1.
Muscle: Platysma
Origin: Fascia that envelops not only the clavicle, but also the acromial region and the superior portions of the pectoralis major and deltoid muscles.
Insertion: In the lower border of mandible, skin of buccal/cheek region, lower lip, modiolus, orbicularis oris muscle.
Action: Depresses mandible and angle of mouth. Moreover, it tenses the skin of the lower face and the anterior neck.
2.
Muscle: Mentalis
Origin: Mandible (lower jaw). Composes of the lower lip from the lower to the lower part of the chin.
Insertion: Underneath the skin of chin
Action: Mostly elevates, everts, and protrudes lower lip. Capable of wrinkling the skin of the chin.
3.
Muscle: Orbicularis oris
origin: It is in the medial aspects of maxilla and mandible,
insertion: skin of the lips.
Action: Is capable of closing the mouth. As for the lips, this muscle is able to compress and protrude it.
4.
Muscle: Corrugator supercilii
Origin: In the medial end of superciliary arches.
Insertion: The skin located above the middle of supraorbital margin.
Action: Contracts the eyebrows by lowering (Scowling).
5.
Muscle: Orbicularis oculi
Origin: Frontal bone (in the nasal part)
Insertion: Skin of orbital region. Furthermore, superior and inferior tarsal plates.
Action: Capable of doing three actions.
Orbital part: Closes eyelids tightly
Palpebral part: Closes eyelids gently
Deep palpebral part: Compresses lacrimal sac
6.
Muscle: Occipitofrontalis (frontal belly)
Origin: skin of eyebrow and muscles of forehead Occipital belly (occipitalis)
Insertion: Epicranial aponeurosis
Action:
Frontal belly: Elevates eyebrows, wrinkles skin of forehead
Occipital belly: Retracts scalp
Source: Muscles of facial expression. (2020). Kenhub. https://www.kenhub.com/en/library/anatomy/orbicularis-oris-muscle