• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/81

Click to flip

81 Cards in this Set

  • Front
  • Back
What are the three main axises of the jaw?
Horizontal, Vertical, Sagittal
The horizontal axis moves in the ___ plane.
Sagittal
The sagittal axis is through (1/both) condyle(s)
1
The vertical axis is through (1/both) condyle(s)
1
The horizontal axis is through (1/both) condyle(s)
both
Which axis is also called the "terminal hinge axis"?
horizontal
The vertical axis moves in the ___ plane.
horizontal
The sagittal axis moves in the ___ plane.
frontal
Average patient is __ mm from each vertical axis to midsagittal plane
55mm
Variations in the horizontal axis can alter cusp position in (closure/working and nonworking) movements.
closure
Variations in the vertical axis can alter cusp position in (closure/working and nonworking) movements.
working and nonworking
A patient typically measures 55mm from the midsagittal plane to the ___ plane
vertical
What is the terms for when the condyles are in the most superior anterior position of the glenoid fossa with the disc interposed?
Centric relation
Centric relation is a term for when the condyles are in the most superior and (anterior/posterior) position of the glenoid fossa with the disc (relaxed/interposed)
anterior, interposed
What two things determine centric relation?
1. muscles
2. articular surface of TMJ
True or False, centric relation is a relative area
False, it is an EXACT position
True or False, centric relation is the most orthopedically stable position
True
True or False, centric relation is stable for the joint, but NOT for the muscles
False, it is the MOST STABLE for the muscles as well
True or False, centric relation is the most repeatable position
True
True or False, centric relation can easily be altered in a short amount of time
False, it is UNchangable in the short term
Centric relation is the limit of the mandibular movement (anteriorly/posteriorly)
posteriorly
The horizontal rotation axis typically measures __mm
20-25mm
What is centric occlusion?
the closure in CR to first tooth contact
What is defined as the deflection of the mandible anteriorly or laterally from the first tooth contact to centric occlusion
centric slide
What is the term for the maximum interdigitation of the teeth?
intercuspal position
True or False, intercuspal position is determined by our habits or tendencies
True
Centric occlusion = centric relation in __% of the population
10%! This means in 90% of the population, CR is not maintained when we fully close our mouths
True or False, intercuspal position can be altered
True
What establishes the most superior position of the mandible?
intercuspal position
When you are in postural position, your jaw is about __ to ___ mm below intercuspal position when the muscles of mastication are at rest
2-4
When your jaw is at rest, 2-4mm below intercuspal position, we call this ___ position
postural (or rest)
What determines postural position?
muscles
True or False, postural position is arbitrary
True
*What are the 7 requirements of optimum occlusion?
1. Both the right and left condyles are in a supero-anterior position in fossae.

2. The articular disc is properly interposed.

3. There is even and simultaneous contact of all teeth.

4. Lighter contacts occur on the anterior teeth than on the posterior.

5. Occlusal forces are directed down long axis of teeth.

6. During laterotrusive movement, the mediotrusive side is discluded immediately.

7. During protrusive movement, all the posterior teeth are discluded immediately.
Protrusion is GUIDED by what 2 things?
1. teeth
2. TMJ
Maximum protrusion is determined by the ___ of the TMJ, NOT the TMJ itself.
ligaments
Which specific ligament limits protrusion?
stylomandibular
What is the normal opening range in mm?
40-60mm
If I told you a patient's condyles are fully rotated with maximum anterior translation, you could assume they were doing what?
opening their mouth as wide as they can (aka maximum opening)
True or False, you only need 2 out of the 3 axises to be recreated on the articulator to get an accurate duplication of the cuspal movement
False, need all 3
The horizontal axis describes movement of both condyles (at the same time/separately) through the sagittal plane
at the same time
About how far can the jaw open (in mm) before the outer oblique portion of the temporomandibular causes the condyle to slide forward?
20-25mm
What ligament limits the horizontal axis?
outer oblique portion of temporomandibular ligament
Translation occurs in the (upper/lower) joint space
upper
Rotation occurs in the (upper/lower) joint space
lower
Which two axises (of the 3) describe movement through 1 condyle only?
Vertical and sagittal (these are AXISES, not PLANES... the horizontal axis is movement through 2 condyles in the sagittal PLANE)
Mediotrusive = working OR non-working?
non-working
Lateriotrusive = working OR non-working?
working
True or False, the rotating condyle is on the mediotrusive side
False, either orbiting condyle on mediotrusive, OR rotating condyle on laterotrusive
Which axises are in motion in left or right lateral excursion?
ALL 3!
How far down can sagittal rotation be? (think inside the TMJ)
the bottom of the eminence
Which axises are in motion in a protrusive movement?
NONE of them!
True or false, you can have centric relation if the disc is out of place... all we care about is the condyle
False, disc must be properly interposed
The condyle rests on the (anterior/posterior) slope of the eminence in centric relation
posterior
True or false, the muscle of mastication help determine CR
True
What does CR stand for?
centric relation
True or False, CR is an exact position
True
How can CR change over a LONG period of time?
bone remodeling can slowly alter the position of the condyle due to changing fossa dimensions
True or False, movement beyond CR is normal
False, it is pathologic... aka, a car wreck or a baseball bat to the face. Or a Yugo to the face.
Rotational movement is limited to __-___ mm
20-25
True or False, because our CR is relatively similar, our Posselt's Envelope of Motion is almost exactly the same from person to person
False, varies depending on person but maintains a relatively similar shape
What ligament limits protrusive movement?
stylomandibular
What ligament stops rotation?
outer oblique portion of temporomandibular
The maximum opening of the jaw is determined by ___.
muscles of mastication
The superior limit of the mandible is determined by ___
intercuspal position
What is represented by red 1?
Maximum protrusion
What is represented by red 2?
The pt where you are protruding and your posterior teeth have slid past your anterior teeth and are now completely in front of them
What is represented by red 3?
The pt at which you are protruding and your posterior teeth are about to complete their slide on the anterior teeth and begin sliding down the facial of them
What is represented by red 4?
The end of anterior guidance (in a protrusive movement)
What is represented by red 5?
CR and ICR, this is rare (10%). Most of the time, ICR will be slightly higher and then CR will be a bit lower [Note: also, the beginning of anterior guidance if shifting to red 4)
What is represented by red 6?
When the outer oblique portion of the temporomandibular ligament is tight and changing rotation to translation
What is represented by red 7?
Maximum opening
The black line between red 1 and red 7 represents what type of movement?
When you go from protrusion to max opening, or max opening to protrusion (1 = protrusion, 7 = max opening)
What does blue 1 indicate? (ignore the direction)
Anterior guidance
Which blue line (2 or 3) is rotation?
2
Which blue line (2 or 3) is translation?
3
What is indicated by the orange dot?
Postural position... when your mouth is relaxed open
When CR and ICR are the same (as in red 5), we call this what?
Centric occlusion
What is indicated by the orange dot?
Centric relation (assuming this person is NOT one of the 10% with matching CR and ICR)
What is indicated by 1 and 3?
Maximum side excursion (right and left respectively)
What is indicated by red 2?
ICP (could be CO if person is one of the 10% with matching ICP and CR)