LESSON 6: INFILTRATION AND EMBEDDING

Question 1

to fill all natural cavities, spaces & interstices of the tissues

Answer 1

IMPREGNATION

Question 2

to give tissue samples a firm consistency

Answer 2

IMPREGNATION

Question 3

impregnated tissue is placed into a precisely arranged position in a mold containing a medium which is then allowed to solidify

Answer 3

EMBEDDING

Question 4

➢ substance used to infiltrate, support and enclose tissue specimen
➢ should be the same for infiltration and embedding
➢ most important characteristic: convertible from liquid to solid form

Answer 4

Infiltration/Embedding media

Question 5

WHAT ARE THE MECHANISMS OF INFILTRATION/EMBEDDING MEDIA?

Answer 5

→crystallization
→evaporation of the solvent
→polymerization

Question 6

Simplest, most common & best embedding medium

Answer 6

PARAFFIN PROCESSING

Question 7

What are the considerations under infiltration/embedding?

Answer 7

1. Laboratory Temperature
2. Hardness of the Tissue sample
3. Temperature during Infiltration
4. Number of changes
5. Nature and Size of the Tissue sample
6. Clearing Agent Used

Question 8

What should be the laboratory temp?

Answer 8

✓ 20-24 OC (Room Temp): 54 – 58C
✓ 15-18 OC: 50-54C

Question 9

What should be the temperature during infiltration using a paraffin oven?

Answer 9

2 – 5C higher than the MP of the wax

Question 10

What will happen if the temperature during infiltration is beyond 60 degreed Celsius?

Answer 10

It would be deleterious to the tissue

Question 11

What is the minimum requirement for changing infiltration/embedding media?

Answer 11

At least 2 changes

Question 12

What are the methods of paraffin embedding?

Answer 12

1. MANUAL PROCESSING
2. AUTOMATIC PROCESSING
3. VACUUM EMBEDDING

Question 13

❖ 4 changes at 15-minute intervals
❖ 2-5C higher than the MP of the wax

Answer 13

MANUAL PROCESSING

Question 14

❖ 2 – 3 changes with agitation
❖ At least 3C higher than the MP of the wax

Answer 14

AUTOMATIC PROCESSING

Question 15

❖ 3 changes
❖ 2 - 4C above MP of wax

Answer 15

VACUUM EMBEDDING

Question 16

Vacuum embedding uses?

Answer 16

Negative atmospheric pressure (400-500mmHg)

Question 17

Fresh was should be filtered at _____ above its MP

Answer 17

2C

Question 18

Wax from trimmings should be filtered with a ________________?

Answer 18

course filter paper

Question 19

Water is removed by heating the wax to _____________?

Answer 19

100-105C

Question 20

Paraffin should be melted at?

Answer 20

5-10C above the MP of wax

Question 21

What is the cooling of Paraffin embedding?

Answer 21

Ref at -5 Degrees Celsius

Question 22

What are the substitutes for Paraffin wax?

Answer 22

1. Paraplast
2. Ester wax
3. Water Soluble Waxes