Facial Muscles PDF

# 30^th lecture Theoretical Part: Facial Muscles ## Objectives: at the end of this lecture the student will be able to: 1. Identify muscles of the face and the action of each muscle. 2. Identify muscles of the eye and the action of each muscle. 3. Identify muscles of the mouth and the ac...

# 30^th lecture Theoretical Part: Facial Muscles ## Objectives: at the end of this lecture the student will be able to: 1. Identify muscles of the face and the action of each muscle. 2. Identify muscles of the eye and the action of each muscle. 3. Identify muscles of the mouth and the action of each muscle. 4. Identify muscles of mastication and the action of each muscle. ## Content: 1. Muscles of face. 2. Muscles of eyes. 3. Muscles of mouth. 4. Muscles of mastication ## Muscles of Face. ### 1. Frontalis **Muscle action:** Raise the eyebrows, wrinkling the forehead (Fig. 1). **An example of facial expression:** as in an expression of surprise or fright. *Image of the frontal muscle, with an example of the action and facial expression.* ### 2. Corrugator supercilii: **Muscle action:** Draw the eyebrows together (Fig. 2). **An example of facial expression:** as in frowning. *Image of the Corrugator Supercilii muscle, with an example of the action and facial expression.* ### 3. Procerus: **Muscle action:** Pull the skin of the nose upward, forming transverse wrinkles over the bridge of the nose (Fig. 3). **An example of facial expression:** as in an expression of anger. *Image of the Procerus muscle, with an example of the action and facial expression.* ### 4. Nasalis: (alar portion) **Muscle action:** Widen the apertures of the nostril (Fig. 4) **An example of facial expression:** as in forced or difficult breathing. *Image of the Nasalis (alar portion) muscle, with an example of the action and facial expression.* ### 5. Nasalis: (transverse portion) **Muscle action:** Draw the point of the nose downward, narrowing the nostrils (Fig. 5). *Image of the Nasalis (transverse portion) muscle, with an example of the action and facial expression.* ## Eye Muscles ### 1. Orbicularis oculi: (orbital Part) **Muscle action:** Close the eyelid firmly forming wrinkles that radiate from outer angle (Fig. 6). ### 2. Orbicularis oculi: (Palpebral Part) **Muscle action:** Close the eyelid gently. *Image of the Orbicularis Oculi (orbital Part) muscle, with an example of the action.* ### 3. Levator palpebrae superioris: **Muscle action:** Raise the upper eyelid (Fig. 7). *Image of the Levator palpebrae superioris muscle, with an example of the action.* ### 4. Rectus medialis oculi and rectus lateralis oculi **Muscle action:** Right Rectus Medialis and Left Rectus Lateralis are used to look horizontally toward the left (as illustrated in fig 8). *Images of the Right Rectus Medialis and Left Rectus Lateralis muscles, with an example of the action.* ## Muscles of the mouth ### 1. Risorius: **Muscle action:** Draw the angle of the mouth backward (Fig. 9). *Image of the Risorius muscle, with an example of the action.* ### 2. Zygomaticus Major: **Muscle action:** Draw the angle of the mouth upward and outward (Fig. 10). **An example of facial expression:** as in smiling. *Image of the Zygomaticus Major muscle, with an example of the action and facial expression.* ### 3. Levator Labii Superioris: **Muscle action:** Raise and protrude the upper lib (Fig. 11). **An example of facial expression:** as in show the upper gum *Image of the Levator Labii Superioris muscle, with an example of the action and facial expression.* ### 4. Depressor Labii Inferiors and platysma.: **Muscle action:** draw the lower lib and the angle of the mouth downward and outward tensing the skin over the neck (Fig. 12). *Image of the Depressor Labii Inferior and Platysma muscles, with an example of the action.* ### 5. Mentalis: **Muscle action:** raise the skin of the chin and Protrude the lower lib (Fig. 13). **An example of facial expression:** as in pouting. *Image of the Mentalis muscle, with an example of the action and facial expression.* ### 6. Orbicularis Oris: **Muscle action:** close and protrude lips (Fig. 14). **An example of facial expression:** as in whistling *Image of the Orbicularis Oris muscle, with an example of the action and facial expression.* ### 7. Depressor anguli Oris: **Muscle action:** draw down the angle of the mouth (Fig. 15). *Image of the Depressor anguli Oris muscle, with an example of the action.* ### 8. Buccinator: **Muscle action:** press the cheeks firmly against the side teeth and pull back the angle of the mouth (Fig. 16). **An example of facial expression:** as in blowing a trumpet. *Image of the Buccinator muscle, with an example of the action and facial expression.* ## Muscles of mastication ### 1. Pterygoideus lateralis: **Muscle action:** open the mouth slightly, protrude the lower jaw, then move the lower sideways, firstly toward the right then toward the left (Fig. 17). *Image of the Pterygoideus lateralis muscle, with an example of the action.* ### 2. Pterygoideus medialis, temporalis and Masseter: **Muscle action:** close the jaws, clenching the teeth and bite firmly with the mouth slightly open (Fig. 18). *Image of the Pterygoideus medialis, temporalis and Masseter muscles, with an example of the action.*