Chapter 46 Recall Questions 1-23 Chapter 47 Critical Thinking 1-5
1 Is an impression a negative or a positive reproduction?
An impression is a negative reproduction.
2 Of the three classifications of impressions, which can the EFDA legally take?
The three classifications consist of preliminary impression, final impression and bite registrations. EFDA can legally take preliminary and bite registrations.
3 Which of the three classifications of impressions is used for occlusal relationships?
Bite registrations is used for occlusal relationships.
4 Which type of impression tray covers half the arch?
Quadrant trays can cover half the arch.
5 Which type of tray allows impression material to lock on mechanically?
Solid platic tray allows impression material to lock on mechanically.
6 Which type of impression tray is used most often for taking final impressions?
Custom tray is constructed to fit the mouth of a specific patient.
7 What is used to extend the length of a tray?
Utility wax is used to extend the length of a tray.
8 What is the organic substance within hydrocolloid materials?
Hydrocolloid is material used to obtain preliminary and final impressions.
9 Why would you select a fast-set alginate over a normal-set alginate?
Using fast-set alginate allows the tray to be removed from the patient’s mouth sooner, creating more comfort especially if patient has severe gag reflex.
10 What is the water-to powder ratio for taking a maxillary impression？
Three measures of water is mix with powder.
11 What does the prefix “hydro-”mean?
Hydro means water.
12 What is another name for irreversible hydrocolloid?
Alginate is another name for irreversible hydrocolloid.
13 Do you mix irreversible hydrocolloid on a paper pad or in a mixing bowl?
Irreversible hydrocolloid, alginate is mixing in a mixing bowl.
14 Before an impression is taken with reversible hydrocolloid, where is the material kept?
The material is kept in a conditioning bath.