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Masseteric Fascia
The masseteric fascia and parotideomasseteric fascia (or masseteric-parotid fascia) are fascias of the head varyingly described depending upon the source consulted. They may or may not be described as one and the same structure. Descriptions The 42th edition of Gray's Anatomy (2020) describes a parotid-masseteric fascia as a thin and translucent yet tough fascia that covers the parotid duct, buccal branches of facial nerve (CN VII), and branches of the mandibular nerve where these structures lie upon the surface of the masseter muscle. Anteriorly, the fascia is said to overlie the buccal fat pad (that in turn overlies the buccinator muscle) before blending with the epimysium of the buccinator muscle; inferiorly, it is said to become continuous with the investing layer of deep cervical fascia inferior to the inferior margin of the mandible. The masseteric fascia is said to be derived from the deep cervical fascia and be overlied by but separate from the parotid fascia. The Sob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray's Anatomy
''Gray's Anatomy'' is a reference book of human anatomy written by Henry Gray, illustrated by Henry Vandyke Carter, and first published in London in 1858. It has gone through multiple revised editions and the current edition, the 42nd (October 2020), remains a standard reference, often considered "the doctors' bible". Earlier editions were called ''Anatomy: Descriptive and Surgical'', ''Anatomy of the Human Body'' and ''Gray's Anatomy: Descriptive and Applied'', but the book's name is commonly shortened to, and later editions are titled, ''Gray's Anatomy''. The book is widely regarded as an extremely influential work on the subject. Publication history Origins The English anatomist Henry Gray was born in 1827. He studied the development of the endocrine glands and spleen and in 1853 was appointed Lecturer on Anatomy at St George's Hospital Medical School in London. In 1855, he approached his colleague Henry Vandyke Carter with his idea to produce an inexpensive a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 inside the parotid gland, join. It emerges from the parotid gland. It runs forward along the lateral side of the masseter muscle for around 7 cm. In this course, the duct is surrounded by the buccal fat pad. It takes a steep turn at the border of the masseter and passes through the buccinator muscle, opening into the vestibule of the mouth, the region of the mouth between the cheek and the gums, at the parotid papilla, which lies across the second Maxillary (upper) molar tooth. The buccinator acts as a valve that prevents air forcing into the duct, which would cause pneumoparotitis. Running along with the duct superiorly is the transverse facial artery and upper buccal nerve; running along with the duct inferiorly is the lower buccal nerve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buccal Branches Of The Facial Nerve
The buccal branches of the facial nerve (infraorbital branches), are of larger size than the rest of the branches, pass horizontally forward to be distributed below the orbit and around the mouth. Branches The ''superficial branches'' run beneath the skin and above the superficial muscles of the face, which they supply: some are distributed to the procerus, joining at the medial angle of the orbit with the infratrochlear and nasociliary branches of the ophthalmic. The ''deep branches'' pass beneath the zygomaticus and the quadratus labii superioris, supplying them and forming an infraorbital plexus with the infraorbital branch of the maxillary nerve. These branches also supply the small muscles of the nose. The ''lower deep branches'' supply the buccinator and orbicularis oris, and join with filaments of the buccinator branch of the mandibular nerve In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth cranial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandibular Nerve
In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth cranial nerve (CN V). Unlike the other divisions of the trigeminal nerve ( ophthalmic nerve, maxillary nerve) which contain only afferent fibers, the mandibular nerve contains both afferent and efferent fibers. These nerve fibers innervate structures of the lower jaw and face, such as the tongue, lower lip, and chin. The mandibular nerve also innervates the muscles of mastication. Structure The large sensory root emerges from the lateral part of the trigeminal ganglion and exits the cranial cavity through the foramen ovale. Portio minor, the small motor root of the trigeminal nerve, passes under the trigeminal ganglion and through the foramen ovale to unite with the sensory root just outside the skull. The mandibular nerve immediately passes between tensor veli palatini, which is medial, and lateral pterygoid, which is lateral, and gives off a meningeal br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buccal Fat Pad
The buccal fat pad (also called Bichat’s fat pad, after Xavier Bichat, and the buccal pad of fat) is one of several encapsulated fat masses in the cheek. It is a deep fat pad located on either side of the face between the buccinator muscle and several more superficial muscles (including the masseter, the zygomaticus major, and the zygomaticus minor). The inferior portion of the buccal fat pad is contained within the buccal space. It should not be confused with the malar fat pad, which is directly below the skin of the cheek. It should also not be confused with jowl fat pads. It is implicated in the formation of hollow cheeks and the nasolabial fold, but not in the formation of jowls. Nomenclature and structure The buccal fat pad is composed of several parts, although exactly how many parts seems to be a point of disagreement and no single consistent nomenclature of these parts has been observed. It was described as being divided into three lobes, the anterior, intermediate, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epimysium
