Lecture 5 - Muscles of Facial Expression - PDF

COMMONWEALTH OF AUSTRALIA Copyright Regulation WARNING This material has been reproduced and communicated to you by or on behalf of the...

COMMONWEALTH OF AUSTRALIA Copyright Regulation WARNING This material has been reproduced and communicated to you by or on behalf of the University of Sydney in accordance with section 113P of the Copyright Act 1968 (Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Do not remove this notice The University of Sydney Page 1 Lecture 5 Muscles of Facial Expression Dr Filip Vujovic DDS,PhD Slides: Dr Jonathan D. Hakim School of Medical Sciences The University of Sydney Lithograph from Dr Richard Quin’s ”The Anatomy of the The University of Sydney Arteries of the Human Body” (1844) Page 2  Learning Objectives Muscles of the head and neck – Locate and identify muscles of the head and neck. – Identify the muscles responsible for facial expression and mastication. – Identify muscles of the tongue – Identify muscles of the neck – Describe the origin, insertion and action of muscles of the head and neck. The University of Sydney Page 3  Lecture Outline Categories of muscles in the head and neck region Definitions and descriptions of muscles Muscles of facial expression – Scalp/forehead/eyebrows – Eyes – Nose – Mouth The University of Sydney Page 4  Muscles of head and neck - categories Facial expressions (this lecture) – speaking, smiling and expression Mastication (next lecture) – Chewing and swallowing Tongue (oral cavity lecture) – Swallowing Neck (next lecture) – Movement of head and neck, speaking Pharynx The University of Sydney Page 5  Muscles of Facial Expression - Overview – Skeletal muscle (reddish/fleshy) – Belly (contractile), Tendons (non-contractile) – Striated – Voluntary contractions – Attached either directly or indirectly to bones, cartilages, ligaments, fascia, organs, skin or mucous membranes – Muscles of facial expression generally originate from bone and insert into skin where the short tendons intertwine with the collagen of the dermis. All muscles of facial expression are paired except orbicularis oris The University of Sydney Page 6  Scalp, forehead & eyebrows Muscles of Facial Expression - An Overview Nose Eyes Mouth Cheek Chin & The University Superficial Neckof Sydney Page 7 Scalp, Forehead & Eyebrows The University of Sydney Page 8 Scalp, Forehead & Eyebrows Occipitofrontalis – Has two bellies – Frontal belly and Occipital belly joined by epicranial aponeurosis (galea aponeurotica) – Origins & Insertion: – Frontal – aponeurosis to skin of eyebrows – Occipital – superior nuchal line to aponeurosis – Actions – Surprise (frontal/occipital) – Frown (frontal) Frontal belly of occipitofrontalis Epicranial aponeurosis is a tough, fibrous sheet of connective tissue that forms the third layer of the scalp. The University of Sydney Page 9 Scalp, Forehead & Eyebrows Corrugator supercilli Corrugator supercilli – Origin & Insertion: – Supraorbital ridges to skin of eyebrow – Actions – Frown The University of Sydney Page 10 Scalp, Forehead & Eyebrows Procerus – Origin & Insertion: – Nasal bones to skin of eyebrow – Actions – Frown The University of Sydney Page 11  Question Which forehead muscle would be responsible for this expression? The University of Sydney Page 12 Eyes & Nose The University of Sydney Page 14 Eyes Orbicularis oculi – Has two parts – Orbital part (around orbit) – Palpebral part (eyelid) – Origins & Insertion: – Orbital rim to eye lid – Actions – Squinting (orbital) – Gentle closing eyelids (palpebral) The University of Sydney Page 15 Nose Nasalis – Origins & Insertion: – Maxilla to Nasal bone – Actions – Elevates and opens nostrils, wrinkles nasal skin The University