Muscles of Facial Expression

Muscles Covered Scalp: Eye: Nose: Occipitofrontalis Temporoparietalis Auricularis group Eye: Orbicularis oculi Levator palpebrae superioris Corrugator supercilii Nose: Procerus Nasalis Depressor septi nasi ● How are the muscles of facial expression organized? Into four major groups: facial expression muscles of the scalp, the eye, the nose, and the mouth 2

Muscles Covered (cont’d.) Mouth: Levator labii superioris alaeque nasi Levator labii superioris Zygomaticus minor Zygomaticus major Levator anguli oris Risorius Depressor anguli oris Depressor labii inferioris Mentalis Buccinator Orbicularis oris Platysma 3

Superficial Right Lateral View of the Muscles of the Head Note the muscles of the scalp and the galea aponeurotica, considered part of the occipitofrontalis. ●

Superficial and Intermediate Anterior Views of the Muscles of the Head Note now many muscles attach from the mouth upward and how many attach from the mouth downward. It actually does NOT take more muscles to frown than to smile.  ●

Superficial Posterior View of the Muscles of the Head ● Note the occipitalis belly of the occipitofrontalis. The occipitofrontalis is often involved with tension headaches.

Facial Landmarks— Anterior Views ● The modiolus is a condensation of fascia just lateral to the angle (corner) of the mouth that serves as a site of attachment for 6 muscles of facial expression.

Facial Landmarks (cont’d.)— Anterolateral and Lateral Views ● Much of the nose is cartilage.

SCALP Scalp: Occipitofrontalis Temporoparietalis Auricularis group

Occipitofrontalis Expression of elevating the eyebrows by the occipitofrontalis ●

Occipitofrontalis: Attachments OCCIPITALIS BELLY Origin: The lateral 2/3 of the highest nuchal line of the occipital bone and the mastoid area of the temporal bone Insertion: Galea aponeurotica Nerve: Posterior Auricular branch of the Facial Nerve FRONTALIS BELLY Fascia and skin overlying the frontal bone Temporal Branch of the Facial Nerve ● Which attachment is more likely to move? The anterior attachment is more likely to move.

Occipitofrontalis: Action Draws the scalp posteriorly (elevation of the eyebrow) Draws the scalp anteriorly If this muscle contracts, how would the anterior attachment move? It would move posteriorly, drawing the scalp posteriorly. This would elevate the eyebrow. ●

Occipitofrontalis: Review— Lateral View The occipitofrontalis is superficial.

Temporoparietalis— Lateral View ● What does the name “temporoparietalis” tell us? It tells us that this muscle lies over the temporal and parietal bones.

Temporoparietalis: Attachments Origin: Fascia superior to the ear Insertion: Lateral border of the galea aponeurotica Nerve: The Temporal Branch of the Facial Nerve ● Which attachment is more mobile? The attachment into the fascia superior to the ear is more mobile.

Temporoparietalis: Action Elevates the ear Tightens the Scalp When this muscle contracts, how does the ear move? It moves superiorly, elevating the ear. Some people are not able to engage the temporoparietalis muscle. The degree of development of the temporoparietalis varies; it is very thin for some individuals, and it is nonexistent for others.

Temporoparietalis: Review— Lateral View The temporoparietalis is superficial. ●

Auricularis Anterior, Superior, and Posterior—Lateral View ● What does the name “auricularis” tell us? It tells us that these muscles are involved in the movement of the ear.

Auricularis Anterior: Attachments Origin: The lateral margin of the Galea aponeurotica Insertion: The spine of the helix of the Anterior ear Nerve: The Temporal Branch of the Facial Nerve ● Which attachment is generally more mobile? The ear is generally more mobile.

Auricularis Superior: Attachments Origin: The lateral margin of the Galea aponeurotica Insertion: The superior surface of the cranial surface of the superior ear Nerve: The Temporal Branch of the Facial Nerve ● Which attachment is generally more mobile? The ear is generally more mobile.

