RA Week 4

What causes facial and neck wrinkles?

Continual muscle contraction.

In what direction do facial wrinkles usually run?

Transverse (perpendicular) to the direction of the muscle fibers.

What happens to facial tissues as muscle tone decreases with age?

They sag, changing facial markings and surface form.

In a living person, what direction does gravity pull tissues?

Inferiorly (downward).

In a deceased person lying on their back, what direction does gravity pull tissues?

Posteriorly.

What is another name for the occipitofrontalis muscle?

Epicranius.

What is the function of the occipitofrontalis?

Raises the eyebrows and moves the scalp anteriorly and posteriorly.

What surface marking is created by the occipitofrontalis?

Transverse frontal sulci.

Where does the occipital belly originate?

Posterior base of the cranium.

Where does the occipital belly insert?

Galea aponeurotica.

Where does the frontal belly originate?

Galea aponeurotica.

Where does the frontal belly insert?

Muscle fibers above the eyes.

What is the strongest chewing muscle?

Temporalis.

What is the shape of the temporalis?

Broad, fan-shaped.

What is the function of the temporalis?

Raises and lowers the mandible.

What is the origin of the temporalis?

Temporal bone.

What is the insertion of the temporalis?

Coronoid process of the mandible.

What is the function of the masseter?

Closes the mandible and adds bulk to the cheek.

Where is the masseter located?

Along the side of the face below the zygomatic arch.

What is the origin of the masseter?

Anterior 2/3 of the zygomatic arch and lower border of the cheekbone.

What is the insertion of the masseter?

Angle of the jaw and lower half of the ramus.

What type of muscle is the orbicularis oculi?

A simple sphincter muscle.

What is the function of the orbicularis oculi?

Closes the eyelids.

What surface marking is created by the orbicularis oculi?

Crow's feet (optic facial sulci).

What is the corrugator also called?

The frowning muscle.

What is the function of the corrugator?

Draws the eyebrows downward and medially.

What surface marking is created by the corrugator?

Vertical interciliary sulci.

What is the function of the levator palpebrae superioris?

Raises the upper eyelid.

What surface marking is created by the levator palpebrae superioris?

Palpebral fold.

Is the procerus paired or unpaired?

Unpaired.

What is the function of the procerus?

Pulls the skin of the nose and lower forehead downward.

What surface marking is created by the procerus?

Transverse interciliary sulci.

What is the function of the orbicularis oris?

Closes the mouth.

Is the orbicularis oris a simple sphincter?

No.

What surface marking is created by the orbicularis oris?

Philtrum.

What is the zygomaticus major also called?

Laughing muscle.

What is the function of the zygomaticus major?

Raises the corners of the mouth.

What surface markings are created by the zygomaticus major?

Angulus oris eminence and helps create the nasolabial fold.

What is another name for the buccinator?

Trumpeter's muscle.

What is the function of the buccinator?

Retracts the corners of the mouth.

What surface markings are created by the buccinator?

Bucco-facial sulcus, angulus oris eminence, lateral cheek wall.

What is another name for the depressor anguli oris?

Triangularis.

What is the function of the depressor anguli oris?

Depresses the corners of the mouth.

What surface marking is created by the depressor anguli oris?

Angulus oris eminence.

What is the overall function of the quadratus labii superioris group?

Raises the upper lip.

Which three muscles make up the quadratus labii superioris group?

Levator labii superioris alaeque nasi, Levator labii superioris, Zygomaticus minor.

What surface marking is created by the quadratus labii superioris?

Nasolabial sulcus.

What is the function of the levator anguli oris?

Elevates the corner of the mouth.

What surface markings are created by the levator anguli oris?

Nasolabial fold and angulus oris eminence.

What is another name for the risorius muscle?

False smile muscle.

What is the function of the risorius?

Pulls the corner of the mouth laterally.

What surface marking does the risorius help create?

Helps form the lateral cheek wall.

What is another name for the depressor labii inferioris?

Quadratus.

What is the function of the depressor labii inferioris?

Depresses the lower lip.

What is the function of the mentalis muscle?

Elevates and protrudes the lower lip and wrinkles the chin.

What surface markings are created by the mentalis?

Mental eminence and may create a cleft chin.

Is the mentalis paired or unpaired?

Unpaired.

What is the function of the platysma?

Depresses the mandible and lower lip; wrinkles the neck and chest.

What surface markings are created by the platysma?

Bucco-facial sulcus, Mandibular sulcus (serrated jawline), Platysmal sulci.

What is the function of the SCM?

Rotates and depresses the head.

Why is the SCM important in restorative art?

It determines the widest part of the neck.

What is the origin of the SCM?

Sternum and clavicle.

What is the insertion of the SCM?

Mastoid process of the temporal bone.

What is the function of the digastric muscle?

Elevates the hyoid bone and helps manipulate the tongue for speech.

What surface marking is created by the digastric muscle?

Cords of the neck.

What is the insertion of the digastric muscle?

Hyoid bone.

What makes the hyoid bone unique?

It is the only bone in the human body that does not articulate with another bone.

What muscle is known as the laughing muscle?

Zygomaticus major.

What muscle is known as the false smile muscle?

Risorius.

What muscle is known as the frowning muscle?

Corrugator.

What muscle is known as the trumpeter's muscle?

Buccinator.

What muscle is the strongest chewing muscle?

Temporalis.

What muscle closes the eyelids?

Orbicularis oculi.

What muscle closes the mouth?

Orbicularis oris.

What muscle raises the upper eyelid?

Levator palpebrae superioris.

What muscle wrinkles the chin?

Mentalis.

What muscle wrinkles the neck?

Platysma.

What muscle rotates the head?

Sternocleidomastoid (SCM).

What muscle forms Crow's Feet (optic facial sulci)?

Orbicularis oculi.

What muscle forms vertical frown lines (vertical interciliary sulci)?

Corrugator.

What muscle forms transverse forehead wrinkles (transverse frontal sulci)?

Occipitofrontalis.

What muscle is associated with the philtrum?

Orbicularis oris.

What muscle is associated with creating the mental eminence?

Mentalis.