of Sydney Page 16 Forehead, Eyes, Nose Frontal belly of occipitofrontalis (10) Orbicularis oculi (18) Procerus (21) Nasalis (17) The University of Sydney Page 17  Question Which muscles are responsible for this expression? The University of Sydney Page 18 Mouth The University of Sydney Page 20 Mouth, Lips, Cheeks, Chin – Circle with radiating spokes – Opening – Orbicularis oris – Cheek – Buccinator – Elevators – Levator labii superioris alaeque nasi – Levator labii superioris – Zygomatic minor – Zygomatic major – Levator anguli oris – Depressors – Risorius – Depressor anguli oris – Depressor labii inferioris – Mentalis – ofPlatysma The University Sydney Page 21 Modiolis – Small fibromuscular structure at the corner of the mouth, * * where fibres from multiple facial muscles converge, and helps coordinate the action of these muscles – Formed by nine muscles* that * converge at the corner * * (angle) of the mouth * * * * * The University of Sydney Page 22 Mouth Orbicularis oris – Origins & Insertion: – Maxilla, mandible & modiolis to skin & mucous membrane of mouth – Actions – Closes mouth, compresses and protrudes lips (kissing) and thinning (pursing) The University of Sydney Page 23 Cheek Buccinator (7) – Origins & Insertion: – Alveolar part of maxilla & mandible to modiolis and orbicularis oris – Actions – Blowing up a balloon, presses cheeks against molar teeth, assists mastication The University of Sydney Page 24 Elevators Levator labii superioris alaeque nasi (5) – Origins & Insertion: Maxilla to alar cartilage – Actions: Flaring nostrils Levator labii superioris – Origins & Insertion: Maxilla to upper lip skin – Actions: Elevate and retract upper lip Zygomatic minor – Origins & Insertion: Zygomer to upper lip skin – Actions: Elevate and retract upper lip Zygomatic major – Origins & Insertion: Zygomer to modiolis – Actions: Elevate and retract upper lip, smiling Levator anguli oris – Origins & Insertion: Maxilla to modiolis – Actions: Elevate and retract upper lip, widens The University of Sydney mouth grinning Page 25 Depressors – Lower facial expression – Depress and retract lip Risorius – Origins & Insertion: Buccal skin to modiolis – Actions: Depresses lips, widens lips Depressor labii inferiois – Origins & Insertion: Platysma and mandible to skin of lower lip – Actions: Depresses & retracts lower lip, pouting, sadness Depressor anguli oris – Origins & Insertion: Mandible to modiolis – Actions: Depresses lips, sadness The University of Sydney Page 26 Depressors Mentalis – Origins & Insertion: Mandible to skin of chin – Actions: Elevates skin of chin, doubt Platysma – Origins & Insertion: subcutaneous tissue near clavicle to mandible/modiolis and skin of chin – Actions: Tenses skin of inferior face, wrinkles neck, depresses lip & mandible, stress The University of Sydney Page 27  Levator labii superioris alaeque nasi (14) Levator labii superioris (13) Zygomaticus minor (29) Levator anguli oris (12) Zygomaticus major (28) Buccinator (5) Orbicularis oris (19) Depressor labii inferioris (7) Depressor anguli oris (6) The University of Sydney Page 28 McMinn, R.M.H., Hutchings, R.T., Pegington, J. and Abrahams, P., 1988. A colour atlas of human anatomy. Year Book Medical Publishers.  2. Corrugator supercilii 15. Procerus 6. Levator labii superioris 8. Levator anguli oris 18. Zygomatic minor 7. Zygomatic major 19. Buccinator 20. Risorius 21. Depressor labii inferioris 13. Mentalis 12. Depressor anguli oris 22. Platysma The University of Sydney Page 29 Photographic Atlas of Anatomy, 9th Ed, 2006, Johannes W. Rohen, Elke Lutjen-Drecoll, Chihiro Yokochi  Questions A. Which muscles are responsible? B. Which muscles are responsible for a wide smile? The University of Sydney Page 30