Epimysium (plural ''epimysia'') (Greek ''epi-'' for on, upon, or above + Greek ''mys'' for muscle) is the fibrous tissue envelope that surrounds skeletal muscle. It is a layer of dense irregular connective tissue which ensheaths the entire muscle and protects muscles from friction against other muscles and bones. It is continuous with fascia and other connective tissue wrappings of muscle including the endomysium and perimysium. It is also continuous with tendons, where it becomes thicker and collagenous. While the epimysium is irregular on muscles, it is regular on tendons. See also *Endomysium The endomysium, meaning ''within the muscle'', is a wispy layer of areolar connective tissue that ensheaths each individual muscle fiber, or muscle cell. It also contains capillaries and nerves. It overlies the muscle fiber's cell membrane: the sa ... * Perimysium References Soft tissue Muscular system {{muscle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buccinator Muscle
The buccinator () is a thin quadrilateral muscle occupying the interval between the maxilla and the mandible at the side of the face. It forms the anterior part of the cheek or the lateral wall of the oral cavity.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, page 91 Structure It arises from the outer surfaces of the alveolar processes of the maxilla and mandible, corresponding to the three pairs of molar teeth and in the mandible, it is attached upon the buccinator crest posterior to the third molar; and behind, from the anterior border of the pterygomandibular raphe which separates it from the constrictor pharyngis superior. The fibers converge toward the angle of the mouth, where the central fibers intersect each other, those from below being continuous with the upper segment of the orbicularis oris, and those from above with the lower segment; the upper and lower fibers are continued forward into the corresponding lip without decussat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Investing Layer Of Deep Cervical Fascia
The investing layer of deep cervical fascia is the most superficial part of the deep cervical fascia, and encloses the whole neck. It is considered by some sources to be incomplete or nonexistent. Attachments It surrounds the neck like a collar, it splits around the sternocleidomastoid muscle and the trapezius muscle. It is attached as; * Posteriorly - Ligamentum nuchae * Anteriorly - Attached to the hyoid bone * Superiorly - (from backwards to forwards); ** External occipital protuberance and Superior nuchal line of occipital bone ** Mastoid process of Temporal bone ** External acoustic meatus ** Lower margin of the zygomatic arch ** Lower border of body of mandible from the angle of mandible to the symphysis menti * Inferiorly - (from backwards to forwards); ** Spine and acromial process of scapula ** Upper surface of the clavicle **Suprasternal notch of manubrium sterni Tracings * Horizontal extent - From ligamentum nuchae when traced forward, the fascia splits and en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 pterygoid muscle consists of two heads. The bulk of the muscle arises as a deep head from just above the medial surface of the lateral pterygoid plate. The smaller, superficial head originates from the maxillary tuberosity and the pyramidal process of the palatine bone. Its fibers pass downward, lateral, and posterior, and are inserted, by a strong tendinous lamina, into the lower and back part of the medial surface of the ramus and angle of the mandible, as high as the mandibular foramen. The insertion joins the masseter muscle to form a common tendinous sling which allows the medial pterygoid and masseter to be powerful elevators of the jaw. Nerve supply The medial pterygoid muscle is supplied by the medial pterygoid nerve, a branch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Pterygoid Muscle
The lateral pterygoid muscle (or external pterygoid muscle) is a muscle of mastication. It has two heads. It lies superior to the medial pterygoid muscle. It is supplied by pterygoid branches of the maxillary artery, and the lateral pterygoid nerve (from the mandibular nerve, CN V3). It depresses and protrudes the mandible. When each muscle works independently, they can move the mandible side to side. Structure The lateral pterygoid muscle has an upper head and a lower head. * The upper head originates on the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone. It inserts onto the articular disc and fibrous capsule of the temporomandibular joint. * The lower head originates on the lateral surface of the lateral pterygoid plate. It inserts onto the pterygoid fovea at the neck of the condyloid process of the mandible. It lies superior to the medial pterygoid muscle. Blood supply The lateral pterygoid muscle is supplied by pterygoid br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parotid Fascia
The parotid fascia in human anatomy is a fascia that builds a closed membrane together with the masseteric fascia. This common membrane sheaths the parotid gland, its excretory duct and the passing out branches of the facial nerve as well. The parotid fascia proceeds of the superficial layer of the deep cervical fascia that splits to cover the gland. At the lateral side of the gland this fascia is called the parotid fascia. The fascia itself is made of two layers: A superficial layer ( lat. ''Lamina superficalis'') that passes cranial into the temporal fascia and lateral into the masseteric fascia, and a deeper layer (lat. ''Lamina profunda'') that covers the Stylohyoid muscle, the styloglossus and the Musculus stylopharyngeus. The superficial layer is attached to the zygomatic arch above and to the mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Cervical Fascia
The deep cervical fascia (or fascia colli in older texts) lies under cover of the platysma, and invests the muscles of the neck; it also forms sheaths for the carotid vessels, and for the structures situated in front of the vertebral column. Its attachment to the hyoid bone prevents the formation of a dewlap. The investing portion of the fascia is attached behind to the ligamentum nuchæ and to the spinous process of the seventh cervical vertebra. The ''alar fascia'' is a portion of the ''deep cervical fascia''. Divisions The deep cervical fascia is often divided into a superficial, middle, and deep layer. The superficial layer is also known as the investing layer of deep cervical fascia. It envelops the trapezius, sternocleidomastoid, and muscles of facial expression. It also contains the submandibular and parotid salivary gland as well as the muscles of mastication (the masseter, pterygoid, and temporalis muscles). The middle layer is also known as the pretracheal fascia. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
