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Platysma
The platysma muscle is a superficial muscle of the human neck that overlaps the sternocleidomastoid. It covers the anterior surface of the neck superficially. When it contracts, it produces a slight wrinkling of the neck, and a "bowstring" effect on either side of the neck. Structure The platysma muscle is a broad sheet of muscle arising from the fascia covering the upper parts of the pectoralis major muscle and deltoid muscle. Its fibers cross the clavicle, and proceed obliquely upward and medially along the side of the neck. This leaves the inferior part of the neck in the midline deficient of significant muscle cover. Fibres at the front of the muscle from the left and right sides intermingle together below and behind the mandibular symphysis, the junction where the two lateral halves of the mandible are fused at an early period of life (although not a true symphysis). Fibres at the back of the muscle cross the mandible, some being inserted into the bone below the oblique li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervical Branch Of The Facial Nerve
The cervical branch of the facial nerve is a nerve in the neck. It is a branch of the facial nerve (VII). It supplies the platysma muscle, among other functions. Structure The cervical branch of the facial nerve is a branch of the facial nerve (VII). It runs forward beneath the platysma muscle, and forms a series of arches across the side of the neck over the suprahyoid region. One branch descends to join the cervical cutaneous nerve from the cervical plexus The cervical plexus is a plexus of the anterior rami of the first four cervical spinal nerves which arise from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the me .... Function The lateral part of the cervical branch of the facial nerve supplies the platysma muscle. Additional images File:Lateral head anatomy detail.jpg, Lateral head anatomy detail File:Slide1BAB.JPG, Lateral head anatomy detail. Dissection the newborn File:Sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervical Branch Of The Facial Nerve
The cervical branch of the facial nerve is a nerve in the neck. It is a branch of the facial nerve (VII). It supplies the platysma muscle, among other functions. Structure The cervical branch of the facial nerve is a branch of the facial nerve (VII). It runs forward beneath the platysma muscle, and forms a series of arches across the side of the neck over the suprahyoid region. One branch descends to join the cervical cutaneous nerve from the cervical plexus The cervical plexus is a plexus of the anterior rami of the first four cervical spinal nerves which arise from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the me .... Function The lateral part of the cervical branch of the facial nerve supplies the platysma muscle. Additional images File:Lateral head anatomy detail.jpg, Lateral head anatomy detail File:Slide1BAB.JPG, Lateral head anatomy detail. Dissection the newborn File:Sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 in place. The mandible sits beneath the maxilla. It is the only movable bone of the skull (discounting the ossicles of the middle ear). It is connected to the temporal bones by the temporomandibular joints. The bone is formed in the fetus from a fusion of the left and right mandibular prominences, and the point where these sides join, the mandibular symphysis, is still visible as a faint ridge in the midline. Like other symphyses in the body, this is a midline articulation where the bones are joined by fibrocartilage, but this articulation fuses together in early childhood.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, p. 59 The word "mandible" derives from the Latin word ''mandibula'', "jawbone" (literally "one used for chewing"), from '' mandere'' "to chew" and ''-bula'' (ins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporalis Muscle
In anatomy, the temporalis muscle, also known as the temporal muscle, is one of the muscles of mastication (chewing). It is a broad, fan-shaped convergent muscle on each side of the head that fills the temporal fossa, superior to the zygomatic arch so it covers much of the temporal bone.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, page 98''Temporal'' refers to the head's temples. Structure In humans, the temporalis muscle arises from the temporal fossa and the deep part of temporal fascia. This is a very broad area of attachment. It passes medial to the zygomatic arch. It forms a tendon which inserts onto the coronoid process of the mandible, with its insertion extending into the retromolar fossa posterior to the most distal mandibular molar.Human Anatomy, Jacobs, Elsevier, 2008, page 194 In other mammals, the muscle usually spans the dorsal part of the skull all the way up to the medial line. There, it may be attached to a sagittal cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Masseter Muscle
In human 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. Structure The masseter is a thick, somewhat quadrilateral muscle, consisting of three heads, superficial, deep and coronoid. The fibers of superficial and deep heads are continuous at their insertion. Superficial head The superficial head, the larger, arises by a thick, tendinous aponeurosis from the temporal process of the zygomatic bone, and from the anterior two-thirds of the inferior border of the zygomatic arch. Its fibers pass inferior and posterior, to be inserted into the angle of the mandible and inferior half of the lateral surface of the ramus of the mandible. Deep head The deep head is much smaller, and more muscular in texture. It arises from the posterior third of the low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human 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 in place. The mandible sits beneath the maxilla. It is the only movable bone of the skull (discounting the ossicles of the middle ear). It is connected to the temporal bones by the temporomandibular joints. The bone is formed in the fetus from a fusion of the left and right mandibular prominences, and the point where these sides join, the mandibular symphysis, is still visible as a faint ridge in the midline. Like other symphyses in the body, this is a midline articulation where the bones are joined by fibrocartilage, but this articulation fuses together in early childhood.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, p. 59 The word "mandible" derives from the Latin word ''mandibula'', "jawbone" (literally "one used for chewing"), from '' mandere'' "to chew" and ''-bula' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Jugular Vein