Auricularis Posterior: Attachments Origin: The mastoid area of the temporal bone Insertion: The ponticulus of the eminentia conchae of the posterior ear Nerve: The Posterior Auricular Branch of the Facial Nerve ● Which attachment is more mobile? The ear is more mobile.

Auricularis Anterior, Superior, and Posterior: Actions Auricularis anterior: Draws the ear anteriorly Auricularis superior: Elevates the ear Auricularis posterior: Draws the ear posteriorly Auricularis anterior and superior: Tightens and moves the scalp ● Which direction would the auricularis anterior move the ear when it contracts? It would move the ear anteriorly. ● Which direction would the auricularis superior move the ear when it contracts? It would move the ear superiorly, elevating the ear. ● Which direction would the auricularis posterior move the ear when it contracts? It would move the ear posteriorly.

Auricularis Group: Review— Lateral View ● The auricularis muscles are superficial.

EYE Eye: Orbicularis oculi Levator palpebrae superioris Corrugator supercilii

Orbicularis Oculi—Anterior View ● What does the name “orbicularis oculi” tell us? It tells us that this muscle encircles the eye.

Orbicularis Oculi (cont’d.)—Anterolateral View Expression created by the orbicularis oculi ●

Orbicularis Oculi: Attachments Origin: The Medial side of the eye ORBITAL PART: the nasal part of the frontal bone, the frontal process of the maxilla, and the medial palpebral ligament PALPEBRAL PART: the medial palpebral ligament LACRIMAL PART: the lacrimal bone Insertion: Medial side of the eye (returns to the same attachment, encircling the eye) ORBITAL PART: returns to the same attachment, these fibers encircle the eye PALPEBRAL PART: the lateral palpebral ligament (these fibers run through the connective tissue of the eyelids) LACRIMAL PART: the medial palpebral raphe (these fibers are deeper in the eye socket) Nerve: The Temporal and Zygomatic branches of the Facial Nerve ● The orbicularis oculi is a sphincter muscle.

Orbicularis Oculi: Actions Closes and squints the eye (orbital part) Depresses the upper eyelid (palpebral) Elevates the lower eyelid (palpebral) Retraction of the lower eyelid (lacrimal) Assists in tear transport and drainage (lacrimal) ●

Orbicularis Oculi: Actions When a linear muscle shortens (contracts), its length decreases. When the same linear muscle is arranged in a circular fashion and shortens (contracts), its length again decreases; this means that the length of the line available to draw the circle decreases, so the size (diameter) of the circle lessens. This means that the orbital part of the orbicularis oculi, which is a sphincter muscle, closes and squints the eye. ●

Orbicularis Oculi: Review— Anterior View The orbicularis oculi surrounds the eye and is superficial. ●

Levator Palpebrae Superioris—Lateral View ● What does the name “levator palpebrae superioris” tell us? It tells us that this muscle elevates the upper eyelid.

Levator Palpebrae Superioris (cont’d.)—Anterolateral View ● Which part of the muscle name indicates that the eyelid will be elevated? “Levator” means lifter in Latin, so “levator” indicates that the eyelid will be elevated.

Levator Palpebrae Superioris (cont’d)—Anterior View Expression created by the levator palpebrae superioris ●

Levator Palpebrae Superioris: Attachments Origin: The anterior surface of the lesser wing of the sphenoid bone Insertion: The fascia and skin of the upper eyelid Nerve: The Oculomotor Nerve (CN 3) ● Which attachment is more mobile? The upper eyelid is more mobile.

Levator Palpebrae Superioris: Action Elevates the upper eyelid If the muscle contracted, and the upper eyelid moved, which way would it move? The upper eyelid would move up toward the sphenoid bone. ●

Levator Palpebrae Superioris: Review—Anterior View The levator palpebrae superioris is deep to the orbicularis oculi in the upper eyelid. ●

Corrugator Supercilii— Anterior View ● What does the name “corrugator supercilii” tell us? It tells us that this muscle wrinkles the skin of the eyebrow.

