Occlusion in Relation RPD

Question 1

Why are RPDs challenging to provide?

Answer 1

Pt has natural teeth which influence occlusion, position of teeth and occlusal plane
No., condition, location of remaining teeth has significant impact on denture construction

Question 2

What is ICP?

Answer 2

Intercuspation - the point of maximum causation between the teeth

Question 3

What is CR?

Answer 3

The relationship between mandible and maxilla when condyles seated in midmost uppermost position of glenoid fossa

Question 4

What is RCP?

Answer 4

First tooth contact when the codyles fully seated in glenoid fossa (roll tongue back)

Question 5

What is OVD?

Answer 5

Vertical dimension

Indicate superior inferior relationship of maxilla and mandible when teeth are in ICP

Question 6

Why is CR helpful?

Answer 6

Jaw relationship -not to do with teeth
Optimum position for neuromuscular system - tolerated well by pt
Reproducible position

Question 7

When may vertical dimension not be acceptable?

Answer 7

Not be stable - no remaining tooth contacts (remaining teeth don’t oppose)
Tooth wear case - significant loss tooth height
If over-eruption due to tooth loss

Question 8

How can unacceptable VD affect provision RPD?

Answer 8

Tooth wear case = need to restore teeth to natural height to fit connectors/ denture

Overeruption = may need to increase VD

Question 9

What are the 6 steps for producing RPD?

Answer 9

1. Primary imp - surgery and design denture
2. Tooth prep and secondary imp
3. Registration
4. Try-in
5. Fit
6. Review

Question 10

What is important to do when designing denture?

Answer 10

Survey the cast
Also need to check how teeth occlude so denture doesn’t interfere - articulate (can take silicone bite reg to help)
Can request registration rims and record occlusion if not obvious from cast

Question 11

What is involved in tooth prep and secondary imps?

Answer 11

If rest seats are required - cut to required dimension - enough space for rest w/o affecting occlusion
Ensure tooth prep picked up well by impression

Question 12

How to try in a Co-Cr framework?

Answer 12

Check framework fits well on cast and fully seats
Transfer into mouth - ensure seats well
Check occlusion
If needed alter

Question 13

How to carry out the registration phase?

Answer 13

Will be on wax/ shellac or acrylic base or metal framework for CoCr
Confirm occlusal relationship, tooth position and incisal plane
Adjust any discrepancies

Question 14

When are metal backings used?

Answer 14

When providing CoCr denture - good if strong bite/ deep overbite (if risk acrylic framework will fracture)
Increases no of appt

Question 15

What to do if stable ICP and acceptable VD?

Answer 15

Procede w/ mucosa borne denture

Tooth borne denture - consider position of occlusal rest (consider articulating model prior to design)

Question 16

What to do if no stable ICP but acceptable VD?

Answer 16

Establish new ICP to coincide w/ CR

Establish new occlusal scheme on registration rims and articulate model prior to design

Question 17

What to do if stable ICP but unacceptable VD?

Answer 17

Use registration rims to establish new ICP at correct VD - to be coincident w/ CR

Question 18

What to do if no stable ICP or VD?

Answer 18

Registration rims to establish new ICP at correct VD that coincides w/ CR