Anatomy of head and neck

muscles of mastication

 

 

MUSCLES OF MASTICATION

 

1)Overview and Topographic Anatomy

GENERAL INFORMATION

Mastication is the process of chewing food in preparation for deglutition (swallowing)

and digestion

All muscles of mastication originate on the skull and insert on the mandible

All muscles of mastication are innervated by the mandibular division of the trigeminal

nerve

All muscles of mastication are derivatives of the 1st pharyngeal arch

Movements of the mandible are classified as:

Elevation

Depression

Protrusion

Retrusion

Side-to-side (lateral) excursion

 

muscle of mastication 

OVERVIEW

muscle of mastication muscle of mastication muscle of mastication 

 

 

2)Arterial Supply :

 

muscle of mastication muscle of mastication 

3)Venous Supply :

 

muscle of mastication

 

 

4)Nerve Supply :

muscle of mastication muscle of mastication 

5)Clinical Corelate :

MASTICATION

Mastication prepares food by chewing for deglutition and digestion

It is the first step in the breakdown of food by:

Making smaller pieces from larger pieces (thus increasing the surface area for digestive

breakdown)

Helping soften and lubricate the food with saliva

BONES INVOLVED

Base of the skull and the mandible

They articulate at the temporomandibular joint (between the squamous portion of the

temporal bone [skull] and the condyle of the mandible)

MUSCLES INVOLVED

4 muscles of mastication:

Masseter

Temporalis

Medial pterygoid

Lateral pterygoid

All muscles of mastication are innervated by the mandibular division of the trigeminal

nerve (nerve of the first pharyngeal arch)

Mastication involves using the muscles of mastication to move the mandible in 1 of 3

planes in an antagonistic fashion:

Elevation/depression

Protrusion/retrusion

Side-to-side excursion

Although the buccinator is not a muscle of mastication, it aids in keeping the bolus of

food against the teeth to help in mastication

 

muscle of mastication