Anatomy Chapter 2 Muscle Actions

Frontoccipitalis action

Horizontally wrinkles skin of forehead, elevates eyebrows

Temporalis action

Elevates mandible

Orbicularis Oculi

Closes eyelids

Orbicularis oris

Compression & protrusion of lips

Corrugator supercilii

Draws eyebrows inferiorly and medially

Nasalis

Draws ala of nose towards nasal septum, compresses nostrils

Procerus

Draws down medial angle of eyebrows

Zygomaticus major

Draws angle of mouth posteriorly and superiorly

Zygomaticus minor

Elevates upper lip

Mentalis

Elevates and protrudes lower lip

Depressor Anguli Oris

Depresses angle of mouth

Depressor labii inferioris

Depresses lower lip and draws it laterally

Risorius

Retracts angle of mouth

Platysma

Tenses skin of neck

Auricularis

Retracts and elevates auricle

Buccinator

Compresses cheeks

Levator nasolabialis

Elevates upper lip and dilates nostrils

Levator labii Superioris

Elevates upper lip and dilates nostrils

Masseter

Elevates and protrudes mandible

Medial pterygoid

Protrudes and elevates mandible, side to side movements

Lateral pterygoid

Protrudes mandible, side to side grinding

Genioglossus

Depress and protrude tongue

Hyoglossal action

Depress and retract tongue

Action of styloglossal

Retract and curl sides of tongue

Actions of palatoglossal

Elevate tongue, depresses palate

Anterior digastric action

Elevate hyoid and lower mandible

Posterior digastric action

Move hyoid posterior

Stylohyoid

Moves hyoid posterior and elevate tongue

Mylohyoid action

Form floor of mouth and elevate hyoid

Geniohyoid action

Protrude hyoid and tongue

Sternohyoid action

Depress hyoid

Sternothyroid action

Depress thyroid

Omohyoid action

Depress hyoid

Thyrohyoid

Longus Colli