Decalcification Flashcards
Factors that affect decalcification time: (4)
- Degree of mineralization
- Volume of decalcifying agent
- Temperature
- Application of heat/agitation
Ratio of agent to tissue volume
20:1
Temperature when decalcifying specimen
18-20°C
Method to measure the extent of decalcification: (4)
- Mechanical/Physical
- Radiological/Xray
- Bubble test
- Chemical/Calcium oxalate
Method of testing for the completeness of decalcification done by probing tissue with a needle
Mechanical/Physical
Most reliable method of testing for the completeness of decalcification
Radiological/Xray
This method of testing uses calcium carbonate
Bubble test
Presence of this indicates incomplete decalcification
Presence of bubbles
Methods of decalcification: (4)
- Use of chelating agent
- Electrolytic method
- Use of acid
- Ion Exchange Resin
Potent anticoagulant but weak decalcifying agent
EDTA
Binds with calcium to form weakly dissociated complexes
EDTA
An excellent bone decalcifier for EM and enzyme histochemistry
EDTA
Disadvantage of EDTA
Inactivates alkaline phosphatase
Most rapid decalcification method that involves attraction if positively charged calcium ions with negatively charged electrodes
Electrolytic method
Use of hydrochloric acid
Surface decalcification of blocks
Use of Perenyi’s fluid
Decalcifying agent and tissue softener
Most commonly used decalcifying agent
5-10% Nitric Acid
Use of 5-10% Nitric Acid
Recommended for urgent biopsies, needle and small biopsies
Most rapid nitric containing decalcifying agent
Fluoroglucin Nitric
Duration of Ion Exchange Resin
14 days or longer
Tissue softener’s that is utilized if the tissue is still hard after decalcification
Molliflex - Perenyi’s
