Application of a Novel Colour Palette for Determination of End-point Decalcification of Hard Tissues: A Cross-sectional Study

Abstract

Introduction: Decalcification is a technique used to remove calcium salts from hard tissue specimens, such as bone or teeth, to make them suitable for sectioning. X-rays, physical methods, and chemical methods are commonly used to determine the endpoint of decalcification. However, these procedures can be cumbersome, may deteriorate the specimen, and are often subjective. Aim: To determine the endpoint of decalcification of hard tissue specimens using a colour palette. Materials and Methods: A cross-sectional study was conducted in the Department of Oral Pathology at Saveetha Dental College and Hospitals in Chennai, Tamil Nadu, India, over a period of 5 months. A total of 25 hard tissue specimens (10 bone and 15 teeth) were subjected to decalcification in 20% formic acid. To evaluate the endpoint of decalcification, silver nitrate solution was added to the formic acid, and the colour change was noted. The resulting colour was compared with a previously patented colour palette (Patent number: 202241047215). Once a lighter colour was obtained, the specimen was processed, sectioned, and stained using Haematoxylin and Eosin (H&E). The slides were then evaluated by two pathologists. Results: A total of 8 (80%) bone samples exhibited excellent staining, while 2 (20%) samples showed a good staining score. Regarding the tooth samples, 14 (93.3%) showed excellent staining, and one (6.66%) tooth displayed a good staining score. Conclusion: The present method is a simple and safe way to determine the endpoint of decalcification for a specimen. It does not damage the tissue, thus preserving the integrity of the hard tissue specimen.

Keywords

• calcium
• decalcified hard tissues
• pathology
• tooth