Muscles of facial expression
risorius muscle
Origin: Connective tissue (fascia) over the parotid gland Inserts: onto the corner of the mouth Function: Pulls the corner of the mouth laterally
Platysma Muscle
Origin: Fascia of the pectoralis muscle - Insertion: Corner of the mouth, lower border of the mandible and the muscles surrounding the mouth Action: Raises the skin of the neck to form noticeable vertical and horizontal ridges and depressions.Can also can pull the corner of the mouth down, as when a person grimaces
Levator labii superioris alaeque nasi
Origin: Frontal process of maxilla - Insertion: Upper lip and ala of the nose - Action: Elevates the ala of the nose and upper lip, dilating the nostrils, as in a sneering expression
Levator labii superioris
Origin: Lower rim of orbit Insertion: Upper lip Action: Elevates the upper lip
Zygomaticus major muscle
Origin:Zygomatic bone Inserts: onto the angle of the mouth Function: Elevates the corners of the mouth as in smiling
Palpebral commisures
Point of attachment of the upper eyelid to the lower eyelids. Fissure is bound medially and laterally by this.
Risorius muscle widens the oral cavity and
Produces more of a grimace than a grin.
Palpebrae or eyelids
Protects the eyeballs anteriorly
pterygomandibular raphe
-is noted in the oral cavity as the pterygomandibular fold.Extends from the hamulus and passes inferiorly to attach to the posterior end of the mandible's mylohyoid line.
Muscles of the mouth
Levator labii superioris, Zygomaticus major, Zygomaticus minor, Levator anguli oris,Depressor anguli oris, Mentalis, Platysma, Orbicularis oris, Buccinator, Risorius
Depressor labii inferioris
Located deep to the depressor anguli oris Origin: Border of the mandible - Insertion: Medial to the corner of the mouth - Action: Pulls down on lower lip exposing the mandibular incisor teeth
muscles of facial expression are
superficial on the face.
The bellies(occipitalis and frontalis muscles) are separated by?
a large, spread-out scalpal tendon.
What muscle of the eye works in concert with the muscles of the nasal region
corrugator supercilii muscle
Patient's inability to wrinkle his or her forehead is an example of
damage to facial nerve
nasolabial groove
furrow that separates the upper lip and nose from the cheek is called the nasolabial groove
Zygomaticus major muscle contracts together with the orbicularis oculi muscle to form a :
genuine smile
Labiomental groove
horizontal furrow between the lower lip and chin
Forehead furrows
horizontal wrinkles in the skin
Levator anguli oris muscle
inserted onto, and elevates the corners of the mouth
labial commissures
joins the upper and lower lip
Three muscles that function to raise the upper lip
levator labii superioris alaeque nasi muscle, levator labii superioris muscle, zygomaticus minor muscle
mental protuberance
portion of the chin that juts forward and is related to the shape of the chin mentum
zygomatic eminence
prominence of the cheek wall just inferior to the rim of the orbit
Palpebral fissure
space between the margins of the eyelids when they are open
Origin
the end of the muscle attached to the LEAST movable structure- stationary
Insertion
the end of the muscle attached to the MORE movable structure
The insertion point of a muscle moves toward
the origin during muscle movement
Muscles of the eyes
Corrugator supercilii, Orbicularis oculi, Procerus muscle
Nasolabial grooves relevance to the hygienist
During facial paralysis, the groove is greatly reduced or absent, thus comparing the depth of the groove on the left versus the right side of the face can indicate damages to branches of the facial nerve, which is a cranial nerve.
Procerus muscle
Origin: Nose - Insertion: Skin medial to eyebrow - Action: Moves eyebrows downward and medially; - Causes horizontal wrinkles of skin of the bridge of the nose
Occipital/occipitalis muscle
Origin: Occipital bone and mastoid process of the temporal bone Insertion: In the epicranial aponeurosis Function: Creates horizontal wrinkles, makes up the occipitofrontalis(aka epicranius muscle)
Corrugator supercilii muscle
Origin: Superciliary ridge - Insertion: Bridge of nose - Action: Pulls eyebrows medially; vertical wrinkles between eyebrows Draws the skin tissue of the eyebrow medially and inferiorly toward the nose. Causes vertical wrinkles in the glabella area of the forehead and horizontal wrinkles at the bridge of the nose, as when a person frowns.
