EXTRA COR REST - MCC Crowns - Metal Ceramic Crowns Flashcards
1
Q
3 advantages.
A
aesthetic
strong
durable
2
Q
2 disadvantages
A
- the porcelain layer needs to be thick to hide the metal underneath
therefore = greater amount of tooth prep needed - metal appearance
3
Q
where would MCC be used?
A
same as gold crown
- posterior teeth
- where aesthetics may not be important
realistically
prob anterior
4
Q
how can MCC vary?
A
the ceramic can wrap around the front, front and occlusion or all the way around
- the more ceramic used = the more prep required
5
Q
describe the manufacturing process
A
- prepare the tooth
- take an impression
- wax pattern made
- sprued
- metal model is tried on the model
- trimmed to fit the die
- porcelain build up
6
Q
what does it mean to be sprued?
A
a channel in which molten metal is poured into the mould
7
Q
what is the die?
A
the reproduction of the form of a prepared tooth on the cast model
8
Q
how do you build up the porcelain?
A
- lay down opaque porcelain
- lay down layers of dentine and enamel shaded porcelain
9
Q
how do you prepare a MCC? reductions and burs
A
occlusal - 2mm
labial - 1.2-1.5mm - shoulder
palatal - 0.5mm - chamfer
