Lab Stages_Final Denture Processing/Fabrication

Question 1

What is the purpose of flasking/investing and when is it done?

Answer 1

• Creates moulds to use for fabrication of acrylic denture base
• Done after wax denture comes back

Question 2

What is the purpose of boiling and packing and when is it done?

Answer 2

Constructs final denture base

Done after flasking

Question 3

What is the purpose of deflasking and when is it done?

Answer 3

Removes the final denture from the flask containers and separates it from the plaster
Done after boiling and packing complete and acrylic set

Question 4

What is the purpose of trimming and when is it done?

Answer 4

Removes excess acrylic created from the boiling and packing process
Done after deflasking

Question 5

What are the lab steps?

Answer 5

Part I (flasking/investing/mould creation)

1. Place wax denture on model
2. Acquire a falsking container
3. Fill one part of container with plaster (call this part of container the lid)
4. Place model (back first) into plaster inside lid and place wax denture onto model + remove excess plaster
5. Fill container body with plaster. Coat some of the plaster onto the wax model
6. Place the body onto the lid and wait for plaster to set.

Part II (Boiling and Packing/acrylic base creation)
1. Separate the lid and the body
Result at this stage should be:
-Lid: Plaster set with master cast attached
-Container: Plaster set with wax denture attached (teeth down)
2.. Remove the wax from the plaster cast, separating it from the teeth
Final result
-Lid: Plaster set with master cast attached
-Container: Plaster set with teeth only embedded in plaster, preserved in the same position as in wax denture. Mould also records the original shape of the wax base after it is removed
3. Mix up some acrylic dough
4. Place/adapt into the container body (one with the teeth (Mould of wax base will cause acrylic to mimic its shape, and teeth are positioned exactly as they were in the wax denture)
5. Place the lid back on the container (the master cast attached to the lid will cause the back of the acrylic to adapt to the shape of the patient’s arches, thus creating the final shape of denture)
6. Pressure is placed on the container to allow the acrylic to set

Part III (deflasking and trimming)

7. The final denture is then deflasked (removed from the container and separated from the plaster)–>destruction of the master cast may be inevitable in this process
8. Excess acrylic is trimmed

(Refer to google docs for images)