Lecture 4-Class III and IV Design

Question 1

In a Class III situaiton denture bases, therefore, generally do not ______ or _____ away from the underlying tissues

Answer 1

ROTATE or LIFT

Question 2

In a Class III situaiton compensation for ________ forces is not needed.

Answer 2

ROTATIONAL

Question 3

The Class III can frequently be used as a valuable aid to ________ treatment because of its stabilizing influence on the remaining teeth

Answer 3

periodontal

Question 4

In a Class III, denture base of Class III may be WHAT MATERIAL? since relining is not an ongoing concern…

Answer 4

metal

Question 5

Is indirect retention necessary in a Class III?

Answer 5

NO!

Question 6

Why is indirect retention NOT NECESSARY in a Class III?

Answer 6

there is no FULCRUM line!

Question 7

In the Class IV arch the ______ line passes through the two abutments adjacent to the single edentulous space.

Answer 7

fulcrum

Question 8

Forces acting to move the denture base away from the edentulous ridge in a Class IV RPD must be resisted by WHAT? positioned posterior to the fulcrum line.

Answer 8

indirect retainers

Question 9

Forces acting to move the denture base IN WHICH DIRECTION? the edentulous ridge in a Class IV RPD must be resisted by indirect retainers positioned posterior to the fulcrum line.

Answer 9

AWAY FROM

Question 10

Forces acting to move the denture base away from the edentulous ridge in a Class IV RPD must be resisted by indirect retainers positioned ________ to the fulcrum line.

Answer 10

POSTERIOR

Question 11

WHAT TYPE of RESTS _________ provide effective indirect retention for CLASS IV framework.

Answer 11

Embrasure rests

Question 12

Class IV is often a good indication for which retentive feature?

Answer 12

Rotational Path

Question 13

Which feature is this describing?: Incorporates a curved or variable path of placement allowing one or more of the rigid components of the framework to gain access to and engage an undercut

Answer 13

Rotational Path

Question 14

How do you usually classify a rotational path RPD?

Answer 14

Anterior to Posterior OR Posterior to Anterior

Question 15

Generally, it is better treatment to replace missing teeth with a ______ restoration

Answer 15

FIXED

Question 16

A notable exception for RPD over FPD is when ______ teeth are lost along with significant amounts of ________.

Answer 16

anterior…alveolar bone

Question 17

What can you avoid when doing a Class IV RPD instead of an FPD?

Answer 17

long span pontics!

Question 18

When feasible, close modification spaces with _____’s, ESPECIALLY free-standing _______ and _______ teeth.

Answer 18

FPD’s….premolars and anterior

Question 19

Replacing free standing PM’s with FPD BECAUSE: free standing premolars cannot resist ______ forces

Answer 19

torquing

Question 20

Replace anterior teeth with FPD’s because they tend to ROCK _______ and _______ when the distal extension is depressed.

Answer 20

superior and inferiorly

Question 21

Extensive alveolar bone loss necessitating tooth replacement AND Alveolar Bone. is a good indication for a _______ RPD

Answer 21

Class IV

Question 22

What are the two main goals when preparing an embrasure clasp?

Answer 22

1. Dont open the contacts! 2.Lower the MR 1.5mm!

Question 23

In Class I and II, what is the PRIMARY support for the RPD?

Answer 23

the underlying tissues!

Question 24

In Class I and II, what is the SECONDARY support for the RPD?

Answer 24

the abutment teeth! (underlying tissues are primary!)