Occlusion Flashcards
Intro to occlusion: Why study occlusion?
Failure of routine restorations
Fractured teeth and restorations
Intro to occlusion: What is ICP?
The position of the mandible when there is maximum intercuspation of the teeth.
Intro to occlusion: What is RCP?
The first tooth contact when the condyles are fully seated in the glenoid fossa
close to RCP then slide into ICP
Intro to occlusion: What is centric relation?
Relation of the mandible to the maxilla when the condyles are seated in the midmost uppermost position in the glenoid fossa - jaw position nothing to do with the teeth
Intro to occlusion: What is the range of movement within centric relation?
25mm - this is hinge movement
Intro to occlusion: What is protrusive excursion?
Starting from ICP the teeth are kept touching each other and the mandible is moved forward slowly
The teeth which are in contact during this movement are said to be in protrusive guidance
Intro to occlusion: What is one of the main factors that determine which teeth are in protrusive guidance?
Incisor classification
Intro to occlusion: Where does protrusive excursion fall in class I incisors?
On the incisors
Intro to occlusion: Where does protrusive excursion fall in class II Div I incisors?
Shallow anterior guidance on the incisors
Initial guidance may be on posteriors
Intro to occlusion: Where does protrusive excursion fall in class II Div II iincisors?
Very steep overbite results in steep guidance on anterior teeth
Intro to occlusion: Where does protrusive excursion fall in class III incisors?
Very little/no/negative overbite results in minimal/no guidance on anterior teeth in protrusion
Posterior teeth will guide in protrusive movements
Intro to occlusion: Where does protrusive guidance fall in an anterior open bite?
No contact between anterior teeth
Posterior teeth will guide in protrusive movements
Intro to occlusion: how do lateral excursions work?
Working side – the side the jaw is moving to
On the working side guidance can be:
Canine guidance
Group Function
Non-working side - the side opposite to which the jaw is moving
Intro to occlusion: Which teeth are in lateral guidance in lateral excursions?
the ones which remain in contact during the jaw moving to either left or right
Intro to occlusion:What is group function?
More than one guiding tooth