Taking secondary impressions

Question 1

What are these?

Answer 1

tissue blocks in edentulous saddle areas

Question 2

What is the purpose of these?

Answer 2

stabilise the tray in the mouth at the correct height for correct spacing

Question 3

Why do you cut the peripheries of the impression tray back by 2mm?

Answer 3

allow full sulcus extension

Question 4

What has been added to the periphery of the secondary impression tray?

Answer 4

silicon putty for border moulding

Question 5

What do you fill the tray with to get the impression?

Answer 5

silicon putty - gives superior detail

compared to alginate

Question 6

Why is silicon putty used for secondary impressions and not alginate?

Answer 6

superior detail and the nature of the rest seat preparations

Question 7

What details do you want from this impression?

Answer 7

sulcus

retromolar areas

no undercuts to hinder easy insertion and removal of the tray during the next step

Question 8

Now we have completed the peripheral border impression with silicon, what are the steps to get the secondary impression?

Answer 8

1. dry teeth thoroughly (3in1)
2. light bodies silicon is applied
3. dental nurse loads the custom tray with medium viscosity silicon
4. put impression in mouth, press down firmly on areas with impression stops
5. ensure lower lip is free and move tongue in various directions

final product shown

Question 9

What is the purpose of applying light bodies silicon before taking impression?

Answer 9

capture fine detail of tooth preparations

Question 10

Describe the silicon used to take the secondary impression?

Answer 10

dental nurse loads the custom tray with medium viscosity silicon

Question 11

What is this showing?

Answer 11

apply light bodies silicon to hard areas, pay particular attention to prepared areas of the teeth

Question 12

Example of disinfection?

Answer 12

unoguard

Question 13

How long to leave impression in disinfection?

Answer 13

10 mins