MCQs on Impression Materials

Which of the following is a characteristic of an ideal impression material?

• High dimensional stability

• High viscosity

• Poor tear strength

• Long setting time

Which impression material is classified as an elastomeric material?

• Zinc oxide eugenol

• Polyvinyl siloxane

• Plaster of Paris

• Impression compound

Which of the following impression materials has the highest tear strength?

• Alginate

• Polysulfide

• Polyether

• Polyvinyl siloxane

Which component in alginate powder is responsible for controlling the setting time?

• Calcium sulfate

• Sodium alginate

• Sodium phosphate

• Diatomaceous earth

Which impression material is most hydrophobic?

• Polyether

• Polyvinyl siloxane

• Alginate

• Polysulfide

What is the purpose of adding retarders to impression materials?

• Increase tear strength

• Prolong working time

• Enhance dimensional stability

• Reduce viscosity

Which of the following is a rigid impression material?

• Alginate

• Polyether

• Zinc oxide eugenol

• Polyvinyl siloxane

During a complete denture case, a dentist notices that the alginate impression taken for the preliminary cast has distorted after 30 minutes. What is the most likely cause?

• Syneresis

• Excessive water in the mix

• Use of a stock tray

• High tear strength

A dental student is taking an impression using polyvinyl siloxane (PVS) for a bridge. The material fails to set properly. What could be the reason?

• Contamination with latex gloves

• Excessive moisture in the oral cavity

• Overmixing of the material

• Use of a perforated tray

While taking an impression with polyether, the dentist finds it difficult to remove the set material from the patient's mouth. What property of polyether is responsible for this?

• High viscosity

• High stiffness after setting

• Poor tear strength

• Hydrophobic nature