Zygomaticus minor muscle
Origin: Zygomatic bone Inserts: Upper lip Function: elevates the upper lip, assisting in smiling
Facial nerve (VII)
The innervation for the muscles of facial expression.
Bridge of the nose
formed by the fusion of the nasal bones, is the narrow part of the nose leading downward between the eyes toward the lower, flared part surrounding the nostrils(openings into the nasal cavities)
Mentalis muscle fibers
when active,may dislodge a complete denture in an edentulous patient who has lost alveolar ridge height.
Muscles that merge with the orbicularis oris muscle superior and medial to the insertion of zygomaticus major muscle
zygomaticus minor, the levator labii superioris, levator labii superioris alaque nasi muscles
Muscles of the nose and ears are generally
not a concern to the hygienist
Two bellies of epicranial muscle are
occipitalis muscle and frontalis muscle
Muscles of the scalp
occipitofrontalis/epicranius, occipitalis muscle
The epicranial aponeurosis is located
over the area where the parietal and occipital bones meet, the most superior portion of the skull.
Orbicularis oris (movements)
1. pressing together (closing the lips) 2. tightening and thinning (pursing the lips) 3. rolling inwards between the teeth (grimacing) 4. thrusting outwards (pouting and kissing).
Labial tubercle
A central rounded projection on the upper lip
Superior, middle, and inferior auricular muscles
Action: Rudimentary movements of the ear Summary O The muscles of
Nasalis muscle
Action: Opens and closes nostrils
Muscles of the nose and ears
Nasalis muscle
This muscle and its tendon are one of the layers that form the scalp, what muscle is it?
Epicranial
How can changes in facial expression can be used to diagnose facial nerve palsies?
Facial Palsies, which are the paralysis of facial muscles by injury or disease to the facial nerve, cause distorted facial features.
Why is facial Palsies of clinical interest to the hygienist?
Improper closure of the mouth may cause drooling from the mouth and the potential of biting on the cheek wall
columella nasi
In between the nostrils, represents the fleshy distal margin of the nasal septum
Orbicularis oculi
Orbital portion encircles eye - Palpebral portion in eyelids - Action:Muscle closes the eyelid. If all the fibers are active, the eye can be squinted, and wrinkles from in the lateral portions of the eye ("crow's feet")
Two parts of the orbicularis oculi muscle:
Orbital portion- surrounds the eye Palpebral portion- found in the eye
Depressor anguli oris
Origin: Border of the mandible - Insertion: Corner of the mouth - Action: Pulls corner downward
Frontalis/frontal muscle
Origin: the epicranial aponeurosis, or galea aponeurotica, a scalpal tendon. Insertion: Into the skin tissue of the eyebrow and root of the nose. Function: Creates horizontal wrinkles, makes up the occipitofrontalis(aka epicranius muscle)
Epicranial Muscle
Raises the eyebrows and scalp- "surprise!"
Buccinator muscle
Runs horizontally - Forms the anterior portion of the cheek or the lateral wall of the oral cavity. - Origin: Pterygomandibular raphe - Insertion: Mandible and maxilla - Action: Tightens cheek wall; assists in chewing by keeping food in the mouth
Mentalis Muscle
Short, thick muscle superior and medial to the mental nerve in the mouth region. - Origin: Mandible below lateral incisors - Insertion: Skin of the chin - Action: Pushes up the lower lip and wrinkles skin of the chin.It raises the chin, causing the displaced lower lip to protrude and narrowing the oral vestibule.
Occipitalis and frontalis (bellies) muscle can:
act independently of each other in facial expression
Supraciliary ridge
bony prominence above (superior to)the eyebrows
Philtrum
just inferior to the columella. Is a vertical groove that characterizes the upper lip. Because it represents the fusion site for two embryonic structures that form the upper lip, it is a site for cleft lips.
orbicularis oris muscle
surrounds the opening of the mouth and is the main intrinsic muscle of the lips
The buccinator and superior pharyngeal constrictor muscles of the pharynx are attached to each other at
the pterygomandibular raphe
Orbicularis oris in the upper lip, fibers also insert on:
the ridges of the philtrum
Nasal ala
the wing of the nose, which is the flaring cartilaginous expansion that forms the outer surface of each nostril