Dynamic Occlusion Flashcards
define occlusion
the contact relationship of teeth or equivalent
define articulation
the dynamic relationship of teeth when in sliding contact (chewing -> movement)
define jaw relationship
positional relationship which the mandible bears with to the maxilla
rest/postural position
where are the teeth in the rest position?
apart
what is the clinical significance of the rest position?
it is reproducible (the same throughout life) so good landmark e.g. full dentures
how is the intercuspal position categorised?
angles classification
incisor relationship
what is the angles classification?
relationship between the MB cusp of U6 and MB groove of L6
what is a class I angles classification?
mesiobuccal cusp of U6 in line with mesiobuccal groove of L6
what angles classification is this?
class I
what is a class II angles classification?
mesiobuccal cusp of U6 anterior to mesiobuccal groove of L6
what angles classification is this?
class II
what is a class III angles classification?
mesiobuccal cusp of U6 posterior to mesiobuccal groove of L6
what angles classification is this?
class III
what is incisor relationship?
relates lower incisor tip to cingulum plateau of the upper incisor
what is a class I incisor relationship?
lower incisal edge contacts with upper cingulum plateau
what incisor relationship is this?
class I
what is a class II div I incisor relationship?
lower incisal edge posterior to upper cingulum plateau
and overjet
what incisor relationship is this?
class II div I
what is a class II div II incisor relationship?
lower incisal edge posterior to upper cingulum plateau
and overbite
what incisor relationship is this?
class II div II
what is a class III incisor relationship?
lower incisal edge anterior to upper cingulum plateau (underbite)
what incisor relationship is this?
class III
what is an overbite?
overlap in vertical plane
what is an open bite?
no overbite or tooth contact
what is an overjet?
overlap in horizontal plane
what is the retruded contact position (RCP or ligamentous position)?
Condyles retruded into glenoid fossa
Do it by getting the patient to curl their tongue back
what is the clinical significance of the retruded contact position RCP?
Symmetrical retrusion so gives a reproducible relationship between the maxilla and mandible
Good if patient cant close jaw reproducibly e.g. missing teeth, wondering jaw
what is the Occlusal vertical dimension (OVD)
The face height between 2 reference points when the teeth are in ICP (chin and nose)
Measured using Willis gauge
what is the rest/postural vertical dimension (RVD)?
The face height between 2 reference points when the teeth are in RP
what is the freeway space?
The space between the teeth in rest position
FWS = RVD - OVD
anatomical guide planes limit the movement of the jaws
name three
Incisal guidance
Cuspal inclines
TMJ
understand the border movements of the mandible in the sagittal plane
understand this
what is the balanced occlusion concept?
contact on both sides when making excursions
Ideal for edentulous patients -> full dentures
is balanced occlusion possible?
not in dentate patients
