32. Orthodontics III Flashcards
Conditions associated with supernumerary teeth ➡️ “Delayed eruption”
- Gardner’s
- Down’s
- Cleidocranial dysostosis
- Sturge weber syndrome / Encephalotrigeminal angiomatosis
Other term for Gardner’s
Familial colorectal polyposis
Supernumerary teeth = Impacted (Clinical exam: Few teeth present) ; with polyps in rectum
Gardner’s
Ddx of garners
- with freckles
- # teeth
- polyps
Peutz jeghers syndrome
HEREDITARY INTESTINAL POLYPOSIS
Portwine stains - follows CN V!!
Sturge weber (encephaloTRIGEMINAL angiomatosis)
BQ: What is the most common supernumerary teeth?
Mesiodens
BQ: What stage of tooth development does supernumerary occur?
Initiation stage
BQ: How many teeth are present in the radiograph of a newly born child?
24
20 deciduous/4 perm 6s
Stage of tooth dev: determines # of teeth; (Supernumerary)
Initiation stage
Stage of tooth dev: morphodifferentiation
Shape/maturation
Bell stage
Stage of tooth dev: Appositional stage (-deposition of enamel and dentin)
Bell stage
Stage of tooth dev: Histodifferentiation
Bell stage
Enamel organ gives rise to:
Enamel
Dental papilla gives rise to:
Dentin
Pulp
Dental SAC / FOLLICLE gives rise to:
Cementum
PDL
Alveolar bone
Ameloblasts are derived from?
Inner enamel epithelium
Cells that line dental pulp
Odontoblasts
Which is first to form: Ameloblasts or Odontoblasts?
Ameloblasts ➡️ Odontoblasts
*remember A is first in the alphabet
Which is first to form: Dentin or Enamel?
Dentin ➡️ Enamel
First in the alphabet
BQ: OEE + IEE =
REE (reduced enamel epithelium)
BQ: Initial membrane / barrier of enamel
Ree but in erupted tooth already
Nasmyth’s membrane or Primary enamel cuticle
BQ: Oee + IEE in the “cervical area” forms:
Cervical loops
Cervical loop gives rise to:
HERS
Responsible for ROOT development
✅ Shape and # of roots
HERS
HERS gives rise to:
Epithelial diaphragm
Responsible for shape and # of APEX
Epithelial diaphragm
Remnant of HERS
Epithelial rest of malassez
Can enamel regenerate? Dentin? Cementum?
Enamel - cannot!!! (Far from pulp = no blood supply)
Dentin and Cementum ✅
BQ: what is the Indication for serial extraction???
space indicated
Answer sa boards: 8mm
When to exo:
C
D
4
C - 8
D - 9
4 - ASAP
Key to success of SERIAL EXTRACTION (CD4)
Extract 1st PM before PERMANENT CANINE erupts!!!!
Failure of Serial exo is common to: Maxilla or Mandible??
Failure: Mandible
61234578
Successful serial exo is common to: Maxilla or Mn?
Success: Maxilla
61245378
Difference between Md width of CDE and 345
Leeway space
Formula for leeway space
Leeway space = CDE - 345
BQ: Leeway space is: a. Positive B. Negative C. Zero D. Nota
Positive!!!
Leeway space in the MAXILLA
- 8mm - both sides
0. 9mm - one side
Leeway space of MANDIBLE
- 4 - both sides
1. 7 - one side
Easiest orthodontic tooth movt
Extrusion
Most difficult ortho tooth movt but LEAST force required
Intrusion
Most common ortho tooth movt
Tipping
Only movt of removable appliances
Tipping
Center of rotation in ROTATION
Long axis
Center of rotation of incisors during TIPPING
2/3 apicocervically of root
Or (1/3 cervicoapically of root)
Center of rotation of MOLARS
Bifurcation
Extrusion and Intrusion
Rotation -
Cor -
No rotation = NO center of rotation
BQ: Best rotational force
Coupling force (Couple)
Otho movt that has greatest force required
Translation (“bodily movt”)
- no center of rotation!!
Cells present on the side toward which tooth is being moved / TENSION SIDE!!!!
Osteoclast
tension side= bone resorption
Cells present of the side of the root from which the tooth is MOVED / PRESSURE SIDE!!!
Osteoblasts
Pressure side = bone apposition
BQ: Best force for ortho
Light continuous force
{ Light: frontal resorption = faster
Heavy: undermining resorption }
