A. Custom trays facilitate uniform contraction of impression material
B. Custom trays require less impression material
C. Stock trays may be short in the flange area
D. Impressions made n the custom trays are easier to remove from the mouth
Related Mcqs:
- The cross linking agent of polysulphide rubber base impression material is______________?
A. Aromatic sulfonate esters
B. Stannous octate
C. Platinum salt catalyst
D. Lead dioxide - Best impression material to be used for securing impression after crown preparation_______________?
A. Alginate
B. Agar
C. Elastome
D. Zno paste - All of the following statements about Type II silicon impression material are true EXCEPT_______________?
A. They evolve hydrogen when cast if they are not fully cured
B. They exhibit a very low setting shrinkage
C. They have a lower tear resistance than polysulphide rubbers
D. They set by condensation polymerisation - Impression compound is characterized by all of the following except_______________?
A. Warps at room temperature
B. Is a thermoset material
C. Shows increased flow when kneaded with water
D. Low coefficient of thermal conductivity - 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 - 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 - Palatal secretions affect the setting of all the impression materials except_______________?
A. Silicone
B. Agar-agar
C. Impression paste
D. Impression plaster - 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 - The anatomic crown is shorter than the clinical crown of a tooth in which of the following instances___________________?
A. Impaction
B. Gingivitis
C. Occlusal wear
D. Gingival recession - Impression compound has which of the following characteristic property ?
A. Low thermal conductivity
B. High flow property
C. Degradation is presence of moisture
D. Remain distortion free up to 72 hrs. pouring can be safely delayed
