Lec.5 Morphology of the primary teeth(1).pdf

Morphology of the primary teeth

1. Department of:
HERE
By Doctor: Rana Al-Mohana
2022-2023
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2. Department of:
HERE
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3. 020-2021MaxillaryCentralIncisor
•Onlycrownthathasagreater
mesiodistalwidththanheight
•Prominentcingulum
•Straightincisaledge
MaxillaryLateralIncisor
•Similarformtocentral
•SmallerandDIanglerounded
Primary teeth morphology
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4. Department of:
HERE
Primary teeth morphology
MandibularCentralIncisor
•Symmetricallyflatwhenviewedfrom
buccal.
•Crownabout1/3lengthofroot.
•Cingulumlessprominent.
MandibularLateralIncisor
•Similarformtocentral
•Usuallylonger
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5. Department of:
HERE
MaxillaryCanine
•Crownconstrictedatcervicalregion.
•Welldeveloped,sharpcusp.
•Rootislong,morethan2Xcrown.
MandibularCanine
•Similarformtomaxillary
•Crownshorterandnarrowerlabiolingually
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6. MaxillaryFirstMolar
•Uniqueappearance.
•Threecusps-MB,DBandLingual.
•ProminentMBcervicalbulge.
MandibularFirstMolar
•Alsouniqueinappearance.
•Fourcusps-MB,DB,MLandDL.
•ProminentMBcervicalbulge.
•Transverseridge.
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7. Department of:
HEREMaxillary2ndMolar
•ResemblespermanentMaxillaryfirst
molarbutsmaller
Mandibular2ndMolar
•Resemblespermanentmandibular
firstmolarbutsmaller7

8. Department of:
HERE
upper
lower
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9. Department of:
HERE
Roots of primary teeth
•Roots of anterior teeth are narrower
mesiodistally
•Posterior teeth have longer and more
slender roots in relation to crown size
•Molar roots flare more as they
approach the apex
•Apical foramina may be larger and
accessory canals often larger and
more numerous
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10. Pulps of Primary Teeth
•Relativelylarger
•Pulphornsareclosertotheouter
surface
•Greatvariationinsizeandlocation
•Mesialpulphornishigher
•Pulpchambershallow
•Usuallyapulphornundereachcusp
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11. Department of:
HERE
Average dimension of primary molars from exterior
surface to the periphery of the pulp chamber
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12. Procedures in Primary Teeth:
RestorativeDentistry:
•Enamel is thinner, therefore
modifications are necessary in the
cavity preparation.
•Broad contacts need to be restored.
•Beware of the mesio-buccalpulp horn.
•May need to do SSC if both proximal
surfaces involved.
•Preserve the buccalcervical ridge to
obtain mechanical retention for SSC.
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13. Department of:
HERE
Question
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14. Department of:
HERESurgical Procedures:
•Conicalanteriorrootsfacilitate
easyremoval
•Flaredrootsofthemolarsuse
cautionaspremolarbudsare
locatedbetweentheroots
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15. 15

16. primary
permanent
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17. Pulp Therapy:
Pulpotomy:
•bewareofperforations.
Pulpectomy:
•Difficultonmolarsduetotortuous
andirregularpulpcanals
•Bewareoftoothbuds.
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18. Morphological difference between
primary and permanent teeth
Thecrownsofprimaryteeth:
•areshorter
•haveanarrowerocclusaltable
•haveamorepronouncedcervical
constriction
•havethinnerenamelanddentinlayers
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19. •haveenamelrodsthatrunin
aslightlyocclusaldirection
fromtheDEJ
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20. •havebroadflatcontactareas
betweenprimarymolars
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21. •have nearly the same mineral
content as permanent teeth
•have a lighter, more homogeneous
color
E6
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22. Rootsofprimarymolars:
•arelongerandmoreslenderinrelation
tocrownsize
•aremoreflaredastheyapproachthe
apexinordertoaccommodatethe
developingpermanenttoothbuds
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23. 1 2
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24. Keys to differentiating primary
and permanent teeth:
Color primary teeth white and opaque
Size and contours
Depth of anatomy
Age of child
Location of teeth (counting)
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25. Size
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26. Depth of anatomy
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27. Department of:
HERE
A
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30. c
B
1
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35. What if everything got mixed
up and you can’t tell which
one is primary and which is
permanent
?
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36. Thank U
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