Occlusion - dynamic Flashcards
What is a jaw relationship
Positional relationship which the mandible bears to the maxilla
What are some vertical jaw relationships
Rest postural position Intercuspal position Returned contact position Occlusal vertical dimension Rest vertical dimension Freeway space
What is rest postural position
At rest that the teeth are apart
Maintained by minimal muscle activity and muscle elasticity
Remains in dentate or Edentulous individuals
P in dentures
What is ICP
,animal interdigitations
Depo on dentition
What is retruded contact position
Condyles retruded in glenoid fossa
Teeth contact 1-2mm posterior to ICP
Clinical significance - symmetrical retrusiin, gives a reproducible relationship between maxilla and mandible
What si occlusal vertical dimension
The face height with teeth in ICP
Measured between 2 arbitrary points
Governed by height of teeth
Measured by Willis gauge
What si the rest postural vertical dimesion
Face height with mandible at rest
Measured between 2 arbitrary points
Shouldn’t alter significantly throughout life
What si the freeway space
Space between teeth in rest position
Difference between RVD and OVD
2-5mm
Reproduce border movements of mandible extremes
Max prtirurison
ICP
Rcp
Max open
What are some anatomical guide planes
Incisor guidance
Cuspal inclines
TMJ
What happens in a lateral excursion to the working and non working side
Working side
- side teeth move
- canine guidance or group function
- condyles - rotate vertical axis, lateral body movement, Bennett move
Non working side
- side away teeth move
- teeth do not occlude
- occasional contact may occur cross bite etc
- condyles - move down and forward over eminence and medially Bennett angle
What si the balanced occlusion concept
Tooth contact during excursions at both working and non working sides
Ideal for dentures - maintain stability, control cusp shape and orientation
Cannot exist in normal dentate
What is masticatory efficiency
Experimental rest to define the capacity to reduce size of food participles by chewing
What are other methods of masticatory efficacy
Subjective measures
Measuring maximal biting force
Swallowing threshold test index
What are some factors affecting masticatory performance
Num of teeth in functioning occlusion
Replacement of teeth fixed or removable
Dentures masticatory less as avoidance, increased chewing strokes
