question 14

Question 1

what do you do first for critiquing casts

Answer 1

Assess casts mounted on articulator using articulating paper, 8 micron shimstock and calipers and decide whether you would cement crown and reduce to gain balanced occlusion or you would make decision to redo the prep and send back to the lab. List any faults with crown prep

Question 2

what are pre cementation checks

Answer 2

o Does the restoration match the prescription?
o Check fit on the cast
▪ Rocking, contact points, margins, aesthetics
▪ Check casts for damage, especially at contact points
▪ Occlusal interference on excursive movements
▪ Check for natural tooth contact with shimstock 8μm
▪ Check prep for adequate reduction
o Remove crown from cast and check
▪ If natural teeth contact now
▪ Check if tooth is under prepped
▪ Measure crown thickness using calipers

● Minimum 0.5mm thickness circumferential
● Minimum 1.5mm for functional cusps and 1mm for non-
functional

Question 3

what to do in future

Answer 3

Avoiding fault in future
o Measure temp crown thickness before cementing
o Use sectioned putty index when preparing

Question 4

management crown

Answer 4

Management
o Check mount of interference by dropping incisal pin and calculate the difference – if able to reduce crown without making it too thin, adjust it then cement it
o Otherwise – redo prep and send back to the lab for a new crown