MUSCLES OF MASTICATION 



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The posterior part of the muscle fibres, arising from the outer 

 two-thirds of the superior curved line of the occipital bone, 

 are inserted into the epicranial aponeurosis; the anterior part 

 arises from the epicranial aponeurosis and blends with muscles 

 round the orbital margins. 



The epicranial aponeurosis is a thick fascial membrafio 

 ^attached posteriorly to the superior curved lines of the occipital 

 bone, laterally to the temporal bone ; anteriorly, it blends with 

 t*he deep fascia. 



Nerve-supply facial. 



2. The Muscles of Expression are a large number of small 

 muscles in the face which generally have bony origins, but are 

 inserted into the fascia or blend with other muscles ; they are 

 in three groups, associated with the eye, the nose, and the 

 mouth. 



Nerve supply facial. 



3. The Muscles of Mastication are those acting on the 

 temporo-mandibular joint, causing movement of the lower jaw ; 

 the muscles which depress the lower jaw are muscles of the 

 neck, not true muscles of mastication. 



