border movements Flashcards
maximal intercuspal position
the complete intercuspation of the oppositing teeth independent of condylar position
-REPRODUCIBLE if sufficient teeth present
physical rest position
position of mandible when muscles are in equilibrium and condyles are neutral
what is the interocclusal distance in physiologic rest position
freeway space (2 - 4 mm)
centric relation
condyles articulate with thinnest avascular position of disc
-anterior superior position on articular eminences
centric relation
- independent of tooth contact
- PURELY REOTARY MOVEMENT
centric occlusion or centric relation occlusion
occlusion when mandible is in centric relation
ideal occlusion
centric relation = maximal intercuspation
posselt envelope
path of movement when traces at the tip of the mand central incisor
protrusion
condyle moves forward and down
vertical opening
- purely rotation (12-20mm)
- then translation and rotation (5-6mm)
working side in lateral excursion
lateral, latero-post, or latero-ant
non-working side in lateral excursion
forward and medial
-follows curved path
lateral movement in direction of working side
bennett movement
bennett angle
angle formed by sagittal plane and path of NW condyle
protrusive movement is guided by
incisors
lateral movement is guided by
canines
in static occlusion, what protects what
post protects anterior
in dynamic occlusion, what protects what
anteriors protect posteriors
curve of spee
curve from tip of canine to DB cusp of 2nd molar
curve of wilson
mediolateral curve that contacts B and L cusp tips of each side of the arch
curve of wilson shows the inward inclination of the
lower posterior teeth
*L cusps are lower than B cusps
because of the inward inclination of the lower posterior teeth
the upper teeth have an outward inclination, so the L cusps are higher than the B cusps
what motion does curve of spee allow
protrusive movement of mandible
what motion does curve of wilson allow
movements for chewing
plane of occlusion
plane that covers incisal edge of incisors and tip of DB cusps of 2nd molars
-includes curves of spee and wilson and incisal plane
