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Digastric
The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') 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 (cranial nerve V), and the posterior belly is innervated via the facial nerve (cranial nerve VII). It may act to depress the mandible or elevate the hyoid bone. The term "digastric muscle" refers to this specific muscle even though there are other muscles in the body to feature two bellies. Anatomy The digastric muscle consists of two muscular bellies united by an intermediate tendon with the posterior belly longer than the anterior belly. The two bellies of the digastric muscle have different embryological origins - the an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digastric Muscle
The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') 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 (cranial nerve V), and the posterior belly is innervated via the facial nerve (cranial nerve VII). It may act to depress the mandible or elevate the hyoid bone. The term "digastric muscle" refers to this specific muscle even though there are other muscles in the body to feature two bellies. Anatomy The digastric muscle consists of two muscular bellies united by an intermediate tendon with the posterior belly longer than the anterior belly. The two bellies of the digastric muscle have different embryological origins - the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facial Nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerve typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI (abducens nerve) and anterior to cranial nerve VIII (vestibulocochlear nerve). The facial nerve also supplies preganglionic parasympathetic fibers to several head and neck ganglia. The facial and intermediate nerves can be collectively referred to as the nervus intermediofacialis. The path of the facial nerve can be divided into six segments: # intracranial (cisternal) segment (from brainstem pons to internal auditory canal) # meatal (canalicular) segment (with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digastric Branch Of Facial Nerve
The digastric branch of facial nerve provides motor innervation to the posterior belly of the digastric muscle. It branches from the facial nerve (CN VII) near to the stylomastoid foramen as the CN VII exits the facial canal The facial canal (also known as the Fallopian canal) is a Z-shaped canal in the temporal bone of the skull. It extends between the internal acoustic meatus and stylomastoid foramen. It transmits the facial nerve (CN VII) (after which it is nam ... (it thus branches proximal to the parotid plexus of facial nerve). It commonly arises in common with the stylohyoid branch of facial nerve. References External links * () * () * http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-5.HTM Facial nerve {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mylohyoid Nerve
The mylohyoid nerve (or nerve to mylohyoid) 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. Structure Origin The mylohyoid nerve is a mixed (motor-sensory) branch of the inferior alveolar nerve (which is a branch of the mandibular nerve (CN V3) that is itself a branch of the trigeminal nerve (CN V)). It arises just before it enters the mandibular foramen. Course It pierces the sphenomandibular ligament. It descends in a groove on the deep surface of the ramus of the mandible. When it reaches the under surface of the mylohyoid muscle, it gives branches to the mylohyoid muscle and the anterior belly of the digastric muscle. Distribution Motor The mylohyoid nerve supp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suprahyoid Muscles
The suprahyoid muscles are four muscles located above the hyoid bone in the neck. They are the digastric, stylohyoid, geniohyoid, and mylohyoid muscles. They are all pharyngeal muscles, with the exception of the geniohyoid muscle. The digastric is uniquely named for its two bellies. Its posterior belly rises from the mastoid process of the cranium and slopes downward and forward. The anterior belly arises from the digastric fossa on the inner surface of the mandibular body, which slopes downward and backward. The two bellies connect at the intermediate tendon. The intermediate tendon passes through a connective tissue loop attached to the hyoid bone. The mylohyoid muscles are thin, flat muscles that form a sling inferior to the tongue supporting the floor of the mouth. The geniohyoids are short, narrow muscles that contact each other in the midline. The stylohyoids are long, thin muscles that are nearly parallel with the posterior belly of the digastric muscle. Function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Triangle Of The Neck
