01.09, anatomy, SS crowns, pulpotomy, restorative Flashcards
Primary compared to permanent dentition:
-size, color, mineralization, thickness of dentin and enamel, pulp cavities
- Primary teeth;
- smaller in size
- whiter in color
- less mineralized
- dental and enamel thinner (1/2)
- crowns constrict at CEJ
- pulp cavities are larger
primary incisors:
O Incisors have no mamelons
O Roots of anterior teeth bend labially
O Fewer grooves and depressions
Primary Molars
O Roots are flared, thin, and slender
O Maxillary molars have 3 roots- MB & DB & P
O Mandibular molars have 2 roots- M & D
O Contacts broad and flat
O Narrower occlusal table
O In cervical area, the enamel rods slope occlusally (permanent slope cervically)
which primary teeth have a transverse ridge?
mandibular first molars (maxillary second molars have oblique ridge)
primary molar overview
O Maxillary second primary molar looks like mandibular first permanent molars (#3 & 14)
O Mandibular second primary molar looks like mandibular first permanent molar (19 & 30)
O First primary molars are unique
which rubber dam clam is best for primary molars?
W8A or 8A, can even be used on partially erupted teeth, can also be used for primary molars that are not fully erupted
which rubber dam clam works well for permanent first and second molars which are not fully erupted?
14A
method for preparing the rubber dam in pedo
Slit dam isolation, less isolation, but easier to place
-clamp is place first, then the rubber dam assembly
what is the most common mistake in the restoration of primary teeth?
over-extension of the prep
mandibular first primary molar class I prep
kidney bean shape (remember 1/3 intercuspal distance)
proximal box of a class II prep in primary dentition
floor is rounded bc of the direction of the enamel rods
types of matrix bands used:
-Condit’s Tee Bands (most popular), no need for extra intraoral apparatus
most common errors
A- Failure to extend occlusal outline into all susceptible pits and fissures.
B- Failure to follow the outline of the cusps.
C- Isthmus cut too wide.
D- Flair of proximal walls too great.
E- Angle formed by the axial, buccal and lingual walls too great.
F- Gingival contact with adjacent tooth not broken.
G- Axial wall not conforming to the proximal contour of the tooth and the mesial-
distal width of the gingival floor is too great
indications for a stainless steel crown
- large lesions
- rampant caries
- following pulp therapy
- teeth with developmental defects
- fractured teeth
- temporary restoration of young permanent teeth
materials/instruments needed for doing a SSC
- Crown
- Contouring pliers
- Crimping pliers
- crown scissors
- heatless stone
- rubber wheel
3M ion crowns
-Pre-trimmed, belled and crimped to save placement time.
-Requires minimal adjustment for fast and easy placement.
-Accurately duplicates anatomy for better fit and performance
Unitek
May be needed when significant space loss has occurred secondary to interproximal decay
When caries extends further gingivally than the length of the Ion Crown
differences ION/EPSE SSC vs unitek SSC
-Unitek have flat axial surfaces and require axial contouring.
Unitek require crown shortening and marginal adaptation.
ION/ESPE have curved axial design (pre-contoured).
ION/ESPE have anatomically defined occlusal surfaces.
ION/ESPE require less manipulation to accurately fit a prepared tooth.
steps for fitting SSC
-Pick size
Length of crown
Marginal Adaptation Contouring
Crimping (snap fit)
location of finished crown margin
1 mm below gingival crest
when to use crown or normal restoration
If tooth to be lost within 3 years crown and alloy not significantly different.
Crowns significantly better if child under 5 years of age.
MECHANISM OF FORMOCRESOL ACTION
-Bactericidal effect
n Devitalizing effect
n Converts bacteria and pulp into inert compounds
n Inactivates the oxidative enzymes in the pulp
n Renders pulp inert and resistant to enzymatic breakdown
FERRIC SULFATE TECHNIQUE
-Control bleeding
n Place ferric sulfate using syringe with cotton tip or apply with cotton pellet for 15 seconds
-Rinse with water and dry gently with cotton pellet
n Cover pulp stumps with zinc-oxide-eugenol (IRM) or Glass Ionomer Cement/restore
crowns for primary incisors
strip crowns