Corrugator Supercilii (cont’d.) Expression created by the corrugator supercilii ●

Corrugator Supercilii: Attachments Origin: The medial end of the superciliary arch on the inferior part of the frontal bone Insertion: Fascia and skin deep to the eyebrow Nerve: The Temporal Branch of the Facial Nerve ● Which attachment is more mobile? The attachment of the skin deep to the eyebrow is more mobile.

Corrugator Supercilii: Action Draws the eyebrow inferomedially If the muscle contracted, and the skin deep to the eyebrow moved, which way would it move? The skin deep to the eyebrow would move down toward the frontal bone, drawing the eyebrow inferiorly and medially. ●

Corrugator Supercilii: Review—Anterior View The corrugator supercilii is deep to the frontalis. ●

NOSE Nose: Procerus Nasalis Depressor septi nasi

Procerus—Anterior View ● What does the name “procerus” tell us? It tells us that this muscle helps to create the expression of a prince.

Procerus (cont’d.)—Anterior View Expression created by the procerus ●

Procerus: Attachments Origin: Fascia and skin over the nasal bone Insertion: Fascia and skin medial to the eyebrow Nerve: The Superior Buccal Branches of the Facial Nerve

Procerus: Actions Wrinkles the skin of the nose upward Draws down the medial eyebrow If the muscle contracted, and the skin of the nose was pulled upward toward the eyebrow, which way would it move? It would move upwards, wrinkling the skin of the nose. If the muscle contracted, and the skin and fascia of the eyebrow were pulled toward the nose, which way would it move? It would move down toward the nose, drawing down the medial eyebrow. ●

Procerus: Review— Anterior View The procerus is located at the top of the nose.

Nasalis—Anterior View ● What does the name “nasalis” tell us? It tells us that this muscle is involved in moving the nose.

Nasalis (cont’d.)—Anterior View Expression created by the alar part of the nasalis ●

Nasalis: Attachments Origin: The Maxilla THE TRANSVERESE PART: The maxilla lateral to the upper part of the nose THE ALAR PART: The maxilla lateral to the lower part of the nose Insertion: Cartilage of the nose and the opposite side Nasalis Muscle The opposite side nasalis muscle over the upper cartilage of the nose The alar cartilage of the nose Nerve: The Superior Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The nose attachment is more mobile.

Nasalis: Actions Flares the nostril (alar part) Constricts the nostril (transverse part) The lower (alar) part flares the nostril, whereas the upper (transverse) part of the nasalis constricts the nostril. ●

Nasalis: Review—Anterior View The nasalis is located over the nose.

Depressor Septi Nasi— Anterior View ● What does the name “depressor septi nasi” tell us? It tells us that this muscle depresses the nasal septum.

Depressor Septi Nasi (cont’d.)—Anterior View Expression created by the depressor septi nasi ●

Depressor Septi Nasi: Attachments Origin: The incisive fossa of the maxilla Insertion: The septum and the alar cartilage of the nose Nerve: The Superior Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The nose attachment is more mobile.

Depressor Septi Nasi: Action Constricts the nostril If the muscle contracted, and the tissue of the nose were pulled toward the maxillary attachment, which way would it move? The tissue of the nose would move inferiorly toward the maxilla, constricting the nostril. ●

Depressor Septi Nasi: Review—Anterior View The depressor septi nasi is located inferior to the nose. ●

MOUTH Mouth: Levator labii superioris alaeque nasi Zygomaticus minor Zygomaticus major Levator anguli oris Risorius Depressor anguli oris Depressor labii inferioris Mentalis Buccinator Orbicularis oris Platysma 58

Levator Labii Superioris Alaeque Nasi—Anterior View ● What does the name “levator labii superioris alaeque nasi” tell us? It tells us that this muscle elevates the upper lip and is involved with the cartilages (alae) of the nose.

