Muscles of the face, lips and tongue

obicularis oris

a ring of muscle within the lips that forms a sphincter. contraction can result in several positional changes of the lips. These include movements of the lips toward one another and forward, can result in closure of the mouth and a forcing together of the lips. action may also fore the lips and/ or corners of the mouth against the teeth.

platysma

a very broad muscle that covers most of the front and side of the neck and much of the side of the face. contraction depresses the mandible, helps us open our mouth

zygomatic minor

angular muscle. contraction results in elevation of upper lip and also pulls the corner of the mouth upward. origin= zygomatic bone. insertion= lips

levator labii superioris

angular muscle. snarling muscle. contraction results in elevation of the upper lip and can also cause an outward turning of the upper lip.

zygomatic major

angular muscle; contraction pulls backward on the corner of the mouth.

levator labii superioris aleque nasi

angular musle. divides into a nasal segment and a lip segment. contraction causes elevation of the upper lip. contraction of the nasal segment dilate the anterior naris on the corresponding side.

temporalis

broad, fan-shaped, covers much of the side of the cranium. contraction results in an upward and backward pull on the mandible with vertical fibers pulling upward and horizontal fibers pulling backward. closes the jaw

superior longitudinal muslce

broad, flat, lies beneath the upper surface (dorsum) of the tongue. contraction can shorten the tongue and increase its convexity from front to back. intrinsic muscle

levator anguli oris

contraction draws the corner of the mouth upward and toward the side. deep to the zygomatics

geniohyoid

cylindrical muscle and lies above the mylohyoid. it can pull upward and forward on the hyoid bone and downward on the mandible. with fixation of the hyoid bone, contraction lowers the mandible and increases the distance between the jaws, similar to the function of the anterior belly of the digastric muscle. pulls mandible down.

palatoglossus

extrinsic muscle; originating from the lower surface of the palatal aponeurosis; when muscle contracts, it pulls upward and backward, and inward on the root of the tongue. dual purpose of depressing the soft palate or elevating the back of the tongue. the muscle can displace the tongue backward in the oral cavity and increases the concavity of its upper surface. when the left and right muscles contract, the result is a lengthwise grooving of the upper surface of the tongue.

genioglossus

extrinsic muscle; prime mover of the tongue; complex and makes up a large portion of the tongue. fan shaped and originates as three groups of fibers from the inner surface of the body of the mandible near the midline. collectively, the fibers travel through the body of the tongue between layers of the muslce fibers formed by the vertical transverse, and superior longitudinal muscles.

hyoglossus

extrinsic muscle; quadrilateral structure that originates from the upper border of the body and greater cornea of the hyoid bone and extends upward and forward to insert into the side of the tongue toward the rear. fibers intermingle with those of the styloglossus and palatoglossus muscles. contraction results in a lowering of the body of the tongue and a backward displacement of its mass. the lowering effect is most pronounced along the sides of the tongue.

styloglossus

extrinsic muscle; some fibers interdigitate with the fibers of the inferior longitudinal muscles while others interdigitate with fibers of the hyooglossus. contraction can; body of the tongue can be drawn upward and back, side of the tongue can be pulled upward to influence the structure's concavity, the tongue can be shortened, the tongue tip can be pulled toward the side.

massester

flat, quadrilateral and covers much of the outer surface of the ramus. outer layer courses along the front two-thirds of the zygomatic arch downward and backward to insert on the angle and the ramus. inner layer from the zygomatic arch downward and forward to insert into the upper half of the rams and its coronoid process. contraction results in elevation of the mandible and approximation of the mandible and maxilla.

transverse muscle

intrinsic muscle ;courses side to side; upper fibers fan out in upward; lower fibers fan out downward; intermingles with the fibers of other intrinsic and extrinsic tongue muscles. a major consituent of the bulk of the tongue; contraction narrows the tongue from side to side and elongation of the tongue. curling the tongue

vertical muscle

intrinsic muscle; originates beneath the dorsum of the tongue and courses downward vertically through the body of the tongue. contraction flattens the tongue on the side.

mentalis

lies on the front of the chin. contraction elevates and wrangles the chin. pulls lower lip out for pouting.

inferior longitudinal muscle

near the undersurface of the tongue and somewhat toward the side. contraction shortens the tongue and pulls the tip downward and toward the same side. simultaneous contraction pulls the tongue tip downward. intrinsic muscle

mylohyoid

positioned along the floor of the oral cavity. runs from the back of the chin to hyoid bone. mandibular depressor, pulls chin down.

medial pterygoid

quadrilateral structure. contraction results in elevation of mandible. sufficient elevation causes pressure to be place on the opposing teeth of the mandible and maxilla. has a special relationship with the masseter muscle. together they form a muscular sling that surrounds the angle of the mandible. result is a functional articulation between the mandible and maxilla

depressor labii inferioris

small, flat muscles located off the midline of the lower lip. contraction of the muscle pulls the lips down and out. Pouting Muscle

lateral pterygoid

smaller muscle of the mandible. contraction causes the condyle to slide downward and forward. contraction on only one side tends to move the front of the mandible toward the opposite side.

buccal cavity

the cavity or area located between the cheeks and gums or teeth

depressor anguli oris

the muscle is roughly triangular in form, contraction of the muscle pulls the corner of the mouth downward and also forces the lips together by drawing the upper lip downward against the lower lip.

risorius

the smiling muscle. transverse facial muscle. referred to as the "laughter muscle", small and located within the check but closer to the surface. contraction draws the corner of the mouth backward and toward the side and may force the lips against adjacent teeth.

buccinator

transverse facial muscle. known as the Bugler's muscle. uppermost fibers enter the upper lip, lowermost fibers enter the lower lip. central fibers on verge near the corner of the mouth and cross such. contraction can force the lips and cheek against the adjacent teeth moving food to the molars.

digastric

two- bellied arranged so that it can pull upward on the hyoid bone and/ or downward on the mandible. with greater relative fixation of the hyod bone, contraction of the anterior belly of this muscle results in lowering the the mandible which increases distance between the jaws. opens mandible and helps raise the hyoid bone