Pediatrics Flashcards
Location of PEDO mandibular foramen?
closer to occlusal plane (7mm above), more distal, overall mandible is less developed = higher success of IA nerve block.
Max PEDO dose of LA?
2 mg/lb (300 mg max)
Class II amalgams are retained with?
dove tails
Extension for prevention are used only with ___ restorations
amalgams (not composites)
Class II preps are less than ideal and deep due to ___
cervical constriction
PEDO SSC do not require a ledge in the prep, why?
- The ledge will prevent seating of the crown all the way.
- We want the margin to be at or below the gingival margin.
- SSC require 1-1.5 mm Occlusal (sometimes B-L to remove bulge) reduction.
Primary tooth dentin is ___ that of adult
1/2
Class II preps in PEDO teeth do not need what?
Gingival bevel bc the enamel rods converge occlusal.
There must be __ % of demineralization in teeth to be seen radiographically
30-60%
Remember: Primary Teeth have more organic content than adult teeth
Compomer vs Hybrid vs resin modified GI
- GI is a weak material.
- Hybrid is stronger than GI, and gives more Fl than compomer
- Compomer is more like composite, thus is the strongest, but doesn’t release as much Fl and is considered the least caries resistant.
formecresol dilution for pulpotomies
20%
Risk of using CaOH in direct pulp cap?
pulp irritation. Thus, do pulpotomies. Only to DPC if tooth will exfoliate in 6 months.
Pulpotomy procedure:
vital tooth, asymptomatic, healthy pulp!
- hemostasis of pulp with formecresol and a cotton pellet for 5 minutes
- Obturate/fill pulp chamber with ZOE
Most ankylosed primary tooth (over-retained)
Mand 1M
Tx if accidentally EXT a permanent tooth bud
replant ASAP with pressure and sutures
A PANO is recommended at what age?
6 y/o
Enamel thickness of primary vs permanent molars
Primary = 1 mm Permanent = 2.5 mm
Primary teeth characteristics:
- more M cervical ridge (tell L from R)
- longer, slender roots
- Roots are Narrow MD, Broad Bucally-lingually
- little to no root trunk
- v. divergent roots and less curved
- less anatomy (shorter cusps, grooves, pits)
- cementum is thinner
- ST is flabbier, more red, more rolled FGM, PDL fibers run in parallel to the teeth
- bone has fewer trabeculation, more BM and has a flatter crest
- Thin lamina dura and larger pockets
- not as wide attached gingiva (due to labial eruption)
Leeway space
- primary canine to 2M and permanent canine to 2PM
- Max anterior primary teeth are 75% the size of their permanent teeth
- Mand anterior primary teeth are 6mm narrower MD than their permanent teeth
- Primary molars are wider MD
- Maxilla 1.5 mm per quadrant.
- Mandible 2.5 mm per quadrant
Primate space
MAX primary lateral incisor and primary canine
MAND primary canine and primary 1M
most common missing permanent teeth:
3M > Mand 2PM > Max LI > Max 2PM
Most common primary missing: Max LI
remove ankylosed teeth via
sectioning the tooth
Space maintainer for:
Adult 1M is lost before the eruption of adult 2M
nothing. 2M will medially drift into 1M space.
NOTE: no space maintainer is needed if adult tooth will erupt soon (look at radiographs for root development)
Space maintainer for:
Primary 2M is lost
- Always use a space maintainer until Adult 2PM arrives.
- The most rapid loss of AP spread is due to mesially tipped/rotated adult 1M after early removal of primary 2M.
Cleft lip and Palate
Plates develop 4-5 weeks gestation
Secondary palate developed at 9 weeks
Upper Lip = 2xmedial nasal swellings + maxillary swelling
Palatal shelves from the maxillary process orient from a vertical to horizontal position as the tongue descends.
The secondary shelves fuse with each other and the Primary plate (= maxillary + mandibular process) to form he palate.
Lip is more common in males (Left > Right)
Palate is more common in females
Most impacted tooth
Max. canine
- There is an association with impacted canines and missing or shortened lateral incisors, given the the LI distal roots guide the canines into position.
- Impacted teeth must be brought down through keratinized tissue, not mucosa
Arch length
Max: 128 mm (longer)
Mand: 126 mm
Jaw growth in width is completed before adolescent, but length continues
both jaws: Width (before adolescent) then length then height (after adolescent) is completed
Tooth eruption direction
occlusal and buccal
EXCEPT max and mand incisors which come lingually
baby bottle disease order of decay
- Max ant.
- Max post.
- Mand post.
- Mand ant.
