Chapter 14

Question 1

A lower bar overdenture requires a minimum of how much vertical space from the implant platform to the incisal edges?

a. 6mm
b. 8mm
c. 10mm
d. 12mm

Answer 1

d. 12mm

Question 2

The B and D sites in the mandibular symphysis are closest to the site of :

a. The natural lateral incisors
b. Between the laterals and cuspids
c. The natural cuspids
d. Between the cuspids and first bicupsids
e. The natural first bicuspids

Answer 2

b. Between the laterals and cuspids

Question 3

An overdenture with two ball attachments will typically have prosthesis movement in

a. One direction
b. Two directions
c. Three directions
d. Six directions

Answer 3

d. Six directions

Question 4

Which is most likely to cause the fracture of the distal extension of an overdenture bar?

a. Screw loosening
b. Hidden cantilever effect
c. Metal rider clips
d. Use of porcelain denture teeth

Answer 4

b. Hidden cantilever effect

Question 5

Which factor will not cause you to consider reduced cantilever length?

a. Heavy bite force
b. Increased crown-implant ratio
c. Older female pt
d. history of parafunction

Answer 5

c. Older female pt

Question 6

Two implant overdentures should use B-D sites rather than A-E because:

a. Rotation and depression to the posterior is more desirable and well tolerated
b. A more distal bar is nearer the molars where bite forces are highest
c. Bone in the more posterior sites is more resistant to resorption
d. Carl Misch said so, so it must be true

Answer 6

a. Rotation and depression to the posterior is more desirable and well tolerated

Question 7

An OD-2 moves in such a way that the attachment works like a

a. Magnet
b. Spring
c. Hinge
d. Wheel or pulley

Answer 7

c. Hinge

Question 8

Which is not an advantage of an OD-1 compared to a conventional CLD?

a. Reduces soft tissue abrasions
b. Reduced maintenance
c. Improved speech
d. Improved bite force

Answer 8

b. Reduced maintenance

Question 9

Which of the following is not true?

a. It is acceptable to cement bar overdentures.
b. More demanding patients dictate more complex overdenture designs
c. Fixed restorations can be done in less space than bar overdentures
d. A two implant overdenture is a definitive tx that cannot be improved upon

Answer 9

d. A two implant overdenture is a definitive tx that cannot be improved upon

Question 10

An OD-4 or 5 with multiple Hader bar segments at different angles has

a. Hinge movement
b. 6 directions of movement (PM6)
c. low pt satisfaction
d. little to no prosthesis movement.

Answer 10

c. low pt satisfaction