1. Platysma
Origin: Fascia over deltoid and pectoralis major muscles
Insertion: Mandible
Action: Draws outer part of lower lip inferiorly and posteriorly, and draws mandible
2. Depressor labii inferioris
Origin: Mandible
Insertion: Skin of lower lip
Action: Depresses lower lip
3. Orbicularis oris
Origin: Muscle fibers surrounding opening of mouth
Insertion: Skin at corner of mouth
Action: Closes and protrudes lips, and compresses lips against teeth
4. Corrugator supercilii
Origin: Medial end of superciliary arch of frontal bone
Insertion: Skin of eyebrow
Action: Draws eyebrows inferiorly, and wrinkles skin of forehead vertically
5. Orbicularis oculi
Origin: Medial wall of orbit
Insertion: Circular path around orbit
Action: Closes eye
6. Occipitofrontalis
Origin: Epicranial aponeurosis
Insertion: Skin superior to supraorbital margin
Action: Draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead horizontally