Class 1 composite restoration- caries removal Flashcards
when composites were first a thing, how were they cured?
chemically and were used for class 3,4,5
whats has changed with modern composites vs older composites?
Filler size has reduced, and filler amounts have increased up to 70%
whats a nano-hybrid composite?
the smaller filler particles ( nano particles) are intermixed with larger glass and silica particles giving the material toughness.
what composite system do we use at LECOM?
BEAUTIFIL Nanohybrid
do The prep walls have to be convergent?
no they can be parallel to divergent
the prep pulpal depth should be __ past the DEJ?
.5 mm
Advantages of Composite?
Esthetics, conserve more tooth structure, easier preparation, insulation
Disadvantages of composite
Shrinkage, Lower fracture toughness, possible greater localized occlusal wear
on average the composite shrinks how much?
2.6-7.1 %
Do you want centric stops to be on composite or amalgam?
no, They need to be on natural teeth.
how wide should the isthmus be?
1.5mm, also dont encroach past 1/3 of the cusp tip of the cusp
Retention is achieved by micromechanical means which means…..
- etching of enamel and Dentin
- proper bonding technique
- placing bevels
Does the beutibond bond to the tooth?
no , the adhesive
What bur is best to use for entry?
330 or 245
how far pulpal should you go down?
~1.5 mm initially, then you can go 2mm. as you continue to drill
what bur can you use to smoothen the walls?
use a low speed 56 carbide bur
what should the marginal thickness be?
Premolars is 1.5mm, molars, 2 mm.
why dont we bevel the occlusal surface?
it creates a very thin and weak composite area that is prone to chipping and increases recurrent caries risk.
where can you bevel?
facial or ligual of a tooth ( since its not under stress its ok)
why do caries spread at the DEJ?
a lot of tubules
what MUST be achieved before caries removal pulpally begins?
a stain free DEJ
how do we distuingish between healthy and infected dentin?
degree of discoloration and hardness.
who developed the caries indicator? Why is it not good?
Fusyama, its not specific for infected dentin and stains slightly demineralized protein matrix of affected dentin as well.
Caries removal process
use spoon excavator, start with the largest spoon and move to smaller sizes if needed, Remember the stain free DEJ
