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
what is the result of ankylosis in mixed dentition
occlusal level of ankylosed tooth does not keep up with vertical level of adjacent teeth
what is the treatment for ankylosis
- monitor these teeth - 50% will self correct
- if they fail to exfoliate- extract the tooth to avoid damaged to the permanent dentition
describe the variability in mixed dentition
high