Flashcards in Lecture 7 Deck (13):
what is balanced occlusion and when is it preferred?
bilateral and balancing contacts in lat and protrusive movements-->best for removeable prostho (keeps dentures from falling out)
what is unilateral eccentric contact
replaced balanced occlusion; best for dentate patients
what are the most important things to think about when designing or changing occlusion?
-stability of the bite/movement
-even distribution of forces
-non-pathological (wear, pain)
if CR = CO (MIP), then musculoskeletal stability is acheived = does not create pain; that's why we want to help patients with TMJ have MIP = CR to try to eliminate it as an etiologic factor
very important -- if CR produces unstable contacts, neuromuscular system will find a new position; MSS can only be present if also in harmony with stable occlusion
unstable occlusion = force is not balanced; one condyle may be driven posterior into the fossa
job of the PDL?
to convert pressure forces into tensile forces
the PDL is collagenous tissue that runs OBLIQUELY and occlusal
how can bruxism lead to alteration in bone?
is a lateral/destructive force on teeth that cannot handle it (posts) --> PDLs convert pressure to tensions (osseous formation) and compression (bone resorption)
why is canine guidance important in lateral movements?
-has the longest root
-small crown:root ratio
-thick buccal bone
- decreased in activity and number of muscles active when in contact
why is any contact during laterotrusive movements not ideal past the MB of the upper 6?
too close to the fulcrum-- increased forces
anterior teeth are meant to take protrusive/lateral movements (smoother surfaces, glide easier, longer roots, etc) while posteriors are better at taking vertical movement (mutually protected occlusion) because they are bigger, thicker, more resilient