The Skull and Jaw Flashcards
What are the 6 bones that make up the skull?
Frontal, Occipital, Sphenoid, Ethmoid, Temporal and Parietal bones.
What do you call the line of union in an immoveable articulation?
A suture
Which bone is the largest and strongest of all the facial bones?
The Mandible
The Coronal Suture is located between which 2 bones of the skull?
Between the frontal and the parietal bones.
The Sagittal Suture is located between which 2 bones of the skull?
The 2 parietal bones.
What is the Bregma?
The meeting point between the coronal and sagittal sutures.
The Squamous suture is located between which 2 bones of the skull?
Between the parietal and temporal bones.
The Lambdoid suture is located between which 3 bones of the skull?
The occipital, temporal, and parietal bones.
What is the Lambda?
The meeting point of the lambdoid and the sagittal sutures.
What is the pterion?
Connection between the sphenoid, temporal, frontal and parietal bones.
What suture is between the frontal and parietal bones?
Coronal suture
What suture is between the right and left parietal bones?
Sagittal Suture
What is the name of the meeting point between the coronal and sagittal sutures?
The Bregma
What suture is between the parietal and temporal bones?
Squamous Suture
What suture is between the occipital , temporal and parietal bones?
Lambdoid Suture
What is the meeting point of the lambdoid and sagittal sutures?
Lambda
What is the connection between the sphenoid, temporal, frontal and parietal bone?
Pterion
What is the weakest part of the skull?
Pterion
Name the 4 different kinds of sinus in the skull and where they are located.
Frontal - 2 above each eye near midline
Sphenoidal - 2 post portion of nasal cavity
Ethmoidal - 2 either side of upper portion of nasal cavity
Maxillary - 2 lateral to nasal cavity extending from floor of orbital socket to the upper maxillary teeth.
The Temporomandibular joint is what type of joint?
Synovial Modified hinge joint.
What are the available movements from the Temporomandibular joint?
Depression: opening the mouth
Elevation: closing the mouth
Protaction:anterior translation of the mandible
Retraction: posterior translation of the mandible
Deviation : movement from side to side
The Temporalis muscle attaches from where to where?
Temporal Bone (fossa) - Coronoid process and anterior ramus of the mandible.
What are the actions avaliable to the Temporalis muscle?
Elevation of mandible
Retraction of mandible (more the horizontal/ posterior fibres)
The Masseter muscle attaches from where to where?
inferior border of zygomatic arch - angle of the mandible
What actions are avaliable to the masseter muscle?
Elevation of the mandible
Protraction of the mandible
(Deep fibres) Retraction of the mandible (from a protracted position)
The Lateral Pterygoid attaches from where to where? (split your answer into superior and inferior head)
Superior head :Greater wing of sphenoid - articular disc
Inferior head: Lateral surface of the lateral pterygoid plate - neck of the mandible
What actions are avaliable to the Lateral Pterygoid muscle?
Protraction of the mandible
Translation (ant/post) control of the articular disc ( superior head )
Depression of mandible (once translation occurs)
Contralateral deviation of the mandible
The Medial Pterygoid attaches from where to where?
Medial surface of the lateral pterygoid plate - pterygoid tuberosity (inner surface of the angle of mandible)
What actions are avaliable to the Medial Pterygoid?
Elevation of mandible
Protaction of the mandible
Contralateral deviation of the mandible
The Hyoids as a group are responsible for what action of the mandible?
Assist in depression of the mandible
Action Summary : Depression of the mandible is caused by which muscles of mastication?
Hyoids
Lateral Pterygoid
Action Summary: Elevation of the mandible is caused by which muscles of mastication?
Temporalis
Masseter
Medial Pterygoid
Lateral Pterygoid ( superior head controls the return of the disc)
Action Summary: Protraction of the mandible is caused by which muscles of mastication?
(superficial)
Masseter
Lateral Pterygoid
Medial Pterygoid
Action Summary: Retraction of the mandible is caused by which muscles of mastication?
(Deep)
Temporalis
Masseter
Action Summary: Deviation of the mandible is caused by which muscles of mastication?
Contralateral Pterygoids
When you are opening your mouth the motion from beginning to mid range mostly comes from what part of the anatomy?
Primarily rotation of the head of the mandible in the mandibular fossa.
When you are opening your mouth the motion from mid range to end range mostly comes from what part of the anatomy?
Primarily translation of the head of the mandible from the fossa onto the articular tubercle.
During the ROM of the mouth opening after the mid point what happens to the articular disc and why?
The articular disc is pulled anteriorly by the lateral pterygoid to maintain joint surface congruency.
When the mouth closes what pulls the articular disc back into place?
Elastic fibers that are attached to the back of the articular disc pull it back into place and the movement is controlled (eccentrically) by the lateral pterygoid.