Levator Labii Superioris Alaeque Nasi (cont’d.)—Anterior View Expression created by the levator labii superioris alaeque nasi ●

Levator Labii Superioris Alaeque Nasi: Attachments Origin: The frontal process of the maxilla near the nasal bone Insertion: LATERAL SLIP: the muscular substance of the lateral part of the upper lip MEDIAL SLIP: the alar cartilage and the fascia and skin of the nose Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The inferior (nose and upper lip) attachment is more mobile.

Levator Labii Superioris Alaeque Nasi: Actions Elevates the upper lip Flares the nostril Everts the upper lip If the upper lip were to be pulled toward the maxillary bone attachment, which way would it move? The upper lip would move up toward the maxillary bone, elevating the upper lip. If the nose were to be pulled toward the maxillary bone attachment, which way would it move? The nose would move up toward the maxillary bone, flaring the nostril. ●

Levator Labii Superioris Alaeque Nasi: Review—Anterior View The levator labii superioris alaeque nasi is located between the nasalis and the levator labii superioris.

Levator Labii Superioris—Anterior View ● What does the name “levator labii superioris” tell us? It tells us that this muscle elevates the upper lip.

Levator Labii Superioris (cont’d.)—Anterior View Expression created by the levator labii superioris

Levator Labii Superioris: Attachments Origin: The inferior orbital margin of the maxilla Insertion: The muscular substance of the upper lip Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The upper lip attachment is more mobile.

Levator Labii Superioris: Action Elevates the upper lip Everts the upper lip If the upper lip were to be pulled toward the maxillary bone attachment, which way would it move? The upper lip would move up toward the maxillary bone, elevating the upper lip. ●

Levator Labii Superioris: Review—Anterior View The levator labii superioris is located between the levator labii superioris alaeque nasi and the zygomaticus minor.

Zygomaticus Minor—Anterior View ● What does the name “zygomaticus minor” tell us? It tells us that this muscle attaches to the zygomatic bone and is smaller than the zygomaticus major muscle.

Zygomaticus Minor (cont’d.)—Anterior View Expression created by the zygomaticus minor

Zygomaticus Minor: Attachments Origin: The zygomatic bone near the zygomaticomaxillary suture Insertion: The muscular substance of the upper lip Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The upper lip attachment is more mobile.

Zygomaticus Minor: Action Elevates the upper lip Everts the upper lip If the upper lip were to be pulled toward the zygomatic bone attachment, which way would it move? The upper lip would move up toward the zygomatic bone, elevating the upper lip.

Zygomaticus Minor: Review—Anterior View The zygomaticus minor is located between the levator labii superioris and the zygomaticus major.

Zygomaticus Major—Anterior View ● What does the name “zygomaticus major” tell us? It tells us that this muscle attaches to the zygomatic bone and is larger than the zygomaticus minor muscle.

Zygomaticus Major (cont’d.)—Anterior View Expression created by the zygomaticus major

Zygomaticus Major: Attachments Origin: The zygomatic bone near the zygomaticotemporal suture Insertion: The modiolus, just lateral to the angle of the mouth Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The angle of the mouth attachment is more mobile.

Zygomaticus Major: Action Elevates the angle of the mouth Draws laterally the angle of the mouth If the angle of the mouth were to be pulled toward the zygomatic bone attachment, which way would it move? The angle of the mouth would move up toward the zygomatic bone, elevating the angle of the mouth.

Zygomaticus Major: Review—Anterior View The zygomaticus major is located between the zygomaticus minor and the buccinator.

Levator Anguli Oris— Anterior View ● What does the name “levator anguli oris” tell us? It tells us that this muscle elevates the angle of the mouth.

Levator Anguli Oris (cont’d.)—Anterior View Expression created by the levator anguli oris. Bilateral contraction of this muscle creates the typical “Dracula” expression in which the canine teeth are exposed.

