Decalcification

Question 1

Most common & fastest decalcifying agent used for routine
But it imparts yellow color

Answer 1

Nitric acid

Question 2

How to prevent yellow stain in nitric acid

Answer 2

1. Neutralization using 5% sodium sulfate & wash in running H2O for 12 hrs
2. Addition of 0.1% urea to pure nitric acid

Question 3

Decalcifying agent + Tissue softener

Answer 3

Perenyi’s

Question 4

Most rapid decalcifying agent (12-24hrs)

Answer 4

Phloroglucin-Nitric acid

Question 5

Recommended for surface decalcification of the tissue blocks

Answer 5

Hydrochloric acid

Question 6

Contains sat. aq soln of NaCl, 36% concentrated HCl & distilled h2o

Answer 6

Von Ebner’s

Question 7

Very wear decalcifying agent for minute pieces of bone

Answer 7

Sulfurous acid

Question 8

For bone spicules

Answer 8

chromic acid

Question 9

Anticoagulant & water softener

Answer 9

EDTA

Question 10

uses ammonium form of polystyrene resin but not recommended for fluids

Answer 10

Ion-exchange resins (20-30x the vol of tissue)

Question 11

Decalcification is shortened in this method but its satisfactory for small bon fragments

Answer 11

electrophoresis

Question 12

Faster than routine decalcification

Answer 12

Microwave oven decalcification

Question 13

Measuring the extent of decalcification:
most sensitive, ideal & reliable

Answer 13

Xray/radiological

Question 14

Measuring the extent of decalcification:
touching or bending or needling
vague & inaccurate

Answer 14

physical/mechanical

Question 15

Measuring the extent of decalcification:
simple, reliable, convenient & routine

Answer 15

Chemical/calcium oxalate test
(performed on discarded fluid)

Question 16

examples of tissue softeners

Answer 16

• Perenyi’s
• 4% a1. phenol soln
• Molliflex
• 2# HCl or 1% HCl in 70% Alcohol