4 - Eruption and Occlusion of Primary Dentition Flashcards
what is Baume Type I
2/3rd of primary dentition exhibit generalized interproximal spacing
what is Baume Type II
1/3rd of primary dentition exhibit no interproximal spacing
once established at ___ arches remain spaced or non-spaced over course of primary dentition
36 months
spaced vs. non-spaced arches are related to ___ and not ___
related to: basal arch size
not: tooth mass differences
what are primary spaces
mesial to upper primary canines (maxillary)
distal to lower primary canines (mandibular)
are primary spaces common in Baume I or Baume II?
BOTH!
what refer to the greater mesial distal length of primary canine and molars when compared to permanent canine and premolars
leeway space
leeway space per max quadrant
1 mm
leeway space per mandibular quadrant
2 mm
are all spacing data measurements exact for each person?
NO! this is averaged data and won’t be specific for each patient
if spacing is between 3-6 mm in primary, what percent of transitional crowding
0%
if spacing is less than 3 mm in primary, what percent of crowding
20% w/ incisor crowding
if no spacing in primary, what percent of crowding
50% w/ incisor crowding
if pt has crowded primary teeth, what percent of crowding
100% w/ incisor crowding
flush terminal plane
distal terminal plane
mesial step terminal plane
what is the most common/normal terminal plane
flush! 76% incidence
what are the terminal planes from most to less common
flush (76%) -> mesial step (14%) -> distal step (10%)
when first perm molars erupt [mesial, distal] to primary molars, their occlusal relationship is initially determined by primary molar relationship
DISTAL
final permanent molar relationship is result of what effects
- early mesial shift
- late mesial shift
- differential mandibular growth
what is the closing of interdental space between molars prior to eruption of perm molars
early mesial shift
what occurs due to eruption path of permanent molars which guide on distal roots of primary second molars
early mesial shift
at what age does early mesial shift occur
~4 years