ANTERIOR FULL COVERAGE CROWNS

Question 1

indications for anterior full coverage crowns

Answer 1

aesthetics
broken down anterior teeth
TSL
trauma
atypical shape and hypoplastic conditions
milled crowns and attatchments for RPDs
retainers for cantilever bride work 
to alter occlusion

Question 2

contraindicators for anterior full coverage crowns

Answer 2

other more conservitive options viable
poor OH
uncontrolled caries
unstable and active perio disease
structurally compromised to the point of makeing crow retention a challenge
can lead to loss of pulp vitality
ceraminc can cause TSL in opposite dentition

Question 3

types of anterior crowns

Answer 3

metal ceramic or PFM
high strength ceramic
dentine bonded porcelain
acrylic 
resin based composite

Question 4

metal ceramic /PFM

Answer 4

metal core and ceramic veneer
deep labial reduciton 1.2- 1.5mm
shallow palatal prep 0.7mm
can have an exposed metal surface
- compromised aesthetics due to metal substructure

Question 5

dentine bonded porcelain crowns

Answer 5

thin layer of glass ceramics relying on bonding to underlying tooth structure for strenght
need to be able to etch material under crowwn

1. 5 incisal
2. 7-1 chamfer all round

Question 6

dentine bonded crown measurements

Answer 6

chamfer 0.7mm
incisal 1,5mm
5-10 degree tapered walls
buccal 2 plane reducton

Question 7

all ceramic crown (pressed)

Answer 7

strong core or full contour crown is produce by pressing ceramic material on a high temp on die
- crown is designed in wax

Question 8

all ceramic crown (glass infiltrated ceramic core sytem)

Answer 8

alumina core formed during slip casing
core porous and infiltrated with glass
dense core then prodcued

Question 9

1vs 2 layer crowns

Answer 9

2 layer
- metalcore /high strength ceramic core

1 layer
- if strength paramount
eg zirconia
or thin delicate crown bonded to underlying dentine, becomes strong due to the bond

Question 10

all ceramic crowns

Answer 10

1.2mm rounded chamfer
2mm incisal
more aesthetic due to no metal substructure

Question 11

indication for dentine bonded porcelain crown

Answer 11

minimally restored tooth
aesthetic paramount
absence of sig occlusal interferences or excessive loads

Question 12

high strength ceramic indications

Answer 12

structurally compromised tooth (missing/damaged structure)
aesthetics important
greater occlusal loading

Question 13

PFM indications

Answer 13

structurally compromised tooth (missing/damaged structure)
greater occlusal loading
combine with RPDs
exposed palatal metal surface with a lower coefficient of friction