Tissue Decalcification for Paraffin Processing

(based on 128 customer ratings)

Author: Diana Harrington, BS, HT(ASCP)
Reviewer: Carla Shoffeitt, MSM, HT(ASCP)

This course aims to simplify the decalcification process and provide useful techniques to work with calcified tissue successfully.

Continuing Education Credits


  • Define the bone types and their composition.
  • Describe techniques used to remove mineral from bone or other calcified tissue.
  • Determine the end-point of decalcification based on the method used.
  • Identify troubleshooting strategies used when unexpected calcium is revealed or if tissue is under- or over-decalcified.

Course Outline

  • Overview
      • Tissue Decalcification for Paraffin Processing
  • Bone
      • Bone Types
      • Bone Composition
      • Bone Cells
      • Bone is primarily comprised of what mineral?
  • Fixation of Calcified Tissue
      • Fixation of Calcified Tissue
      • Fixation of Calcified Tissue, continued
      • Incomplete fixation of specimens prior to decalcification will affect staining quality.
  • Methods Used to Decalcify Tissue
      • Decalcification Methods Using Acids
      • Strong Mineral Acids
      • Weak Organic Acids
      • Chelation With EDTA
      • Electrolytic Methods
      • Match the following decalcification acids with the correct classification as either a strong mineral acid or weak organic acid.
      • Which acid is commonly combined with formalin in order to fix and decalcify tissue simultaneously?
  • Determining the End-Point of Decalcification
      • Decalcification and End-Point Determination
      • Mechanical Methods of End-point Determination
      • Chemical Methods of End-point Determination
      • Radiography Method for End-point Determination
      • Weight Loss Method for End-point Determination
      • Post Decalcification
      • Failure to determine accurate decalcification end-point results in the loss of basophilia which subsequently leads to an increase in eosin staining, w...
  • Troubleshooting Calcified Tissue
      • Surface Decalcification
      • Inadequate Decalcification
      • Excessive Decalcification
      • Calcium that was not effectively decalcified stains bright pink with the H&E stain and does not hinder diagnosis rendering.
  • Summary of Decalcification
      • Summary
  • References
      • References

Additional Information

Level of instruction: Basic
Intended audience: Clinical laboratory histotechnologists, histotechnicians, and other medical laboratory personnel who have an interest in this subject matter. This course is also appropriate for histology and clinical laboratory science students, pathology residents, and practicing pathologists.
Author information: Diana Harrington, BS, HT(ASCP) is a histotechnologist at The Dermatology Center of Indiana. Since graduating from Indiana University, she has worked in various hospital laboratories as a medical technologist and histotechnologist. Her experience led her to teach IU students as a Clinical Education Supervisor and create the Histotechnology Program as Program Director for Keiser University in Florida.
Reviewer information: Carla J. Shoffeitt, MSM, HT(ASCP) is the Manager of the Pathology Department of Emory St. Joseph’s Hospital of Emory Healthcare in Atlanta, Georgia. She holds a Master of Science Degree in Healthcare Management as well as a Bachelor of Science degree in Biology from Troy University, Troy, Alabama. She is certified as a Histotechnician and has 25 years of experience in the field of Histology.
Course description: This course aims to simplify the decalcification process and provide useful techniques to work with calcified tissue successfully.

Just one user? Visit LabCE.com for individual subscriptions.
This course is part of:
Properly decalcified bone
Poorly decalcified bone
Properly/Poorly decalcified bone
Major components of bone