retromolar region such as removal of mandibular third molar teeth. Other variants include a bifid canal with a branch (~41%): [3] following the course of the main mandibular canal before re-joining it (forward or buccolingual type); terminating at the apex of a tooth, usually the molar teeth (dental type); opening as an accessory mental foramen. [4] A trifid mandibular canal variation has also been described. [5] [6]
Articles related to anatomy include:
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.
The inferior alveolar nerve (IAN) (also the inferior dental nerve) is a sensory branch of the mandibular nerve (CN V3) (which is itself the third branch of the trigeminal nerve (CN V)). The nerve provides sensory innervation to the lower/mandibular teeth and their corresponding gingiva as well as a small area of the face (via its mental nerve).
The medial 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).
The buccal nerve is a sensory nerve of the face arising from the mandibular nerve. It conveys sensory information from the skin of the cheek, and parts of the oral mucosa, periodontium, and gingiva.
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 lingual nerve carries sensory innervation from the anterior two-thirds of the tongue. It contains fibres from both the mandibular division of the trigeminal nerve (CN V3) and from the facial nerve (CN VII). The fibres from the trigeminal nerve are for touch, pain and temperature (general sensation), and the ones from the facial nerve are for taste (special sensation).
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 anteriorly inside the mandible, supplying 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 mylohyoid nerve is a mixed nerve of the head. It is a branch of the inferior alveolar nerve. It provides motor innervation the mylohyoid muscle, and the anterior belly of the digastric muscle. It provides sensory innervation to part of the submental area, and sometimes also the mandibular (lower) molar teeth, requiring local anaesthesia for some oral procedures.
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 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.
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 inferior dental plexus is a nerve plexus formed by sensory branches of the inferior alveolar nerve. The plexus issues dental branches and gingival branches; the small dental branches provide sensory innervation to the lower/mandibular teeth.
Mandibular fracture, also known as fracture of the jaw, is a break through the mandibular bone. In about 60% of cases the break occurs in two places. It may result in a decreased ability to fully open the mouth. Often the teeth will not feel properly aligned or there may be bleeding of the gums. Mandibular fractures occur most commonly among males in their 30s.
Inferior alveolar nerve block is a nerve block technique which induces anesthesia (numbness) in the areas of the mouth and face innervated by one of the inferior alveolar nerves which are paired on the left and right side. These areas are the skin and mucous membranes of the lower lip, the skin of the chin, the lower teeth and the labial gingiva of the anterior teeth, all unilaterally to the midline of the side on which the block is administered. However, depending on technique, the long buccal nerve may not be anesthetized by an IANB and therefore an area of buccal gingiva adjacent to the lower posterior teeth will retain normal sensation unless that nerve is anesthetized separately, via a (long) buccal nerve block. The inferior alveolar nerve is a branch of the mandibular nerve, the third division of the trigeminal nerve. This procedure attempts to anaesthetise the inferior alveolar nerve prior to it entering the mandibular foramen on the medial surface of the mandibular ramus.
The mandibular incisive canal is a bilaterally paired bony canal within the anterior portion of the mandible that extends from the mental foramen (usually) to near the ipsilateral lateral incisor teeth.
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.
In human anatomy, the mouth is the first portion of the alimentary canal that receives food and produces saliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth.
The pterygomandibular space is a fascial space of the head and neck. It is a potential space in the head and is paired on each side. It is located between the lateral pterygoid muscle and the medial surface of the ramus of the mandible. The pterygomandibular space is one of the four compartments of the masticator space.
Mandibular setback surgery is a surgical procedure performed along the occlusal plane to prevent bite opening on the anterior or posterior teeth and retract the lower jaw for both functional and aesthetic effects in patients with mandibular prognathism. It is an orthodontic surgery that is a form of reconstructive plastic surgery. There are three main types of procedures for mandibular setback surgery: Bilateral Sagittal Split Osteotomy (BSSO), Intraoral Vertical Ramus Osteotomy (IVRO) and Extraoral Ramus Osteotomy (EVRO), depending on the magnitude of mandibular setback for each patient. Postoperative care aims to minimise postoperative complications, complications includes bite changes, relapse and nerve injury.
This article incorporates text in the public domain from page 173 of the 20th edition of Gray's Anatomy (1918)