Occlusal Morphology Flashcards
What are the 3 structures controlling movement patterns?
Left TMJ, Right TMJ, and Anterior teeth
If the posterior teeth make \_\_\_\_\_ during lateral or protrusive movement: •We lose the class III lever advantage •We lose the biomechanical advantage of muscle inhibition, and the masseter, temporalis and medial pterygoid muscles can contract •We initiate the class I or the class II levers which can create heavy pressures on posterior teeth.
contact
Condylar Guidance and The two temporomandibular joints are the ____ controlling factors
Posterior
The angle at which the condyle moves away from a horizontal reference plane
Condylar guidance angle•
Is the condylar guidance angle greater or lesser for the rotating and protruding condyle?
Lesser
Is the condylar guidance angle greater or lesser for the orbiting?
Greater
_____ condyle Moves forward, downward, and inward•Moves over the steeper medial wall of the fossa•Larger angle than protrusive
Orbiting Condyle
_____ Condyle Movement•Moves forward and downward, contacting the articular eminence.•Smaller angle than the orbiting condyle
Protrusive condyle movement
Angle made between the protrusive movement of the condyle and the orbiting border movement
Fisher Angle
What are the 2 anterior controlling factors?
Anterior guidance and anterior teeth
Determine how the anterior portion of the mandible moves
Anterior teeth
- Dictated by how the incisal edges of the mandibular teeth glide over the lingual inclines of the maxillary teeth.
- A variable rather than a fixed factor
Anterior Guidance
Altered by: •Restorations •Orthodontics •Extractions •Caries •Habits •Tooth Wear
Anterior guidance
_____ Influenced by pathway the cusp tip travels across it’s opposing tooth•Must harmonize with the opposing tooth
Tooth Morphology
Should there be any cusp tips touching in mandibular excursions?
No
Each cusp tip moves laterally, through a ____ or ______ on the opposing tooth.
groove or embrasure space
T/F: The nearer a specific tooth is to the anterior teeth, The more the anatomy of the anterior teeth will influence it’s movement
True
______ angle dictates anterior teeth disclusion
Anterior angle
_____ angle dictates posterior teeth disclusion
Condylar
Should cusp tips with flatter posterior and anterior controlling factors be flatter or steeper?
Flatter
Should cusp tips with steeper posterior and anterior controlling factors be flatter or steeper?
Steeper
Do you want sharp or flat cusps?
Sharp
What are the 2 factors influencing the vertical determinants?
Height of cusps and depths of fossa
The _____ the eminence•The more the condyles must move inferiorly•Thus greater vertical movement•Thus allows for steeper posterior cusps
steeper
The steeper the angle of the eminence the _____ the posterior cusp tips may be
steeper
As horizontal overlap increases the anterior guidance angle _____
decreases
As vertical overlap increases the anterior guidance angle _____
increases
______ in Horizontal Overlap leads to Decreased anterior guidance angle•Less vertical component•Flatter posterior cusps are required.
Increase
An imaginary surface that touches the incisal edges of the incisors and cusp tips of the occluding surfaces of the posterior teeth.
Plane of Occlusion
If there is a greater angle of the plane of occlusion, you can have flat or steep cusps?
Steeper cusps
AS THE PLANE OF OCCLUSION BECOMES MORE PARALLEL TO THE ANGLE OF THE EMINENCE, THE POSTERIOR CUSPS MUST BE MADE _______
SHORTER
THE FLATTER THE PLANE OF OCCLUSION, THE ______ THE CUSP HEIGHT CAN BE
GREATER
If the Curve of Spee has a SHORT RADIUS: the ANGLE at which the mandibular teeth move away from the maxillary teeth WILL BE ____ THAN WITH A LONG RADIUS, therefore the CUSPS will need to be SHORTER
LESS
If the Curve of Spee has a SHORT RADIUS: the ANGLE at which the mandibular teeth move away from the maxillary teeth WILL BE Less THAN WITH A LONG RADIUS, therefore the CUSPS will need to be ______
SHORTER
Curve of Spee, a longer radius causes a _______ plane of occlusion.
