Occlusion Flashcards
definitions
mandibular movement and the resulting contacts of maxillary and mandibular teeth from these movements
intra-arch alignment
with in the same arch
interarch alignment
with opposing arch
Intra-arch alignment characteristics
- contact areas and tooth form
2. embrasures
axial positioning of intra-arch alignment
relationships created parallel to and with the long axis of the teeth
Curve of spee description and function
Anterior-posterior
description-canine tip to DB cusp of maxillary second molar
function-distribute occlusal forces
curve of wilson descript. and function
medial to lateral (lingual inclination)
descript.-inclination of teeth
function-distribute occlusal forces
intra-arch alignment variations
buccoversion-buccal to normal arch form
linguoversion-lingual to normal arch form
tosoversion-tooth rotate/turns in an otherwise normal position
Supraversion
supereruption due to lack of opposing tooth
infraversion
ankylosed-tooth does not reach occlusal plane. Generally primary teeth that are retained
mesioconversion
loss of one tooth causing posterior tooth to drift to midline
distoversion
tooth moves away from midline, usually pre-molars
Centric relation
bone dictated position, condyle and temporal bone (interarch)
Centric Occlusion
tooth dictated, position where teeth fit together best (interarch)
Elevation 2 movements
- CR
2. CO
Lateral movements
- canine guidance/group function; posterior teeth open up when canines touch
- working side; when moving mandible to the right side, that side is the working side,
- balancing side; when the mandible is moved to the right side, the left side becomes the the balancing side
protrusion movements
- anterior movement
- determined by temperal bone and anterior teeth shape
- posterior teeth should not touch
retraction movements
- opposite of protrusion
2. only anterior teeth contact
4 characteristics to ideal occlusion
- CR=CO
- canine protection in lateral movements
- no balancing side interference
- no posterior interference in protrusion
2 traits of premature contacts
- contact before CO or guided CR
2. instability in patients occlusion
Articulation of a complex hinge joint is what class lever system?
class 3
ligaments only restrict..
envelope of motion. no ability to move mandible
3 traits of muscles
- create all mandibular movement
- CR; posterior position in the envelope of function where mandible should be during function
- CO; teeth create a muscle memory, and muscles take teeth where they fit best
overjet characteristics
- horizontal overlap
- avoid biting soft tissues
- protects anterior incisal edge
- allows for posterior maximal intercuspation
underjet
maxillary anterior teeth are lingual to mandibular anteriors
overbite characteristics
- usually with in the incisal 1/3
- creates disclusion of posterior in protrusion
- excessive lingual attrition
- deficient open bite