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Muscles Of Facial Expression
The facial muscles are a group of striated skeletal muscles supplied by the facial nerve (cranial nerve VII) that, among other things, control facial expression. These muscles are also called mimetic muscles. They are only found in mammals, although they derive from neural crest cells found in all vertebrates. They are the only muscles that attach to the dermis. Structure The facial muscles are just under the skin ( subcutaneous) muscles that control facial expression. They generally originate from the surface of the skull bone (rarely the fascia), and insert on the skin of the face. When they contract, the skin moves. These muscles also cause wrinkles at right angles to the muscles’ action line. Nerve supply The facial muscles are supplied by the facial nerve (cranial nerve VII), with each nerve serving one side of the face. In contrast, the nearby masticatory muscles are supplied by the mandibular nerve, a branch of the trigeminal nerve (cranial nerve V). List of muscl ... [...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 # meatal (canalicular) segment (within the internal auditory canal) # labyrinthine segment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corrugator Supercilii Muscle
The corrugator supercilii muscle is a small, narrow, pyramidal muscle close to the eye. It arises from the medial end of the superciliary arch, and inserts into the deep surface of the skin of the eyebrow. It draws the eyebrow downward and medially, producing the vertical wrinkles of the forehead. Structure The corrugator supercilii muscle is located at the medial end of the eyebrow, beneath the frontalis muscle and just above the orbicularis oculi muscle. It arises from the medial end of the superciliary arch. Its fibers pass upward and laterally, between the palpebral and orbital portions of the orbicularis oculi muscle. It inserts into the deep surface of the skin of the eyebrow, above the middle of the orbital arch. Relations The supratrochlear nerve passes by the corrugator supercilii muscle between it and the frontalis muscle. Function The corrugator supercilii muscle draws the eyebrow downward and medially, producing the vertical wrinkles of the forehead. It is th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depressor Labii Inferioris Muscle
The depressor labii inferioris (or quadratus labii inferioris) is a facial muscle. It helps to lower the bottom lip. Structure The depressor labii inferioris muscle arises from the lateral surface of the mandible. This is below the mental foramen, and the origin may be around 3 cm wide. It inserts on the skin of the lower lip, blending in with the orbicularis oris muscle around 2 cm wide. At its origin, depressor labii is continuous with the fibers of the platysma muscle. Some yellow fat is intermingled with the fibers. Nerve supply The depressor labii inferioris muscle is supplied by the marginal mandibular branch of the facial nerve. Function The depressor labii inferioris muscle helps to depress and everts the lower lip. It is the most important of the muscles of the lower lip for this function. It is an antagonist of the orbicularis oris muscle. It is needed to expose the mandibular (lower) teeth during smiling. Clinical significance Resection The depressor labii ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levator Labii Superioris Alaeque Nasi Muscle
The levator labii superioris alaeque nasi muscle is, translated from Latin, the "lifter of both the upper lip and of the wing of the nose". It has the longest name of any muscle in an animal. The muscle is attached to the upper frontal process of the maxilla and inserts into the skin of the lateral part of the nostril and upper lip. Overview Historically known as Otto's muscle, it dilates the nostril and elevates the upper lip, enabling one to snarl. Elvis Presley is famous for his use of this expression, earning the muscle's nickname "The Elvis muscle". A mnemonic to remember its name is, "Little Ladies Snore All Night." Snore- because it is the labial elevator closest to the nose. The levator labii superioris alaeque nasi is sometimes referred to as the "angular head" of the levator labii superioris muscle. See also * Levator labii superioris * Frontalis muscle The frontalis muscle () is a muscle which covers parts of the forehead of the skull. Some sources consider the fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levator Labii Superioris
The levator labii superioris (pl. ''levatores labii superioris'', also called quadratus labii superioris, pl. ''quadrati labii superioris'') is a muscle of the human body used in facial expression. It is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone. Structure Its medial fibers form the ''angular head'' (also known as the levator labii superioris alaeque nasi muscle,) which arises by a pointed extremity from the upper part of the frontal process of the maxilla and passing obliquely downward and lateralward divides into two slips. One of these is inserted into the greater alar cartilage and skin of the nose; the other is prolonged into the lateral part of the upper lip, blending with the infraorbital head and with the orbicularis oris. The intermediate portion or ''infraorbital head'' arises from the lower margin of the orbit immediately above the infraorbital foramen, some of its fibers being attached to the maxilla, others to the zy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomaticus Minor Muscle
