Framework Try-In

Question 1

Prepared master casts are duplicated to produce…

Answer 1

an exact copy of master cast in investment material (refractory cast)

Question 2

Framework pattern will be fabricated on the __________ cast using wax

Answer 2

refractory

Question 3

An impression Using _____________________ is made of the block out on the master cast to create the refractory cast

Answer 3

reversible hydrocolloid (Agar)

Question 4

TIPS FOR THE FRAMEWORK TRY IN:

Answer 4

▪The completed RPD must be passive.
▪Should not exert forces on the teeth or soft tissues.
▪The tip of each retentive clasp should lie passively in a measured undercut.

Question 5

Block Out and Relief Wax is Placed on the __________ CAST

Answer 5

MASTER

Question 6

Master cast with block out and relief wax is duplicated twice and each is used for…

Answer 6

One is Poured in Stone and one in High Heat Refractory Material

Question 7

The wax-up of the RPD framework is completed on the __________ cast.

Answer 7

refractory

Question 8

The refractory cast is usually _______, and the material is ________________.

Answer 8

white
high heat investment

Question 9

The wax-up of the RPD framework is completed on the ____________ cast

Answer 9

refractory

Question 10

Laboratory returns the framework on the ____________ cast

Answer 10

duplicate or “fitting” cast

Question 11

Difference between master cast and duplicate cast

Answer 11

Question 12

The dentist should be the first to evaluate the fit on the master cast including:

Answer 12

▪ Path of placement
▪ Action of retentive & reciprocating arms
▪ Areas of interference/Scraping of cast
▪ Accuracy of seating

Question 13

Dentist should evaluate the framework on the __________ cast

Answer 13

master

Question 14

Evaluate ____________ surfaces for proper finish and construction

Answer 14

external/internal

Question 15

What do you need to check the fitting, occlusion, and intraoral fit of framework?

Answer 15

▪Good light
▪Magnification
▪Mirror and explorer

Question 16

How should the framework fit to the teeth?

Answer 16

▪Position direct retainers over the abutments
▪Place fingers over rests and push along the path of placement
▪The framework should move smoothly with minimal resistance
▪Balanced resistance should exist

Question 17

What happens if there is not balanced resistance?

Answer 17

▪ A more rigid retentive tip on one abutment than another will cause tilting
▪ If the framework is not fully seated, the retainers will not be passive and will exert forces against the teeth

Question 18

What should you evaluate on the external surface of RPD?

Answer 18

▪ Rests
▪ Major Connector
▪ Minor Connectors
▪Direct Retainers
▪Indirect Retainer
▪External Finish Lines

Question 19

What should the finish of the intaglio surface look like?

Answer 19

▪ Surface should be smooth and free from irregularities (no bubbles, blebs, and artifacts)
▪ Surface is not highly polished

Question 20

What are the possible causes for framework misfit?

Answer 20

▪ Faulty impression technique
▪ Faulty casts
▪ Tooth movement
▪ Casting inaccuracy

Question 21

What are ways that the impression could be faulty?

Answer 21

▪ Lack of uniform thickness of impression material
▪ Intraoral distortion due to tray movement
▪ Extraoral distortion due to faulty handling

Question 22

What are ways that the casts could be faulty?

Answer 22

▪ Improper water to powder ratio
▪ Improper spatulation
▪ Failure to use double pour cast formation technique when making impressions in irreversible hydrocolloid

Question 23

What issues can you have with tooth movement from impression to framework try-in?

Answer 23

▪ Tooth movement due to occlusal disharmonies/ periodontally involved teeth
✓Mesially inclined mandibular molars
✓ Lone standing premolars
▪ Recent extractions

Question 24

What are the teeth that are likely to have movement from impression to framework try-in?

Answer 24

✓Mesially inclined mandibular molars
✓ Lone standing premolars

Question 25

What can cause casting inaccuracy?

Answer 25

▪ Expansion of the investment
▪ Shrinkage of Ni-Chrome alloys is 2.2 to 2.4% during casting

Question 26

How do you fit the RPD frameowrk intraorally?

Answer 26

▪Adjust the framework
▪Adjust the direct retainers
▪Adjust the occlusion

Question 27

What are common ares of framework interference?

Answer 27

▪ Internal surfaces of direct retainer shoulders
▪ Internal surfaces of direct retainer bodies
▪ Internal surfaces of minor connectors
▪ Interdental papilla areas

other areas that cause interference
▪ Reciprocating arms
▪ Lingual plating
▪ Soft tissue

Question 28

Shrinkage of Ni-Chrome alloys is _______% during casting

Answer 28

2.2 - 2.4

Question 29

What are the disclosing materials that can be used to identify interferences?

Answer 29

• NEY Spray
• Occlude
• Kerr Disclosing Wax

Question 30

How do you use disclosing materials to located interferences?

Answer 30

▪Dry the framework
▪Place a thin layer of indicating material
▪ Insert framework along path of insertion
▪ Apply finger pressure
▪ Remove the framework and note areas of interference
▪ Adjust area of interference with a small bur or stone
▪ Wipe framework clean and repeat procedure until the framework is seated

Question 31

The framework should seat without a _____

Answer 31

click

Question 32

What are other ways to locate interferences in addition to disclosing material?

Answer 32

▪Evaluate contact of direct retainers and reciprocating arms
▪Check for wedging - modification spaces
▪Adjust the occlusion

Question 33

Assure that the _______ relationship exists in centric relation (occlusion) and eccentric functional movement with the framework in the mouth, as exists between the teeth when the framework is not present.

Answer 33

same

Question 34

Adjust the occlusion on the RPD framework for _____________

Answer 34

centric relation

Question 35

What should you check when adjusting for centric relation?

Answer 35

✓Maintain bulk of rests for strength
✓Opposing teeth may need modification