Which of the following best describes the working time of elastomeric impression material ?

Related Mcqs:

1. The American dental association (ADA) specification number for non-aqueous elastomeric dental impression material is______________?

   A. 19
   B. 20
   C. 21
   D. 26

2. Dimensional stability of elastomeric impression material can be given in descending order as_____________?

   A. Polysulphide > polyether > Condensation silicone > Addition silicone
   B. polyether > Condensation silicone > Polysulphide > Addition silicone
   C. Addition silicone > polyether > Polysulphide > Condensation silicone
   D. Addition silicone> Condensation silicone > Polysulphide > polyether

3. What is the minimum thickness of the elastomeric impression material for an accurate impression_______________?

   A. 2 mm
   B. 2-4 mm
   C. Greater than 3 mm
   D. Maximum in the area of operation

4. Alginate impression material is similar to Agar-agar impression material in the following respect________________?

   A. Gelation increase in both on increase in temperature
   B. Mixing time is increased to reduce the setting time
   C. Deformation during removal of impression occurs due to distortion of gel fibers
   D. Both can be re-used for fresh impressions

5. Which of the following best describes the working time of impression material ?

   A. After the start of appearing elastic properties of impression material
   B. Just after the start of appearing elastic properties of impression material
   C. The time for start of mixing till just before the start of appearing elastic properties of impression material
   D. Loss of lusture of impression material

6. Which of the following is not true about elastomeric impression ?

   A. Single mix material have higher viscosity
   B. Shear thinning is related to viscosity of non phase impression material
   C. Improper mixing of material can cause permanent deformation of impression
   D. Putty – wash technique of impression reduces dimensional change of setting

7. Rough surface of elastomeric impression results from_______________?

   A. Inadequate mixing
   B. Air bubbles
   C. Too rapid polymerization
   D. Incomplete polymerization caused by premature removal from mouth

8. Best impression material to be used for securing impression after crown preparation_______________?

   A. Alginate
   B. Agar
   C. Elastome
   D. Zno paste

9. Which of the following impression materials is easy to pour and difficult to remove the stone cast from the impression ?

   A. Addition polysilicone
   B. Condensation polysilicone
   C. Polyether
   D. Polysulfide

10. Agar impression materials differ from alginate impression materials in that the former sets by_______________?

    A. Mechanical action of saliva
    B. Physical change
    C. Evolution
    D. Chemical change