Mentalis

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Mentalis
Mentalis.png
Muscles of the head, face, and neck.
Details
Origin anterior mandible
Insertion chin
Nerve mandibular branch of facial nerve
Actions elevates and wrinkles skin of chin, protrudes lower lip
Identifiers
Latin musculus mentalis
TA98 A04.1.03.037
TA2 2087
FMA 46825
Anatomical terms of muscle

The mentalis muscle is a paired central muscle of the lower lip, situated at the tip of the chin. [1] It originates from the mentum of the mandible, and inserts into the soft tissue of the chin. It is sometimes referred to as the "pouting muscle" due to it raising the lower lip and causing chin wrinkles.

Contents

Structure

The mentalis muscle originates from the mental protuberance of the mandible near the midline. [2] [3] It inserts into the soft tissue and skin of the chin. [2] [3]

Function

The mentalis muscle causes a weak upward-inward movement of the soft tissue complex of the chin. [2] This raises the central portion of the lower lip. [2] In the setting of lip incompetence (the upper and lower lips do not touch each other at rest), the mentalis muscle contraction can bring temporary but strained oral competence.

In conjunction with the orbicularis oris muscle (for the upper lip), the mentalis muscle allows the lips to "pout". Externally, the mentalis muscle contraction causes wrinkling and dimpling of the skin on the chin, as used in expressions of doubt or displeasure. [4]

Clinical significance

The mentalis muscle can be easily assessed using ultrasound. [5]

Geniospasm

Geniospasm is a genetic movement disorder of the mentalis muscle. [6] It involves repetitive contraction of the muscle, with episodes lasting between seconds and hours. [6] Certain medications may be used to treat it, such as haloperidol and benzodiazepines. [6] Injection of botulinum toxin (permanently paralysing the muscle) may be more effective. [6]

Cosmetics

The mentalis muscle may be partially paralysed using botulinum toxin to reduce wrinkling of the skin of the chin. [4] This may be done for cosmetic purposes. [4]

Additional images

Related Research Articles

<span class="mw-page-title-main">Botulinum toxin</span> Neurotoxic protein produced by Clostridium botulinum

Botulinum toxin, or botulinum neurotoxin (BoNT), is a neurotoxic protein produced by the bacterium Clostridium botulinum and related species. It prevents the release of the neurotransmitter acetylcholine from axon endings at the neuromuscular junction, thus causing flaccid paralysis. The toxin causes the disease botulism. The toxin is also used commercially for medical and cosmetic purposes.

<span class="mw-page-title-main">Torticollis</span> Medical condition

Torticollis, also known as wry neck, is a dystonic condition defined by an abnormal, asymmetrical head or neck position, which may be due to a variety of causes. The term torticollis is derived from the Latin words tortus, meaning "twisted" and collum, meaning "neck."

<span class="mw-page-title-main">Cremaster muscle</span> Muscle covering the testis and spermatic cord

The cremaster muscle is a paired structure made of thin layers of striated and smooth muscle that covers the testis and the spermatic cord in human males. It consists of the lateral and medial parts. Cremaster is an involuntary muscle, responsible for the cremasteric reflex; a protective and physiologic superficial reflex of the testicles. The reflex raises and lowers the testicles in order to keep them protected. Along with the dartos muscle of the scrotum, it regulates testicular temperature, thus aiding the process of spermatogenesis.

<span class="mw-page-title-main">Wrinkle</span> Crease on otherwise smooth surface

A wrinkle, also known as a rhytid, is a fold, ridge or crease in an otherwise smooth surface, such as on skin or fabric. Skin wrinkles typically appear as a result of ageing processes such as glycation, habitual sleeping positions, loss of body mass, sun damage, or temporarily, as the result of prolonged immersion in water. Age wrinkling in the skin is promoted by habitual facial expressions, aging, sun damage, smoking, poor hydration, and various other factors. In humans, it can also be prevented to some degree by avoiding excessive solar exposure and through diet.

<span class="mw-page-title-main">Rhytidectomy</span> Type of cosmetic surgery

A facelift, technically known as a rhytidectomy, is a type of cosmetic surgery procedure used to give a more youthful facial appearance. There are multiple surgical techniques and exercise routines. Surgery usually involves the removal of excess facial skin, with or without the tightening of underlying tissues, and the redraping of the skin on the patient's face and neck. Exercise routines tone underlying facial muscles without surgery. Surgical facelifts are effectively combined with eyelid surgery (blepharoplasty) and other facial procedures and are typically performed under general anesthesia or deep twilight sleep.

Chin augmentation using surgical implants can alter the underlying structure of the face, providing better balance to the facial features. The specific medical terms mentoplasty and genioplasty are used to refer to the reduction and addition of material to a patient's chin. This can take the form of chin height reduction or chin rounding by osteotomy, or chin augmentation using implants. Improving the facial balance is commonly performed by enhancing the chin using an implant inserted through the mouth. The goal is to provide a suitable projection of the chin as well as the correct height of the chin which is in balance with the other facial features.

Hemifacial spasm (HFS) is a rare neuromuscular disease characterized by irregular, involuntary muscle contractions (spasms) on one side (hemi-) of the face (-facial). The facial muscles are controlled by the facial nerve, which originates at the brainstem and exits the skull below the ear where it separates into five main branches.

<span class="mw-page-title-main">Cricothyroid muscle</span>

The cricothyroid muscle is the only tensor muscle of the larynx aiding with phonation. It is innervated by the superior laryngeal nerve. Its action tilts the thyroid forward to help tense the vocal cords.

<span class="mw-page-title-main">Platysma muscle</span> Human neck muscle

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.