flatter plane
A shorter radius cause a more ______ plane of occlusion.
acute
As the mandible moves forward, the posterior part of the plane will also move forward and will contact the maxillary arch. The _____ the arc (curve of Spee), the more probable is the chance of contact.
greater
As the mandible moves forward, the posterior part of the plane will also move forward and will contact the maxillary arch. Thus with a ____ arch, the cusps can be slightly longer.
flat
The mandible is moving away from a horizontal reference plane at a 45 degree angle. The flatter the plane of occlusion, the greater will be the angle at which the mandibular posterior teeth move away from the maxillary posterior teeth and therefore the _____ the cusp can be.
taller
If the plane of occlusion is rotated more posteriorly, it can be seen that more posterior teeth will be positioned distal to the perpendicular from the reference plane, and will have to have _____ teeth to prevent contact which can be classified as interferences.
shorter
Posterior teeth located _____ to the radius need shorter cusps than those located _____ to the radius.
distal; mesial
An angle formed between the path of the orbiting condyle and the protrusive movement path of the condyle as measured on the horizontal plane.
Bennett Angle
What 3 movements does the orbiting condyle make?
Downward
Forward
Inward
The tight ____ ligament on the rotating condyle will prevent lateral movement of this condyle
Capsular ligament
_____ ligament: VERY TIGHT•PURE ARCING MOVEMENT AROUND THE ROTATING CONDYLE•NO LATERAL TRANSLATION OF THE MANDIBLE
Temporomandibular ligament
THE MORE MEDIAL THE MEDIAL WALL IS FROM THE CONDYLE ,THE _____ LATERAL TRANSLATION MOVEMENT
MORE
The greater the lateral translation movement the _____ the posterior cusp tips must be.
shorter
Latero-superior movement requires a _____ posterior cusp
shorter
Inferior movement allows _____ cusps
taller
The rotating condyle movements occur within a ___ degree cone
60 degree cone
The more superior the lateral translation movement of the rotating condyle (1), the _____ is the posterior cusp.
shorter
The more inferior the lateral translation movement (3) the ______ is the cusp.
taller
If the space btwn condyle and fossa is denser and does not allow the immediate movement, the result is (2), which displays a more gradual ______
progressive side shift
If you have immediate movement due to larger distance between condyle and medial wall of fossa on lateraltrusive movement, you will have the movement called ______
immediate side shift
The greater the distance of the tooth from the rotating condyle the _____ the angle formed by the laterotrusive and mediotrusive pathways.
wider
Teeth in the anterior, e.g., premolars will have _____ angles between working and balancing pathways
larger
Teeth in posterior e.g., molars, will have _____ angles between working and balancing pathways
smaller
Greatest angle between working and balancing pathways are by teeth ______ from both rotating condyle and midsagittal plane
furthest away
Smallest anges between working and balancing pathways are generated by teeth _____ both the rotating condyle and midsagittal plane
nearer
As the amount of lateral translation movement increases, the angle between the mediotrusive and laterotrusive pathways generated by the centric cusp tips ______
increases
The greater the intercondylar distances, the ______ the angle formed by the laterotrusive and mediotrusive pathways.
smaller
As intercondylar distance increases the distance between the condyle and the tooth ______
increases
Greater vertical overlap leads to ____ cusps
Taller
Greater horizontal overlap leads to ______ cusps
Shorter
More parallel to the condylar guidance leads to _____ cusps
Shorter
More acute the curve of spee requires ______ cusps
Shorter
Greater the lateral translation movement requires _____ cusps
Shorter
More superior movement of the rotating condyle in lateral translation movement requires _____ cusps
Shorter
Greater immediate side shift in lateral translation movement requires _____ cusps
Shorter
Greater the distance from rotating condyle leads to ____ the angle is between laterotrusive and mediotrusive pathways
Wider
Greater the distance from midsagittal plane, the _____ the angle is between laterotrusive and mediotrusive pathways
Wider
Greater the lateral translation movement, the ____ the angle between laterotrusive and mediotrusive pathways
Wider
Greater the intercondylar distance, the _____ the angle between laterotrusive and mediotrusive pathways
Smaller