The anterior triangle is a region of the neck. Structure The triangle is inverted with its apex inferior to its base which is under the chin. Investing fascia covers the roof of the triangle while visceral fascia covers the floor. Anatomy Muscles: * Suprahyoid muscles - Digastric (Ant and post belly), mylohyoid, geniohyoid and stylohyoid. * Infrahyoid muscles - Omohyoid, sternohyoid, sternothyroid, and thyrohyoid. Nerve supply 2 Bellies of digastric * Anterior: Mylohyoid nerve * Posterior: Facial nerve Stylohyoid: by the facial nerve, by a branch from that to the posterior belly of digastric. Mylohyoid: by its own nerve, a branch of the inferior alveolar (from the mandibular division of trigeminal nerve), which arises just before the parent nerve enters the mandibular foramen, pierces the sphenomandibular ligament, and runs forward on the inferior surface of the mylohyoid, supplying it and the anterior belly of the digastric. Geniohyoid: by a branch from the hypoglossa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occipital Artery
The occipital artery is a branch of the external carotid artery that provides arterial supply to the back of the scalp, sternocleidomastoid muscles, and deep muscles of the back and neck. Structure Origin The occipital artery arises from (the posterior aspect of) the external carotid artery (some 2 cm distal to the origin of the external carotid artery). Course and relations At its origin, the hypoglossal nerve (CN XII) crosses artery superficially as the nerve passes posteroanteriorly. The artery passes superoposteriorly deep to the posterior belly of the digastricus muscle. It crosses the internal carotid artery and vein, the vagus nerve (CN X), accessory nerve (CN XI), and hypoglossal nerve (CN XII). It next ascends to the interval between the transverse process of the atlas and the mastoid process of the temporal bone, and passes horizontally backward, grooving the surface of the latter bone, being covered by the sternocleidomastoideus, splenius capitis, longi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigeminal
In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chewing; it is the most complex of the cranial nerves. Its name (''trigeminal'', ) derives from each of the two nerves (one on each side of the pons) having three major branches: the ophthalmic nerve (V), the maxillary nerve (V), and the mandibular nerve (V). The ophthalmic and maxillary nerves are purely sensory, whereas the mandibular nerve supplies motor as well as sensory (or "cutaneous") functions. Adding to the complexity of this nerve is that autonomic nerve fibers as well as special sensory fibers (taste) are contained within it. The motor division of the trigeminal nerve derives from the basal plate of the embryonic pons, and the sensory division originates in the cranial neural crest. Sensory information from the face and body is proc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylohyoideus
The stylohyoid muscle is one of the suprahyoid muscles. Its originates from the styloid process of the temporal bone; it inserts onto hyoid bone. It is innervated by a branch of the facial nerve. It acts draw the hyoid bone upwards and backwards. Structure The stylohyoid is a slender muscle. It is directed inferoanteriorly from its origin towards its insertion. It is perforated near its insertion by the intermediate tendon of the digastric muscle. Origin The muscle arises from the posterior surface of the temporal styloid process; it arises near the base of the process. It arises by a small tendon of origin. Insertion The muscle inserts onto the body of hyoid bone at the junction of the body and greater cornu. It passes anterior to the intermediate tendon of the digastric muscle and is inserted immediately superior to that of the superior belly of omohyoid muscle. Vasculature The stylohyoid muscle receives arterial supply branches of the facial artery, posterior auricul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submandibular Gland
The paired submandibular glands (historically known as submaxillary glands) are major salivary glands located beneath the floor of the mouth. In adult humans, they each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as parotid gland secretion rises to 50%. The average length of the normal adult human submandibular salivary gland is approximately 27 mm, while the average width is approximately 14.3 mm. Structure Each submandibular gland is divided into a superficial lobe and a deep lobe, the two being separated by the mylohyoid muscle: * The superficial lobe comprises most of the gland, with the mylohyoid muscle runs under it * The deep lobe is the smaller part Submandibular duct Secretions are delivered into the submandibular duct on the deep portion after which they hook around the posterior edge of the mylohyoid muscle and proceed on the superior surface laterally. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastoid Process
The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, the mastoid part articulates with two other bones. Etymology The word "mastoid" is derived from the Greek word for "breast", a reference to the shape of this bone. Surfaces Outer surface Its outer surface is rough and gives attachment to the occipitalis and posterior auricular muscles. It is perforated by numerous foramina (holes); for example, the mastoid foramen is situated near the posterior border and transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater. The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital. Mastoid process The mastoid process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
