Role Of Muscles In Complete Denture

INTRODUCTION Musculature is involved directly in several important phases of complete denture treatment. Most obvious is the action of muscles as prime movers of the mandible hence as the power for repeated occlusion of teeth .They exert a direct influence upon the peripheral extensions , shape and thickness of denture bases , position of teeth both horizontally and vertically and facial appearances.In addition they are active during mastication, speech and deglutition. Following group of muscles are studied in relation to complete dentures Muscles of mastication Muscles of facial expression Muscles of suprahyoid and infrahyoid region Muscles of soft palate Muscles of pharynx Muscles of tongue
Muscles of Mastication Introduction : The muscles of mastication originate from the skull , span the temporomandibular joint and, insert into the mandible. On contraction they tend to move the mandible during movements of mastication. [pic]

Summary of function of muscles of Mastication Elevation (closing) : i. Both side temporalis ii. Both side masseter iii. Both side medial pterygoid Depression (opening) : i. Both side inferior lateral pterygoids ii. Both side suprahyoid muscles iii. Both side infrahyoid muscles Protrusion :- i. Both side lateral pterygoid ii. Both side medial pterygoid iii. Both side superficial heads of masseter Retrusion :- i. Posterior fibers of both side temporalis ii. Deep heads of both side masseter muscles. Right lateral excursion:- i. Right masseter ii. Right temporalis iii. Left lateral pterygoid Left lateral excursion:- i. Left masseter ii. Left temporalis iii. Right lateral pterygoid Muscles of Mastication as in complete dentures Masseter notch: The masseter muscle affects the border of the mandibular