<span class="mw-page-title-main">Corrugator supercilii muscle</span> Muscle near the eye

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.

<span class="mw-page-title-main">Spasmodic torticollis</span> Medical condition

Spasmodic torticollis is an extremely painful chronic neurological movement disorder causing the neck to involuntarily turn to the left, right, upwards, and/or downwards. The condition is also referred to as "cervical dystonia". Both agonist and antagonist muscles contract simultaneously during dystonic movement. Causes of the disorder are predominantly idiopathic. A small number of patients develop the disorder as a result of another disorder or disease. Most patients first experience symptoms midlife. The most common treatment for spasmodic torticollis is the use of botulinum toxin type A.

<span class="mw-page-title-main">Meige's syndrome</span> Medical condition

Meige's syndrome is a type of dystonia. It is also known as Brueghel's syndrome and oral facial dystonia. It is actually a combination of two forms of dystonia, blepharospasm and oromandibular dystonia (OMD).

<span class="mw-page-title-main">Mental nerve</span> Sensory nerve of the face

The mental nerve is a sensory nerve of the face. It is a branch of the posterior trunk of the inferior alveolar nerve, itself a branch of the mandibular nerve (CN V3), itself a branch of the trigeminal nerve (CN V). It provides sensation to the front of the chin and the lower lip, as well as the gums of the anterior mandibular (lower) teeth. It can be blocked with local anaesthesia for procedures on the chin, lower lip, and mucous membrane of the inner cheek. Problems with the nerve cause chin numbness.

<span class="mw-page-title-main">Marginal mandibular branch of the facial nerve</span>

The marginal mandibular branch of the facial nerve passes forward beneath the platysma and depressor anguli oris, supplying the muscles of the lower lip and chin, and communicating with the mental branch of the inferior alveolar nerve.

Synkinesis is a neurological symptom in which a voluntary muscle movement causes the simultaneous involuntary contraction of other muscles. An example might be smiling inducing an involuntary contraction of the eye muscles, causing a person to squint when smiling. Facial and extraocular muscles are affected most often; in rare cases, a person's hands might perform mirror movements.

Jaw reduction or mandible angle reduction is a type of surgery to narrow the lower one-third of the face—particularly the contribution from the mandible and its muscular attachments. There are several techniques for treatment—including surgical and non-surgical methods. A square lower jaw can be considered a masculine trait, especially in Asian countries. As a result, whereas square lower jaws are often considered a positive trait in men, a wide mandible can be perceived as discordant or masculine on women, or sometimes in certain men, particularly when there is asymmetry.

<span class="mw-page-title-main">Geniospasm</span> Medical condition

Geniospasm is movement disorder of the mentalis muscle.

<span class="mw-page-title-main">Photoaging</span> Ultraviolet light-induced biological development over time

Photoaging or photoageing is a term used for the characteristic changes to skin induced by chronic UVA and UVB exposure. Tretinoin is the best studied retinoid in the treatment of photoaging.

Injectable filler is a soft tissue filler injected into the skin at different depths to help fill in facial wrinkles, provide facial volume, and augment facial features: restoring a smoother appearance. Most of these wrinkle fillers are temporary because they are eventually absorbed by the body. Most dermal fillers today consist of hyaluronic acid, a naturally occurring polysaccharide that is present in skin and cartilage. Some people may need more than one injection to achieve the wrinkle-smoothing effect. The effect lasts for about six months or longer. Successful results depend on health of the skin, skill of the health care provider, and type of filler used. Regardless of material filler duration is highly dependent on amount of activity in the region where it is injected. Exercise and high intensity activities such as manual labor can stimulate blood flow and shorten the lifespan of fillers.

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References

  1. Lips and Perioral Region Anatomy at eMedicine
  2. 1 2 3 4 Hussain, G.; Manktelow, R.T; Tomat, L.R (2004-09-01). "Depressor labii inferioris resection: an effective treatment for marginal mandibular nerve paralysis". British Journal of Plastic Surgery. 57 (6): 502–510. doi:10.1016/j.bjps.2004.04.003. ISSN   0007-1226. PMID   15308395.
  3. 1 2 Zide, Barry M. (March 2000). "The Mentalis Muscle: An Essential Component of Chin and Lower Lip Position". Plastic and Reconstructive Surgery . 105 (3): 1213–1215. doi:10.1097/00006534-200003000-00061. ISSN   0032-1052. PMID   10724283.
  4. 1 2 3 Glaser, Dee Anna (2009). "26 - Botulinum Neurotoxin for Dermatologic and Cosmetic Disorders". Botulinum toxin: therapeutic clinical practice and science. Philadelphia: Saunders. pp. 324–338. doi:10.1016/B978-1-4160-4928-9.00026-3. ISBN   978-1-4377-1119-6. OCLC   460883288.
  5. Volk, Gerd Fabian; Wystub, Nadja; Pohlmann, Martin; Finkensieper, Mira; Chalmers, Heather J.; Guntinas-Lichius, Orlando (2013). "Quantitative ultrasonography of facial muscles". Muscle & Nerve. 47 (6): 878–883. doi:10.1002/mus.23693. ISSN   1097-4598. PMID   23519888. S2CID   39807522.
  6. 1 2 3 4 Deuschl, Günther; Fasano, Alfonso (2009). "29 - Essential Tremor and Other Tremors". Movement Disorders 4 (1st ed.). Philadelphia: Saunders / Elsevier. pp. 506–557. doi:10.1016/B978-1-4160-6641-5.00029-5. ISBN   978-1-4160-6641-5. OCLC   460904302.