Читать книгу Temporomandibular Disorders - Robin J. M. Gray - Страница 28

There are two portions to this muscle: the superficial and the deep. The superficial masseter is one of the primary elevator muscles of the mandible during jaw closure, but, as some of its fibres are angled anteriorly, it also assists in protrusion of the mandible. The deep portion is one of the main elevators of the mandible but, as some of its fibres run posteriorly, it is active in retrusion of the mandible.