What muscles are elevator muscles and help close the jaw during mastication? - Answers
Masseter
Medial pterygoid
Temporalis
What muscles are depressor muscles and help open the jaw? - Answers Lateral pterygoid
Suprahyoid (digastric)
What are the two components to the masseter muscle? - Answers Superficial and deep
masseter
What is the origin and insertion of the Masseter muscle? - Answers Origin - the outer surface of
the zygoma
Insertion - Lower boarder of the ramus
What is the action of the masseter muscle? - Answers Elevation of mandible and aids in
protrusion
What are the three components of the temporalis muscle? - Answers Anterior, Middle and
Posterior
What is the origin and insertion of the temporalis muscle? - Answers Origin - Temporal fossa
and lateral surface of the skull
Insertion - Coronoid process and anterior ascending ramus
What is the action of the temporalis muscle? - Answers elevates and retrudes the mandible
What is the origin and insertion of the medial pterygoid muscle? - Answers Origin - pterygoid
fossa
Insertion - medial surface of the mandibular angle
What is the action of the medial ptyergoid? - Answers Elevates the mandible, aids in protrusion.
Acts like a sling with the masseter muscle.
If a unilateral contractions happens of the medial pterygoid, what do you get? - Answers Medio-
trusive movement.
One condyle translates while the other rotates.
Balancing side movement
,What are the two components of the lateral ptyergoid? - Answers Superior and Inferior
What is the origin and insertion of the superior lateral ptyergoid? - Answers Origin -
Infratemporal surface of the greater wing of the sphenoid bone
Insertion - Medial portion of the articular disc (30-40%), Neck of the condyle
What is the origin and insertion of the inferior lateral ptyergoid? - Answers Origin - outer surface
of lateral pterygoid plate
Insertion - neck of condyle
What is the function of the lateral ptyergoid? - Answers Protrudes the mandible
Aids in opening or depressing the mandible
If you get a lateral ptyergoid spasm, which side of the mouth would you have an interference? -
Answers •Discludes the dentition on the affected side (posterior)
•Causes premature contact of the anterior teeth on the contralateral side
What is the origin and insertion of the anterior belly of the suprahyoid digastric muscle? -
Answers •Origin
-lingual surface of mandible at the midline
•Insertion
-intermediate tendon on hyoid bone
•Innervated by the 5th cranial nerve
What is the origin and insertion of the posterior belly of the suprahyoid digastric muscle? -
Answers •Origin
-mastoid notch
•Insertion
-intermediate tendon on the hyoid bone
•Innervated by the 7th cranial nerve
What is the action of the suprahyoid digastric muscle? - Answers Action
-depresses the mandible
-accessory opening muscle
,Which biomechanic movement of the condyle is a "hinge" movement? Where does it occur? -
Answers Rotational movement
-occurs between the condyle and the disc
Which biomechanic movement of the condyle is a "gliding" movement? Where does it occur? -
Answers Translational movement
- occurs between the disc and the fossa
If one joint is not translating, The mandible will deviate to the __________ side - Answers affected
A slight translation in the horizontal plane of the "working side" of the condyle is known as
_________ movement. - Answers Bennett Movement
-Bodily shift of the mandible in the direction of the working condyle
- Just stating that when the jaw is moving right, the mandibular body of the left is is moving over
the horizontal plan.
In a left lateral movement, the right condyle moves ________ and the left condyle shifts in a
________ _______ direction - Answers - forward
- lateral posterior
In a left lateral movement, which side is the "working" side? - Answers Left
In a left lateral movement, which side is the "non-working" or "balancing side" - Answers Right
In para-function, you have Iso________ contractions. Which direction are the forces applied? -
Answers METRIC
Horizontal
In functional contractions, you have Iso________ contractions. Which direction are the forces
applied? - Answers TONIC
Vertical
What is : "A stereotyped movement disorder characterized by rhythmic masticatory muscle
activity associated with tooth grinding and occasional tooth clenching" - Answers Sleep Bruxism
The clinical examination for SB diagnosis includes: - Answers -abnormal tooth wear (attrition,
wear facets)
-masticatory muscle hypertrophy
- muscle tenderness
, T/F. Bruxism is common in children. - Answers True.
T/F. It is reported that occlusal adjustment will reduce bruxism to tolerable levels - Answers
True
Less than 40 bruxism events per hour, is classified as (normal, mild, moderate or severe?) -
Answers Normal
40-75 bruxism events per hour, is classified as (normal, mild, moderate or severe?) - Answers
Mild
75-124 bruxism events per hour, is classified as (normal, mild, moderate or severe?) - Answers
Moderate
125+ bruxism events per hour, is classified as (normal, mild, moderate or severe?) - Answers
Severe
In SB patients, SB episodes occur at a frequency of ______ times per hour of sleep - Answers 5.8
Centric occlusion (CO)
•Habitual occlusion
•Habitual Centric
•The most complete interdigitation of the teeth
These are all different ways of saying? - Answers MIP
Centric Relation, also known as musculoskeletal stable position, is determined by? - Answers -
joint anatomy
-muscles physiology
-disc position
What will the Anterior teeth do during Mutually Protected Occlusion? - Answers -Anterior teeth
will disclude the posterior teeth during excursive movements of the mandible
-Anterior teeth will contact lightly during maximum intercuspation
Criteria for Optimal Occlusion, _____ loading of occlusal forces - Answers Axial
Straight up and down
Traumatic occlusion, can cause hemorrhage and congestion in the __________ - Answers PDL
When doing occlusal adjustments for Working contacts, where do you adjust? - Answers •lingual
incline of buccal cups