Levator Anguli Oris: Attachments Origin: The canine fossa of the maxilla (just inferior to the infraorbital foramen) Insertion: The modiolus, just lateral to the angle of the mouth Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The angle of the mouth attachment is more mobile.

Levator Anguli Oris: Action Elevates the angle of the mouth If the angle of the mouth were to be pulled toward the maxillary bone attachment, which way would it move? The angle of the mouth would move up toward the maxillary bone, elevating the angle of the mouth.

Levator Anguli Oris: Review—Anterior View The levator anguli oris is located between the two zygomaticus muscles. Where they overlap, it is located deep to the zygomaticus minor.

Risorius—Anterior View ● What does the name “risorius” tell us? It tells us that this muscle is involved with laughing.

Risorius (cont’d.)— Anterior View Expression created by the risorius

Risorius: Attachments Origin: Fascia and skin superficial to the masseter Insertion: The modiolus, just lateral to the angle of the mouth Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The angle of the mouth attachment is more mobile.

Risorius: Action Draws laterally the angle of the mouth If the angle of the mouth were to be pulled toward the other attachment, which way would it move? It would move laterally.

Risorius: Review—Anterior View The risorius is located directly lateral to the mouth.

Depressor Anguli Oris— Anterior View ● What does the name “depressor anguli oris” tell us? It tells us that this muscle depresses the angle of the mouth.

Depressor Anguli Oris (cont’d.)—Anterior View Expression created by the depressor anguli oris

Depressor Anguli Oris: Attachments Origin: The oblique line of the mandible, inferior to the mental foramen Insertion: The modiolus, just lateral to the angle of the mouth Nerve: The Mandibular branch of the Facial Nerve ● Which attachment is more mobile? The attachment at the angle of the mouth is more mobile.

Depressor Anguli Oris: Action Depresses the angle of the mouth Draws laterally the angle of the mouth If the angle of the mouth were to be pulled toward the mandibular attachment, which way would it move? The angle of the mouth would move down toward the mandible, depressing the angle of the mouth.

Depressor Anguli Oris: Review—Anterior View The depressor anguli oris is located between the risorius and the depressor labii inferioris. Where they overlap, it is superficial to the depressor labii inferioris.

Depressor Labii Inferioris— Anterior View ● What does the name “depressor labii inferioris” tell us? It tells us that this muscle depresses the lower lip.

Depressor Labii Inferioris (cont’d.)—Anterior View Expression created by the depressor labii inferioris

Depressor Labii Inferioris: Attachments Origin: The oblique line of the mandible, between the symphysis menti and the mental foramen Insertion: The midline of the lower lip Nerve: The Mandibular Branch of the Facial Nerve ● Which attachment is more mobile? The lower lip attachment is more mobile.

Depressor Labii Inferioris: Action Depresses the lower lip Draws laterally the lower lip Everts the lower lip If the lower lip were to be pulled toward the mandibular attachment, which way would it move? The lower lip would move down toward the mandible, depressing the lower lip.

Depressor Labii Inferioris: Review—Anterior View The depressor labii inferioris is located inferior to the lower lip. Where they overlap, it is deep to the depressor anguli oris.

Mentalis—Right Lateral View ● What does the name “mentalis” tell us? It tells us that this muscle is involved with the chin.

Mentalis (cont’d.)—Anterior View Expression created by the mentalis

Mentalis: Attachments Origin: The incisive fossa of the mandible Insertion: Fascia and skin of the chin Nerve: The Mandibular Branch of the Facial nerve ● Which attachment is more mobile? The skin of the chin attachment is more mobile.

Mentalis: Actions Elevates the lower lip Everts and protracts the lower lip Wrinkles the skin of the chin If the skin of the chin were to be pulled toward the mandibular attachment, which way would it move? The skin of the chin would move superiorly toward the mandible, elevating the lower lip. If the mentalis were to continue to contract, what would happen? The margin of the lower lip and then the entire lower lip would be forced away from the mouth, everting and protracting the lower lip.

