111 Ch. 30
Card Set Information
111 Ch. 30
Den 111 Ch. 30
all the muscles innervated by the 7th cranial nerve (facial nerve)
1) The muscles are more developed in animals then humans.
2) Posterior auricular muscle
* Pulls the ear back. Probably the best developed ear muscle.
3) Superior auricular muscle
* Raises the ear.
4) Anterior auricular muscle
* Pulls ear slightly forward.
1) Muscle- Occipitofrontalis (epicranius) is a paired muscle.
2) Forward movement causes a frown look.
3) Backward movement causes a surprise look.
1) Muscle- Platysma muscle.
2) There is some disagreement about its origin and insertion.
3) Inferior border of the mandible to just below the clavicle.
Has 3 muscles.
1) Orbicularis Oculi muscle (has 2 parts) (Closes the eyelids)
* Palpebral part (top) Eyelid.
* Orbital part (bottom).
2) Corrugators muscle (bridge of the nose to lateral part of the eyebrow)
* Pulls eyebrow medially and down. Ex. Frown
3) Procerus muscle (bridge of the nose to medial end of the eyebrow)
* Pulls eyebrow at medial end down. Ex. Frown or Squint
Has 2 muscles.
1) Dilator Naris
* Pulls down on nostrils. Ex. Flare and Dilate
2) Compressor Naris
* Causes nostrils to close or compress.
* Aids in mastication
2) Abnormal pressure causes:
* Cheek biting
* Lip biting
* Lip compression (can cause teeth misalignment)
Muscle of the Mouth (10)
1) Orbicularis Oris
* Circles the oral cavity in the tissue of the lip.
* Causes �closes and compresses lip�.
2) Levator Labii Superioris
* Elevates the upper lip.
* Origin is just beneath the lower rim of the orbit.
* Insert into the Orbicularis oris.
3) Zygomaticus Minor
* Elevates upper lip.
* Poorly developed muscle.
* From the Zygomatic bone to the Orbicularis oris.
4) Zygomaticus Major
* It is larger then the zygomatius minor.
* Elevates the corner of the mouth as in a smile.
* From the Zygomatic bone to the Orbicularis oris5)
5) Levator Anguli
* Pulls the angles of the mouth up and toward the midline.
* From the maxilla(below the infra orbital foramen) to the Orbicularis oris.
* Lies deep to the levator labii superioris and the zygomaticus major and minor.
6) Depressor Labii Inferioris
* Pulls lower lip down as in a pout.
* From beneath the angles of the mouth to just below the inferior boarder of the mandible.
7) Depressor Anguli Oris
* Pulls the corners of the mouth down.
* The muscle fibers appear to be a continuation of the fibers of the Platysma.
* Pulls skin of chin up
* Probably the most important muscle of the mouth.
* Involved in
: 1) Facial expression 2) Mastication
* When the muscle contracts, it pulls the corners of the mouth back and compresses the cheeks.
* During chewing, the food is crushed and grounded between the molars.
* Also referred to the accessory muscle of mastication.
* Fibers run anteriorly.
* Person with a stroke or Bell's palsy would have difficultly chewing, food would pile up in the buccal vestibule.
* Aids in smiling, but poorly developed.
* Is a small muscle.
* Inserts into the corner of the mouth.
* Is an apparent continuation of the posterior fibers of the Platysma muscle.