Muscles

Human muscle system, the muscles of the human body that work the skeletal system including the jaw muscles
Human muscle system, the muscles of the human body that work the skeletal system including the jaw muscles

The human muscular system is responsible for tasks involving the movement of the human body.

There are around 650 skeletal muscles within the typical human body. The muscles that operate the human body can be categorized into a number of groups which include muscles relating to the head and neck functions, muscles of the torso or trunk, muscles of the upper limbs, and then, the group of muscles that work a person’s lower limbs.

Muscle is a soft tissue found in most animals and humans. Its cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion – and those that operate a person’s jaw have remarkable power. They are primarily responsible for maintaining and changing posture, locomotion, as well as movements of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis. Such fibrous tissues are derived from the mesodermal layer of embryonic germ cells in a process known as myogenesis.

Basic Types of Human Muscular Components

There are three types of muscle, skeletal or striated, cardiac, and smooth. A person’s stamina or action can be classified as being either voluntary or involuntary. Cardiac and smooth muscles contract without conscious thought and are termed involuntary, whereas the skeletal ones contract upon command. Skeletal ligaments in turn can be divided into fast and slow-twitch fibers. They are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast-twitch fibers. These chemical reactions produce adenosine triphosphate (ATP) molecules that are used to power the movement of the myosin heads. The term muscle is derived from the Latin musculus meaning “little mouse” perhaps because of the shape of certain muscles or because when contracting them, they look like mice moving under the skin.

Mouth Muslces

The following table explaining the mouth’s muscles comes from Wikipedia:

Muscle Origin Insertion Artery Nerve Action Antagonist
levator anguli oris
(caninus)
maxilla modiolus of mouth facial artery facial nerve [CNVII] elevates angle of mouth (smile)
depressor anguli oris
(triangularis)
tubercle of mandible mandibular branch of facial nerve [CNVII] depresses angle of mouth (frown)
levator labii superioris medial part of infra-orbital margin of maxilla skin and muscle of upper lip (labii superioris) superior labial artery buccal branch of facial nerve [CNVII] elevates upper lip
depressor labii inferioris oblique line of mandible, between symphysis and mental foramen integument of lower lip, orbicularis oris fibers, its fellow of opposite side inferior labial artery facial nerve [CNVII] depresses lower lip
mentalis alveolar yoke of lower, lateral incisor tooth, found on anterior mandible skin of chin mandibular branch of facial nerve [CNVII] elevates and wrinkles skin of chin, protrudes lower lip
buccinator alveolar processes of maxilla and mandible, pterygomandibular raphe fibres of orbicularis oris buccal artery buccal branch of facial nerve [CNVII] compress cheeks against teeth (blowing), mastication
orbicularis oris maxilla and mandible skin around lips superior labial artery, inferior labial artery puckers lips
risorius parotid fascia modiolus of mouth facial artery draw back angle of mouth
Zygomatic muscles
     major zygomatic bone in region of zygomaticomaxillary suture modiolus of mouth facial artery buccal branch of facial nerve [CNVII] draws angle of mouth upward and laterally
     minor skin of upper lip elevates upper lip

What Muscles are in a Person’s Jaw?

The jaw movements are a complex and marvelous three-dimensional manner during jaw movements. There are three jaw-closing muscles that work in harmony (masseter, temporalis, and medial pterygoid) and two jaw-opening muscles (lateral pterygoid and digastric). The basic functional unit of the jaw muscle is the motor unit. The treatment of jaw sprain and strain is known as JAMSS.