Development of Primary Teeth - Sorenson Flashcards
what is the primate space for each arch?
there is typically a space between the mandibular canine and first molar
there is also a space between the maxillary lateral and canine
What is leeway space?
the sum of posterior teeth lengths in the mesio-distal direction in the primary dentition is greater than the sum of the first 3 posterior teeth in the permanent dentition so when permanent teeth erupts
these each refer to which stage of the developmental staging of the tooth?
initiation
proliferation
histodifferentiation and Morphodifferentiation
apposition and calcification
bud stage
cap stage
bell stage
(didn’t specify)
Tooth development can be seen as early as the ________ week of embryonic life
that early tooth development is recognized because what happens
6th week
epithelial thickening in the area of the future dental arch which eventually becomes the dental lamina
If a dental lamina is disturbed, what may be the consequence?
a missing tooth
T/F The permanent molars, like the primary teeth arise from the dental lamina
Where do permanent incisors, canines, and premolars arise from?
True
from the buds of the primary predecessors
T/F congenital absence of a tooth is a result of a lack of initiation or an arrest in the proliferation of cells
true
____________ ___________ is the result of continuing budding of the enamel organ
supernumerary teeth
if a primary incisor, canine, or molar tooth bud does not form, will the child have the corresponding permanent teeth that erupt underneath?
no
the inner and out enamel epithelium is formed at what stage of tooth development?
proliferation (cap stage)
if the cells during the proliferation stage become more fully differentiated or detached from the enamel organ what happens?
those cells will produce enamel and dentin which results in an odontoma or supernumerary tooth
OR
a cyst can develop
Why would you take out a tooth and its associated odontoma?
because it may stop or slow the eruption of the permanent tooth
In what stage do cells of the dental papilla differentiate into ameloblasts?
Histodifferentiation and Morphodifferentiation (bell stage)
disturbances and aberrations in what stage lead to abnormal forms and size of teeth?
Morphodifferentiation stage (bell stage)
what causes peg laterals
genetics
Amelogenesis imperfecta and dentinogenesis imperfecta problems start happening at what stage?
apposition and calcification stage
any systemic disturbance or local trauma that injures ameloblasts during the apposition phase will cause what?
an interuption or an arrest in the matrix apposition which causes ENAMEL HYPOPLASIA
How does calcification occur?
cells make a small enucleation site called a nidus and precipitation of inorganic calcium salts deposit starting there. (He talked about these growth centers being like a bunch of golf balls)
tooth development starts at about 6 weeks in utero
When do Primary central incisors start to look like a tooth? laterals? canines? Man 1st Max 1st Man 2nd Max 2nd
When do they start to calcify?
All values are values in utero
Centrals: 11 weeks in utero - 14 weeks
Laterals: 13-14 weeks in utero - 16 weeks
Canines: 14-16 weeks in utero - 17 weeks
Man 1st: 12 weeks - 15.5 weeks
Max 1st: 12.5 weeks - 15.5 weeks
Man 2nd: 12.5 weeks - 18 weeks
Max 2nd: 12.5 weeks - 19 weeks
According to some researchers the second primary molar and what other tooth undergo identical patterns of morphodifferentiation but at different times?
second primary molar and first permanent molar
What is the general calcification sequence?
central incisor first primary molar lateral incisor Canine Second Primary molar first permanent molar
T/F the mesiodistal width of the crown of the maxillary central incisor is greater than the cervico-incisal length
true
T/F in the primary maxillary central incisor, the incisal edge is nearly straight even before abrasion becomes evident
true
Max lateral incisor
T/F the outline of the maxillary lateral incisor is not similar to that of the central incisor.
T/F the length of the crown from the cervical to incisal edge is greater than the mesiodistal width
false - it is pretty much the same tooth shape just a smaller size
true
Max canine
T/F the canine has a long, slender, tapering root that is more than three times the length of the crown
False - it is more than twice the lenghth of the crown
Man Central Incisor
T/F The mandibular central incisor is smaller than the maxillary central incisor but its labiolingual measurement is usually only 1 mm less
True
Mandibular lateral incisor
The outline of the mandibular lateral incisor is similar to that of the central incisor but is larger in which dimensions?
all dimensions except labio-lingually
Mandibular Canine
What are the differences between this and the maxillary canine?
the crown is slightly shorter
root is about 2mm shorter
smaller labio-lingually
longer slope of cusp is distal
Max first primary molar
the greatest dimension of the crown of the maxillary first molar is where?
How many roots are there? Are they long or short?
the mesiodistal contact areas
long
What molar is very susceptible to decay in primary teeth?
Maxillary first molar
what tooth looks most like the maxillary second primary molar?
the maxillary first permanent molar
the 2nd primary molar is (larger/smaller) than the primary 1st molar
larger
What is the largest root on the maxillary second primary molar?
the lingual root
HOw many cusps does the maxillary second primary molar have on the buccal?
lingual?
2 on buccal
3 on lingual
Which primary molar doesn’t resemble any of the permanent teeth?
primary mandibular first molar
The primary mandibular first molar has what general shape looking at it from the occlusal view
What about the pulp should we know in this tooth?
rhomboid
the pulp horns are huge
which molars decay all the time in children?
primary maxillary and mandibular 1st molars
in a clinically relevant sense, the pulp horns of primary teeth are largest when?
what causes the pulp to decrease in size?
when they first erupt.
age, function, and abrasion
T/F primary teeth bond to about the same degree that permanent teeth so giving retention form to restorations is not a big deal
False - primary teeth bond worse
T/F
primary teeth have a greater crown to root ratio that permanent teeth
False - the opposite is true
T/F the occlusal tables of primary molars are constricted buccolingually and much narrower mesiodistally when compared with those of the permanent molars
True
enamel and dentin in primary teeth are about what fraction of the thickness of the same layers in permanent teeth?
1/2
the enamel rods of permanent teeth point apically in the cervical 1/3 of the crown. Which direction do they point in primary teeth?
occlusally
The primary molars have a pronounced what?
buccal cervical bulge
T/F contact areas on primary teeth are more narrow and small compared to that of permanent teeth
False - they are more flat and broad
T/F primary teeth are typically more yellow than their permanent counterparts
false - they are typically whiter and a lighter shade
why do roots of primary teeth have more flare?
to accommodate the developing crowns of the permanent premolars
T/F the mesiodistal width of the roots of primary anterior teeth is much narrower than the crown when compared with those of the permanent dentition
True
T/F primary molar roots are relatively longer and more slender than permanent roots
True
which pulp horns are typically closer to the enamel in primary teeth, distal or mesial?
mesial
which primary teeth have larger pulp horns, maxillary molars or mandibular molars?
primary mandibular molars
root canals in primary teeth are extremely tortuous and complex. T/F
true
T/F incisors of the primary teeth have 2 mammelons each and associated developmental grooves
False - they have no developmental grooves or mammelons
because primary molar roots are flared what is more likely to happen to them during extraction?
the roots can break
Roots on primary teeth are (narrower/broader) in a mesiodistal direction than the same roots are in permanent teeth.
narrower
Accessory canal are often present in primary root pulp T/F
true
T/F the pulp chambers are wider in children
true
T/F the root pulp of primary teeth is more ribbon like than in permanent teeth
true
