Flashcards in Primary tooth morphology Deck (56)
What are early problems that can affect children even before they are born
- gingival cysts
- congenital epulis
- natal or neonatal teeth
- eruption cysts
What are gingival cysts also known as
epstein's pearls or bohns nodules
what do gingival cysts look like? Are they a problem?
small white 'pearls'
What does a congenital epulis look like? What happens to them? Are they a problem?
a massive red bulge out of the mucosa.
will shrink as child grows or can be removed. Not dangerous
What problems can natal or neonatal teeth cause?
do they tend to be removed?
can be mobile and cause ulcers, not got as strong roots. Sometimes are taken out if a big interference but otherwise not.
What does an eruption cyst look like? What causes it? Is it a problem?
a blue blob on the mucosa, blood has got in there, no it will resolve
what is the notation of an upper right second primary molar?
What is really important about primary tooth notation
upper right E
never use numbers and letters together
When do teeth start to form?
week 5 of intrauterine life
When does hard tissue start to form
week 13 of iul
What are the calcification dates of the maxilary central incisor
start cal 13-16 weeks iul
crown complete 1.5 months after birth
eruption 8-12 months
root complete 33 months
(see welbury text page 12)
What is the chronology of the maxilary second primary molar
(hard tissue formation, crown formation, eruption, complete root formation)
hard tissue formation 16-23 weeks iul
crown formation complete at 11 months after birth
eruption between 25-33 months
complete root formation 47 months
How might the process of calcification cause defects in primary teeth
- systemic disturbances during calcification can lead to defects in the enamel which was forming at that time
- defects in the primary dentition (which are not hereditary) are most likely the result of a difficult pregnancy for the mother/ birth complications
How much of central incisors are calcified at birth
How much of lateral incisors are calcified at birth
How much of primary canines are calcified at birth
How much of first primary molars are calcified at birth
How much of second primary molars are calcified at birth
How much of permanent molars are calcified at birth
tip of cusps
what are the possible theories behind tooth eruption
- cellular proliferation at the apex of the tooth
- localized change in blood pressure/ hydrostatic pressure
- metabolic activity within the PDL
- resorption of the overlying hard tissue
why does resorption of the overlying hard tissue occur
due to enzymes in the dental follicle
what does the dental follicle look like on a radiograph?
a dark halo round the unerupted tooth
what process is essential for the process of tooth eruption
however, it is not necessary for the tooth to erupt to cause resorption of bone
what role does the dental follicle play in tooth eruption
is activated to initiate osteoclastic activity in the alveolar bone ahead of the tooth and clear a path for tooth eruption
(once crestal bone has been breached the follicle is likely to play a lesser role)
how does eruption occur
- occur gradually
- stops when the tooth comes into contact with something-usually the tooth of the opposing arch
- continues throughout life to compensate for vertical growth of the jaws and tooth wear
what is the order of eruption (general rules)
lowers before uppers except lateral incisors
central incisor, lateral incisor, first primary molar, canine, second primary molar
what is the eruption dates for the lower central incisor
what is the eruption dates for the lateral incisors
what is the eruption dates for the 1st molars
what is the eruption dates for the canine