Impression Techniques In Fixed Partial Denture

Impression Techniques In Fixed Partial Denture

Question 1. Difference between  Addition Silicone And Condensation Silicone 
Answer:

The difference in Setting Reaction of Addition and Condensation Silicone:

Question 2. Write a short note on the wet field technique.
Answer:

The wet field technique is the alternative technique of applying syringe material of reversible hydrocolloid material, i.e. agar

• In this technique area that has to be recorded is bathed in warm water and syringe material is deposited only on the occlusal or incisal surface of teeth.
• Tray material gets seated.
• The hydraulic pressure of viscous tray material forces the fluid syringe hydrocolloid down in the areas which are to be recorded.
• This motion displaces the syringe material, blood, and debris throughout the sulcus.
• The impression should be removed with the sudden snapping motion.

Question 3. Write a short note on the silicone rubber base impression material.
Answer:

There are two types of silicone rubber base impression material present based on the type of polymerization reaction occurring during its setting.

The materials are:

• Condensation silicones
• Addition silicones

Question 4. Write the Classification of zinc oxide eugenol impression pastes.
Answer:

A dental impression is defined as a negative record of the tissues of the mouth.

Classification of Zinc Oxide Eugenol Impression Paste:

ADA specification No. 16

• Type I or hard
• Type II or soft.