ECC is defined as:
- any cavitation under 3 y/o
- more than one DMFT score in the anteriors
- DMFS > 4 in 3 y/o
- DMFS > 5 in 4 y/o
- DMFS > 6 in 5 y/o
Root development
- cervical loop of the enamel organ (epithelium) → Hertwig root sheath
- Erupts: 2/3 of root formed
- Fully formed 3 years post eruption
- Accessory canals are formed by breaks in root shealth when dentin is deposited
Calcification
- All primary teeth begin 14-24 weeks in utero
- Permanent Max and Mand 1M begin calcification at birth and erupt at 6-7 y/o
- Shape of tooth is determined by the ectoderm (enamel). Mesoderm distracts pulp and dentin.
cementum
- Developes from dental sac AFTER Hertwigs sheath is disintegrated.
- Calcified
- Avascular
Types
- Acellular = primary cementum = High [sharpey] fibers = attached to the root
- Cellular = secondary cementum = made only after tooth reaches the occlusal plane = more irregular with cementocytes = less calcified = smaller [sharpey]
- Repair occurs on cellular cementum that is NOT in perio pockets or exposed
- Cementum deposits is most at apex to compensate for eruption.
Lobes
- It’s a growth center = primary centers of calcification
- Represented as cusps on posteriors or cingulums and mamelons on anteriors
- Minimum number of 4
Always separated by:
o Developmental grooves = Posteriors
o Developmental depressions = Anteriors
Anteriors 3 labial + 2 lingual (cingulum)
PM 3 B + 1 L (NOTE: Mand 2PM = 3B + 2 L)
1M 5 lobes
2M 4 Lobes
3M 4 Lobes
6 year molars are what?
Permanent 1Ms
Thus, a 6 y/o would have all 20 primary teeth and 4 x 1Ms
A 7 y/o would have 18 primary teeth, 4 x 1Ms, and #24,25
Monitor a splinted tooth for how long?
Monitor Indirect pulp cap for how long?
Monitor a fully avulsed tooth that is splinted?
Splinted: 3 months
Indirect pulp cap: 3-4 months
Avulsed tooth: 2 weeks, or risk ankylosis
Hypocalcification is most common in which teeth?
Mand. incisors
Avulsed teeth protocol
- 1 Hr window or risk external resorption
- Splint for 2 weeks (or risk ankylosis) → RCT with CaOH that is replaced every 3 months for 1 year → Permanent gp obturation
- Antibiotics only used with replants in 1 Hr of injury
If over 1 Hr, do RCT outside the mouth, soak in 2.4% Acidulated Fl solution to limit resorption, and splint for 4 weeks
- Replants fail mainly due to external root resorption.
Main cause of failure for replanted teeth?
External root resorption
Most common teeth that ectopically erupt
Max 1M > Max C > Mand C > Mand 2PM > Max LI
Fluoride use
No effect hydroxyapatite → decrease enamel solubility
- Remineralization
- Anti-bacterial
- Low [Fl] → stops glucosyltransferase and polysaccharide formation
- High [Fl] → topical treatment → directly toxic to bacteria
- Proximal tooth surfaces benefit the most from Fl
- Excreted in kidenys
Rule of 6 = No supplemental Fl given regardless of high risk
for over 0.6 ppm of Fl.
Chronic Fl toxicity shows up in bones (skeletal tissue) as osteosclerosis and dental fluorosis (only during calcification stage of tooth development)
- Lethal F = 500 mg (or 5mg/kg of body weight)
- Tx: Ca = Milk will decrease Fl absorption (in acute Fl toxicity) by increasing pH.
- 8.2 oz tube = 232 mg Fl
Topical Fl’s most stable product is fluoroaptite
Water fluoridation is considered both systemic and topical application
Anyone with 2ppm fl + in their water supply should not use the water
Cariostatitc effects only occur when tooth calcification is occurring.
fluorosis can occur even in adult teeth
Hypercementosis frequently occurs where?
PM > 1M > 2M
- usually confined to apical half
- vital teeth
- asymptomatic
- unbroken PDL on x-rays
- Seen in Paget’s disease, gigantism, acromegaly and thyroid goiters
Dens in dente and dens evaginatus
Dens invaginatus
- Invagination of enamel organ during formation
- Most common in Max LI
Dens Evaginatus
- extra cusp (has all three layers of teeth)
- talon cusps in incisors
- Evagination of inner enamel epithelium cells
Taurodaunt
Extremely large pulp chambers with short roots
- from failure of the proper level o horizontal invagination of Hertwig epithelial root sheaths
Which type of fluoride is most beneficial for root caries (and sensitivity)?
NaF
- Precipitates calcium fluoride crystals in the open dentinal tubules
Sealants
molars benefit the most, but bicuspid pits and fissure show longer retention
- Sealants mimic unfilled resins, more than filled