The external jugular vein receives the greater part of the blood from the exterior of the cranium and the deep parts of the face, being formed by the junction of the posterior division of the retromandibular vein with the posterior auricular vein. Structure It commences in the substance of the parotid gland, on a level with the angle of the mandible, and runs perpendicularly down the neck, in the direction of a line drawn from the angle of the mandible to the middle of the clavicle superficial to the sternocleidomastoideus. In its course it crosses the sternocleidomastoideus obliquely, and in the subclavian triangle perforates the deep fascia, and ends in the subclavian vein lateral to or in front of the scalenus anterior, piercing the roof of the posterior triangle. It is separated from the sternocleidomastoideus by the investing layer of the deep cervical fascia, and is covered by the platysma, the superficial fascia, and the integument; it crosses the cutaneous cervical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomaticus Major Muscle
The zygomaticus major muscle is a muscle of the human body. It extends from each zygomatic arch ( cheekbone) to the corners of the mouth. It is a muscle of facial expression which draws the angle of the mouth superiorly and posteriorly to allow one to smile. Bifid zygomaticus major muscle is a notable variant, and may cause cheek dimples. Structure The zygomaticus major muscle originates from the upper margin of the temporal process, part of the lateral surface of the zygomatic bone. It inserts into tissue at the corner of the mouth. Nerve supply The zygomaticus major muscle is supplied by a buccal branch and a zygomatic branch of the facial nerve (VII). Variation The zygomaticus major muscle may occur in a bifid form, with two fascicles that are partially or completely separate from each other but adjacent. Usually a single unit, dimples are caused by variations in form. It is thought that cheek dimples are caused by bifid zygomaticus major muscle. Function The zy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subcutaneous Tissue
The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and macrophages. The subcutaneous tissue is derived from the mesoderm, but unlike the dermis, it is not derived from the mesoderm's dermatome region. It consists primarily of loose connective tissue, and contains larger blood vessels and nerves than those found in the dermis. It is a major site of fat storage in the body. In arthropods, a hypodermis can refer to an epidermal layer of cells that secretes the chitinous cuticle. The term also refers to a layer of cells lying immediately below the epidermis of plants. Structure * Fibrous bands anchoring the skin to the deep fascia * Collagen and elastin fibers attaching it to the dermis * Fat is absent from the eyelids, clitoris, penis, much of pinna, and scrotum * Blood vessels on rout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectoralis Major
The pectoralis major () is a thick, fan-shaped or triangular convergent muscle, situated at the chest of the human body. It makes up the bulk of the chest muscles and lies under the breast. Beneath the pectoralis major is the pectoralis minor, a thin, triangular muscle. The pectoralis major's primary functions are flexion, adduction, and internal rotation of the humerus. The pectoral major may colloquially be referred to as "pecs", "pectoral muscle", or "chest muscle", because it is the largest and most superficial muscle in the chest area. Structure It arises from the anterior surface of the sternal half of the clavicle from breadth of the half of the anterior surface of the sternum, as low down as the attachment of the cartilage of the sixth or seventh rib; from the cartilages of all the true ribs, with the exception, frequently, of the first or seventh, and from the aponeurosis of the abdominal external oblique muscle. From this extensive origin the fibers converge towa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbicularis Oris Muscle
In human anatomy, the orbicularis oris muscle is a complex of muscles in the lips that encircles the mouth. It is a sphincter, or circular muscle, but it is actually composed of four independent quadrants that interlace and give only an appearance of circularity.Saladin, "Anatomy & Physiology: The Unity of Form and Function". 5th edition. McGraw Hill. Page 330 It is also one of the muscles used in the playing of all brass instruments and some woodwind instruments. This muscle closes the mouth and puckers the lips when it contracts. Structure The orbicularis oris is not a simple sphincter muscle like the orbicularis oculi; it consists of numerous strata of muscular fibers surrounding the orifice of the mouth, but having different direction. It consists partly of fibers derived from the other facial muscles which are inserted into the lips, and partly of fibers proper to the lips. Of the former, a considerable number are derived from the buccinator and form the deeper stratum of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandibular Symphysis
In human anatomy, the facial skeleton of the skull the external surface of the mandible is marked in the median line by a faint ridge, indicating the mandibular symphysis (Latin: ''symphysis menti'') or line of junction where the two lateral halves of the mandible typically fuse at an early period of life (1-2 years). It is not a true symphysis as there is no cartilage between the two sides of the mandible. This ridge divides below and encloses a triangular eminence, the mental protuberance, the base of which is depressed in the center but raised on either side to form the mental tubercle. The lowest (most inferior) end of the mandibular symphysis — the point of the chin — is called the "menton". It serves as the origin for the geniohyoid and the genioglossus The genioglossus is one of the paired extrinsic muscles of the tongue. The genioglossus is the major muscle responsible for protruding (or sticking out) the tongue. Structure Genioglossus is the fan-shaped extrinsic t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
