Muscles of Facial Expression of the mouth

Orbicularis oris

Origin: anterior nasal spine

Insertion: Skin of lip

Function: Closes and compresses lips

Levator labii superioris

Origin: Lower part of the orbit

Insertion: SKin of the orbicularis oris

Function: Elevates upper lip

Zygomaticus minor

Origin: Zygomatic bone

Insertion: Orbicularis Oris

Function: Pulls upper lip backward, upward, and laterally

Zygomaticus major

Origin: Zygomatic bone

Insertion: Orbicular oris/ angle of mouth

Function: Elevates corners of mouth

Corrugator/Depressor Supercilii

Origin: nasal bridge/ medial part of orbit

Insertion: skin of the eyebrow

Function: Depresses eyebrow

Depressor Labii Inferioris

Origin: Inferior border of mandible

Insertion: Orbicular oris/ middle of lower lip

Function: Pulls lower lip down 

Depressor angle oris

Origin: Inferior border of mandible

Insertion: Orbicularis oris/ corners of mouth

Function: Pulls corner of mouth down

Mentalis

Origin: Alveolar process of the chin on the mandible

Insertion: Skin of chin

Function: pulls skin of chin up

Buccinator

Origin: pterygomandibular raphe

Insertion: Orbicular oris/ corners of mouth

Function: Pulls corners of mouth back and compresses cheeks

Risorius

Origin: Angle of mandible

Insertion: Skin at the corner of mouth

Function: aids in smiling

Levator Anguli Oris

Origin: Canine fossa

Insertion: Skin at the corner of mouth

Function: Lifts angle of mouth