intro to occlusion Flashcards
occlusion
manner in which the teeth come together when closing the jaw
relationship between teeth when moving the mandibel
how the teeth should work upon closing
posterior teeth contact
- anterior light contact
why should posterior teeth take the load
large SA
capabable of taking load and distributing it
ICP
relationship between mx and md when the teeth are in maximum intercuspation(when teeth are together)
centric relation
the most anterior supeiro position of the condule disc within the glenoid fossaa
relationship between mx and md (not to do with teeth)
RCP
first point of contact when mouth is closing
during sideways movement
posterior teeth seaprate
canine dictates movment
canine guiande
resists sideways forces due to shape
root is very long
distant from hinge and muscle
during forwards movemet
contact on protrusion
anteerior teeth disclude the posterior teeth
palatal surfaces of upper anterior teeth dicate md movemtn
teeh classiications
class 1 class 2(2 divisons) class 3
class 1
the mesiobuccal cusp of the upper first molar occlusdes in the buccal groove of the permanent md 1st molar
lower incisor occlides just below the upper incisor cingulum plateau
class 2
- Lower incisor occludes behind upper incisor cingulum plateau
- upper incisors are the correct inclination or proclined, overjet is increased
- Upper central incisors are retroclined
- The mesibuccal cusps of the permanent maxillary first molar occludes mesial to the buccal groove of the permanent mandibular first molar (lower molar tooth is further back
divison 1 and 2 of class 2
div 1 overjet
div 2 overbite
overbite
- Upper central incisors are pro lined
- Lower incisor occludes behind the upper incisor
- large overbite
class 3
Lower incisors occludes in front of the upper incisor cingulum plateau
- or edge to edge
The mesiobuccal cusp of the permanent maxillary first molar occludes distal to the buccal groove of the permanent mandibular first molar
anteior open bite
only posteiro teeth contact
large amounts of space between anteiror teeth
movement of manible dictated by
- Position of the condyle in the fossae
- Condylar pathway along the articular eminence
- Teeth interferes with this border movement
protrucisve excursion condyle movment
condyle moves forwards and downwards
working side
where there is contact and where the lower teeth are moving to that side
ideal occlustion
- CR= ICP
- forces directed through long axis of the teeth
- Anterior guidance in protrusion
- Canine guidance in lateral excursion
- Mutual protection
group fucntion
all of the teeth contacting as we move to the working side, group of teeth functioning rather than canine guided when going sideways
balanced occlusion
vartificial, eg in dentures to keep stable attempt to make the sides balance and for the teeth to mesh together in each excursion