Primary Tooth Morphology and Eruption Flashcards
what early problems can arise in babies/
- gingival cysts
- congenital epulis
- natal or neonatal teeth
- eruption cysts
what are gingival cysts formed of? are they a cause for concern?
- formed of keratin
- not a problem
what are teeth present at birth referred to?
natal teeth
what are neonatal teeth?
teeth that erupt in the early days/weeks of life
what teeth tend to be natal/neonatal?
lower primary central incisors
when would natal/neonatal teeth require treatment?
- causing ulcers
- affecting mum when feeding
- very mobile teeth
what is an eruption cyst?
- a cyst overlying where the developing tooth is about to erupt
- they look blue because it is filled with blood
- resolve on their own
what is the upper right quadrant of the primary dentition in FDI notation?
5
what is the upper left quadrant of the primary dentition in FDI notation?
6
what is the lower right quadrant of the primary dentition in FDI notation?
8
what is the lower left quadrant of the primary dentition in FDI notation?
7
when do teeth start forming?
week 5 of intra-uterine life
when does hard tissue formation start?
week 13 of intra-uterine life
what is the eruption and root completion dates for a primary upper incisor?
- eruption 8-12 months
- root completion 33 months
what are the eruption and root formation dates for a primary upper second molar?
- eruption = 25-33months
- root formation = 47 months
defects in the primary dentition (which are not hereditary) are most likely due to what?
a difficult pregnancy for the mother or complications at birth
what is a general rule in the order of eruption for the primary dentition?
the sequence tends to be
- central incisor
- lateral incisor
- first primary molar
- canine
- second primary molar
do lower or upper teeth erupt first?
as a general rule, lower teeth erupt before upper (the exception is the LATERAL INCISORS)
what is normally the first tooth to erupt?
the lower central incisor at around 4-6 months (quickly followed by the upper CI)
what teeth tend to erupt at around 7-16 months?
the lateral incisors (52, 62, 72, 82)
*roughly when does the first molar tend to erupt?
13 - 19 months
what tooth tends to erupt at around 16-22 months?
the canines
when do the 2nd molars erupt?
15-33 months
when is primary dentition complete by?
approx. 2 and a half - 3 years
how are primary incisors different to permanent incisors?
primary incisors are smaller in both their crown and root proportions
how are primary molars different to permanent molars?
- primary molars are wider mesiodistally
- primary molar crowns are more bulbous
what is an interesting anatomical feature of the first primary molars?
they have a prominent mesiobuccal tubercle
what anatomical feature is found on upper second primary molars?
transfer ridge
what anatomical features does the lower second primary molar have?
three buccal cusps
how are the primary roots different to the permanent roots?
the roots of the primary teeth tend to be narrower when compared to permanent counterparts
what is interesting about the primary pulps?
the pulp chambers of the primary teeth are relatively LARGE in proportion to the crowns that surround them
what is interesting about the pulp horns in the primary dentition/
the pulp horns of primary teeth extend high occlusally (placing them closer to enamel)
describe the root canals of primary teeth:
tend to be ribbon shaped with multiple interconnecting and accessory canals
when primary teeth are in occlusion, what is typically seen?
anterior spacing (which is desirable)
why is primary spacing desirable?
to avoid crowding in the permanent dentition
what is the mixed dentition stage?
it begins from the time the first permanent tooth erupts, until the exfoliation of the last primary tooth
when does the mixed dentition stage normally occur?
6 - 11 years
How long do typical roots take to fully develop after eruption?
3 years.
