Ceramic onlay & Practical Review Flashcards
whats an onlay? how is it retained?
partial coverage restoration that restores one or more cusps, some or all of the occlusal surface and is retained by mechanical or ADHESIVE means
what materials used for onlays
these days often lithium disilicate!! (emax)
or zirconia
LD IS BETTER for some reason when it comes to occlusal onlays..
sequence / lifetime of a tooth from filling to an implant
filling -> bigger filling aka ONLAY -> root canal / crown/ BU - what is bu??? -> extraction -> implant
prep criteria for a onlay that we did
greater than 1.5 mm isthmis width
- no sharm internal angles
- 2 mm reduction on functional cusps
- 1.5 to 2 mm pulpal depth at central groove
- greater than 1 mm margin depth-
- greater than 90 degree exit angles
- at least .5 mm gingival/proximal clearance
- all internal walls have flare/diverge
placed buccal margin 2 mm below the cusp
-need greater than 1.5 mm clearance (1.5 to 2 mm clearance?)
whats the compression dome concept
MOD onlay is like a compression dome
for an onlay how should the internal walls be positioned?
DIVERGENT!!
why do we conserve enamel
looks, caries resistance vs dentin, strength, predictable bond!
bonding protocol for onlay
- ISOLATION; ISODRY or rubber dam
- FULL BONDING PROTOCOL
- TECHNIQUE SENSITIVE
bonding is super important for an onlay (esp with all cusps taken down) the ONLY retention is via adhesion- NO mechanical retention there
how do you bond a provisional to onlay
what type of cement do we use, how do you remove it?
spot bond
-place a small dot of etch on pulpal floor. rinse. place a small amount of bonding agent on the same area, then bond temp with flowable
durelon: carboxylate cement; permanent cement that is easily removed with ultrasonic
kinda confused on waht they want us to do, exactly..?
