The articulary system II Flashcards
Muscle of the Mandible
Masseter Temporalis Medial/internal pterygoid Lateral/external pterygoid Digastric Mylohyoid Geniohyoid
Muscles of the Mandible : closers
Jaw closers - Elevation of the mandible Masseter Temporalis Internal pterygoid External pterygoid
Muscles of the Mandible: openers
Jaw openers – Lowering of the mandible
Digastric muscle (anterior belly only)
Mylohyoid muscle
Geniohyoid muscle
The velum
Velum or “the curtain”
Four tissues of layers
Glandular layer toward the under surface (oral surface) with adipose tissue
Muscle tissue in the middle layer
Upper front layer with connective tissue (tendons)
Lower back layer with glandular tissue
The velum : Uvula
Uvula or “the little grape”
Has a richer vascular system than the velum (soft palate
The velum: Palatal levator/levator veli palatini
Palatal levator/levator veli palatini
Forms much of the bulk of the velum
Arises from the cartilagious portion of the eustachian tube
Fibers insert into the side of the velum and spread out beyond the midline
They join the fibers of the palatal levator of the opposite side
Looks like a braided string of muscle fibers
Draws the velum upward and backward
The velum: Palatal tensor/tensor veli palatini
Palatal tensor/tensor veli palatini
Lies on the outer side of the palatal levator
Has a vertical and horizontal component
Vertical component: fibers arise from the cartilaginous portion of the eustachian tube and connects to the sphenoid bone
Horizontal component: fibers insert into the hard plate and velum
Dilates the Eustachian tube
Does not really seem to tense the velum
The velum: Uvulus (Musculus Uvulae)
Uvulus (Musculus Uvulae) The only intrinsic muscles of the velum Extends through the soft palate Only a few fibers reach into the uvula Shortens the velum Lifts the velum Increases the thickness of the velum Controls the stiffness of the velum
The velum: Palatopharyngeus muscle
Palatopharyngeus muscle
Its fibers arise from the lower half of the lateral wall of the pharynx and thyroid cartilage
Pass through the posterior faucial pillar
Insert into the soft palate
It is an antagonistic muscle to the palatal levator muscle
Narrows the pharynx
Pulls the velum down
Pharyngeal Muscles: Salpingopharyngeus
Salpingopharyngeus Superior pharyngeal constrictor Middle constrictor Inferior constrictor ( including cricopharyngeus)
Pharyngeal Muscles: Superior constrictor
Superior constrictor
Decreases the cross-sectional area of the pharynx, especially during swallowing
Assists to close of the passage way to the nasopharynx and prevents food from entering the nasopharynx
Pharyngeal Muscles: Middle constrictor
Middle constrictor
Decreases the cross-sectional area of the pharynx by pulling forward on the posterior pharyngeal wall and inward on the lateral pharyngeal wall
Pharyngeal Muscles: Salpingopharyngeus
Salpingopharyngeus
Elevation of the lateral pharyngeal wall
Pharyngeal Muscles:Inferior constrictor (Thyropharyngeus)
Inferior constrictor (Thyropharyngeus)
Decreases the cross sectional area of the lower pharynx
Inferior constrictor (Cricopharyngeus)
Constricts the upper part of the esophagus
Cricopharyngeus has to relax to open up esophagus
Pharyngeal Muscles: Stylopharyngeus
Stylopharyngeus
Pulls the lateral wall of the pharynx toward the side
Increases the cross-sectional area of the pharynx
