Mixed Dentition Flashcards
what are the dental arch measurements
-arch width
- arch perimeter
- intercanine distance
how is arch length (depth) measured
at the midline to a tangent touching the distal surfaces of the second primary molars
what are the arch length changes
- lose arch length in the lower arch: lower incisor eruption
- gain length in the upper arch : upper incisor eruption
where is arch width measured from
- between the cusps of the canines in the transverse plane
- between the occlusal grooves of the second primary molars
significant arch width changes from ______ in the ___ arch
primary to mixed; lower
how is arch perimeter measured
from the distal surface of the second primary molar around the arch over the contact points and incisal edges in a smoothed curve
when is the mixed dentition period
6-13 years old
the permanent first molars erupt to the ____ of the primary dentition
distal
describe primary root resorption-> permanent tooth eruption
- crown of the permanent tooth is formed
- the root develops and the primary tooth starts to resorb
- when the root is totally resorbed, the primary tooth exfoliates and the permanent tooth erupts
- the permanent tooth will stop erupting when it reaches the occlusal plane
tooth replacement has variability in:
-sequence
- timing
- position
-numbers
what is the occurrance of congenitally missing teeth
3-5% of population
what are the most common congenitally missing teeth and which is the most common of all
- maxillary lateral incisor: most frequent
- mandibular second premolar
- maxillary central incisor
missing primary tooth =
no permanent successor
what is ankylosis
fusion of the root of a primary tooth to the underlying bone which stops the tooth from erupting
what is ankylosis due to
localized defect during eruption process in periodontal ligament whereby osseous
