Outcomes of indirect restorations

Question 1

By how much do all ceramic anterior crown preps reduce tooth structure?

Answer 1

72%

Question 2

By how much do metal anterior ceramic anterior crown preps reduce tooth structure?

Answer 2

63%

Question 3

By how much do posterior metal crown preps reduce tooth structure?

Answer 3

68%

Question 4

By how much do posterior MCC crown preps reduce the tooth structure?

Answer 4

76%

Question 5

What proportion of crowned teeth subsequently undergo RCT?

Answer 5

4-8% at 8-10 years

Question 6

Generally, what is the 5 year survival rate for crowns?

Answer 6

92-97%

Question 7

What complications can occur with crowns?

Answer 7

Fracture (particularly in feldspathic porcelain), loss of retention, loss of abutment vitality, abutment fracture, caries

Question 8

Which teeth have higher failure rates, molars or premolars?

Answer 8

Molars

Question 9

Do upper or lower molars have statistically higher failure rates?

Answer 9

Upper

Question 10

Which is better, metal ceramic crown or zirconia?

Answer 10

No statistical difference