The zygomaticus minor muscle is a muscle of facial expression. It originates from the zygomatic bone, lateral to the rest of the levator labii superioris muscle, and inserts into the outer part of the upper lip. It draws the upper lip backward, upward, and outward and is used in smiling. It is innervated by the facial nerve (VII). Structure The zygomaticus minor muscle originates from the zygomatic bone. It inserts into the tissue around the upper lip, particularly blending its fibres with orbicularis oris muscle. It lies lateral to the rest of levator labii superioris muscle, and medial to its stronger synergist zygomaticus major muscle. It travels at an angle of approximately 30°. It has a mean width of around 0.5 cm. Nerve supply The zygomaticus minor muscle is supplied by the buccal branch of the facial nerve (VII). Variation The zygomaticus minor muscle may have either a straight or a curved course along its length. It may attach to both the upper lip and the latera ... [...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 zygomat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Risorius
The risorius muscle is a muscle of facial expression. It arises from the fascia over the parotid gland, and inserts into the angle of the mouth. It is supplied by the facial nerve (CN VII). It may be absent or asymmetrical in some people. It retracts the angle of the mouth during smiling. Structure The risorius muscle arises in the fascia over the parotid gland. Passing horizontally forward, superficial to the platysma muscle, it inserts onto the skin at the angle of the mouth. It is a narrow bundle of fibers, broadest at its origin, but varies much in its size and form. It is superficial to the masseter muscle, partially covering it. Nerve supply Like all muscles of facial expression, the risorius is supplied by the facial nerve (CN VII). The specific branch is debated, with some sources giving marginal mandibular branch of the facial nerve and others giving buccal branch of the facial nerve. Development It has been suggested that the risorius muscle is only found in Homininae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depressor Anguli Oris Muscle
The depressor anguli oris muscle (triangularis muscle) is a facial muscle. It originates from the mandible and inserts into the angle of the mouth. It is associated with frowning, as it depresses the corner of the mouth. Structure The depressor anguli oris arises from the lateral surface of the mandible. Its fibres then converge. It is inserted by a narrow fasciculus into the angle of the mouth. At its origin, it is continuous with the platysma muscle, and at its insertion with the orbicularis oris muscle and risorius muscle. Some of its fibers are directly continuous with those of the levator anguli oris muscle, and others are occasionally found crossing from the muscle of one side to that of the other; these latter fibers constitute the transverse muscle of the chin. The depressor anguli oris muscle receives its blood supply from a branch of the facial artery. Nerve supply The depressor anguli oris muscle is supplied by the marginal mandibular branch of the facial nerve ... [...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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Auricular Muscle
The posterior auricular muscle is a muscle behind the auricle of the outer ear. It arises from the mastoid part of the temporal bone, and inserts into the lower part of the cranial surface of the auricle of the outer ear. It draws the auricle backwards, usually a very slight effect. Structure The posterior auricular muscle is found behind the auricle of the outer ear. It consists of two or three fleshy fasciculi. These arise from the mastoid part of the temporal bone by short aponeurotic fibers. They insert into the lower part of the cranial surface of the auricle of the outer ear. The posterior auricular muscle is supplied by branches of the posterior auricular artery, which continues deep to the muscle. It is drained by the posterior auricular vein that accompanies the artery. Nerve supply The posterior auricular muscle is supplied by the posterior auricular nerve, a branch of the facial nerve (VII). Function The posterior auricular nerve draws the auricle of the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Auricular Muscle
The superior auricular muscle is a muscle above the auricle of the outer ear. It originates from the epicranial aponeurosis, and inserts into the upper part of the medial surface of the auricle. It draws the auricle upwards. Structure The superior auricular muscle originates from the epicranial aponeurosis. Its fibres converge to be inserted by a thin, flattened tendon into the upper part of the medial surface of the auricle of the outer ear. It is the largest of the three auriculares muscles. It is thin and fan-shaped. Nerve supply The superior auricular muscle is supplied by the temporal branch of the facial nerve (VII). Additional images File:Auricularis superior.png, Auricula in context. Superior auricular shown in red. See also * Anterior auricular muscle * Posterior auricular muscle The posterior auricular muscle is a muscle behind the auricle of the outer ear. It arises from the mastoid part of the temporal bone, and inserts into the lower part of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |