Autumn quiz II: Physio of permanent teeth Flashcards
what does masticatory apparatus function depend on
-musculature and nervous system depends on -skeletal structures -forces generated by musculature -temporal mandibular joint function -morpholgoy of the teeth -angulations of the teeth -anatomy of supporting structures -periodontium
how can improperly formed arches impact function
- speech
- chewing efficiency
- restorative procedures
what occurs with a NARROW arch?
- if dental arch is too narrow and patient is young the teeth may correct themselves a bit. some teeth may be selected for extraction to allow more room for the other teeth
- frequently braces or other corrective measures like spacers are needed to widen the arch
what occurs with a wide arch?
-teeth may come in with large spaces between them. braces can often be appleid in order to shift the teeth forward into proper position
when does a tapered or v shape arch occur
- maxillary usually
- due to pathologic narrowing of the anterior palate. less commonly could be due to severe thumb sucking habit
where do the canine and first molar sit with respect to ideal curvature in maxilla
they sit facial to the ideal curvature
where does the canine sit with respect to ideal ellipse in mandible
facial to ideal ellipse
what four forces does stability of and occlusion and maintenance of tooth position depend on?
- eruptive forces
- occlusal forces
- lip and cheek pressure
- tongue pressure
what forces do restorations and extractions alter
restorations; occlusal
extractions; all forces
whats a root axis line
imaginary line that divides root to halves md or fl at cervical line
from a frontal view what are the angles of central incisors? sagittal view?
fronta;
- Max MD tilts distally less than 2 degrees
- Mand central incisors tilts medially (all ant) (MD) less than 2 degrees also
sagittal:
- max FL ; less than 28 degrees
- mand FL less than 22 degrees
frontal/sagittal view; lateral incisor angles?
frontal:
- maxillary ; MD less than 7 degrees,
- mand less than 0 degrees?
sagittal:
- max less than 26 degrees FL
- mand; less than 23 degrees fl
frontal/sagittal views; canines
frontal:
- maxillary; MD less than 17 degrees
- mand; md less than 6 degrees
sagittal:
- max; FL less than 16 degrees
- mand; fl less than 12 degrees
which two teeth form contact most like a contact “point”
canine and first premolar in both arches
where are contact points in anteriors vs posteriors generally
anteriors; contacts normally centered faciolingually
posteriors; contact centered OR located buccal to center BL direction
what are general trends of interproximal contact areas?
- increase in size more cervically you move from anterior to posterior
- distal contact is usually more cervically located than the mesial contact
whats teh function of interproximal contacts?
- stabilize arches
- prevent food from slipping between teeth
- define embrasures space and help direct blood flow
- pattern during mastication
what stops third molars or second molars from drifting distally?
bc of lip, cheek, and tongue pressures directed anteriorly
what occurs if inter-proximal contact areas are lost
-gingiva inflammation and irritation bc food is forced beyond contact area
whats the base of the triangle of the interproximal space?
-base is alveolar process
how large is the separation between enamel and alveolar bone in normal occlusion
1-1.5 mm
what are all of the types of embrasures
- buccal/labial (seen from above)
- lingual
- incisal/occlusal
- gingival/cervical
whats the function of embrasures
- creates a spillway for excape of food during mastication
- prevents food from being forced thru contact areas
whats lamina dura
thin compact bone layer of alveolar crest