Mentalis: Review—Anterior View The mentalis is located very close to the midline, inferior to the lower lip.

Buccinator—Right Lateral View ● What does the name “buccinator” tell us? It tells us that this muscle is located in the cheek.

Buccinator (cont’d.)— Anterior View Expression created by the buccinator

Buccinator: Attachments Origin: The external surfaces of the alveolar processes of the maxilla and the mandible (opposite the molars) and the pterygomandibular raphe Insertion: Deeper into the musculature of the lips and the modiolus, just lateral to the angle of the mouth Nerve: The Buccal Branches of the Facial Nerve ● Which attachment is more mobile? The attachment into the lips is more mobile.

Buccinator: Action Compresses the cheek against the teeth If the lips were to be pulled toward the mandibular and maxillary attachments, which way would they move? The lips would move posteriorly, compressing the cheeks against the teeth. The buccinator is the muscle used when blowing air out when playing a brass or woodwind instrument and when blowing up a balloon.

Buccinator: Review— Anterior View The buccinator is located deep to the risorius.

Orbicularis Oris—Anterior View ● What does the name “orbicularis oris” tell us? It tells us that this muscle encircles the mouth. ● Compare this muscle to the orbicularis oculi. What do the two muscles have in common? The orbicularis oris is not actually a sphincter muscle, as the orbicularis oculi is, but both muscles encircle the part of the face that they affect. The orbicularis oris encircles the mouth, and the orbicularis oculi encircles the eye.

Orbicularis Oris (cont’d.)— Anterior View Expression created by the orbicularis oris

Orbicularis Oris: Attachments Orbicularis oris is a muscle that, in its entirety, surrounds the mouth. There are 4 parts: Two on the left (upper and lower) and two on the right (upper and lower). Therefore, there is 1 part in each of the 4 quadrants. Each of the 4 parts anchors to the modiolus on that side. From there the fibers traverse through the tissue of the upper or the lower lips. At the midline, the fibers on each side interlace with each other, thereby attaching into each other. ● The orbicularis oris is actually made up of separate linear parts that, together, surround the mouth. It is not a sphincter muscle, but it works in a similar fashion.

Orbicularis Oris Actions Closes the mouth Protracts the lips If the orbicularis oris were to concentrically contract and shorten, what would happen to the overall length of the muscle fibers? They would decrease in length. If the shorter muscle fibers were to create a circle, would they create a larger or a smaller circle? They would create a smaller circle. What would happen to the mouth if the orbicularis oris concentrically contracted and shortened? The mouth would close if it were open, and, as the muscle continued to contract, the lips would protract.

Orbicularis Oris: Review— Anterior View The orbicularis oris surrounds the mouth and is superficial.

Platysma—Anterior View ● What does the name “platysma” tell us? It tells us that this muscle is broad and flat. ● This muscle is also considered to be a muscle of facial expression.

Platysma (cont’d.)— Anterior View Expression created by the platysma

Platysma: Attachments Origin: Subcutaneous fascia of the superior chest The pectoral and deltoid fascia Insertion: Mandible and the subcutaneous fascia of the lower face Nerve: The Cervical Branch of the Facial Nerve ●

Platysma Action Draws up the skin of the superior chest and neck, creating ridges of skin of the neck Depresses and draws laterally the lower lip Depresses the mandible at the TMJ’s When the mandible is held fixed and the platysma is contracted, it causes ridges or wrinkles to form in the neck. What is this action called? It is called drawing up the skin of the superior chest and the neck, creating ridges (or wrinkles) in the skin of the neck.

Platysma: Review—Anterior View The platysma is superficial in the chest and the neck, but in the face, it is deep to the depressor anguli oris, the depressor labii inferioris, and the risorius.