decalcification

Decalcification refers to the removal or dissolution of calcium salts, most often calcium carbonate or calcium phosphate, from a material. The term is used across disciplines, including biology, medicine, dentistry, and laboratory histology, to describe processes that reduce the mineral content of a substance.

In humans, decalcification commonly describes bone demineralization, where mineral content decreases due to physiological remodeling or pathological processes. Osteoclasts resorb bone; if formation cannot keep pace, bone mineral density declines, increasing fracture risk. Risk factors include aging, hormonal changes (estrogen deficiency after menopause), inadequate calcium or vitamin D, inactivity, corticosteroids, and diseases such as hyperparathyroidism.

In dentistry, demineralization of enamel or dentin occurs when acidic challenges from foods or bacterial metabolism dissolve mineral content, producing white spots and caries and potentially leading to cavities if progression continues. Early demineralization may be reversible with proper remineralization strategies and good oral hygiene.

In histology and laboratory practice, decalcification is a preparatory step to enable sectioning of calcified tissues. Agents include mineral acids (formic, nitric, or hydrochloric) or chelating agents (EDTA). Acid methods are faster but may compromise tissue morphology and antigenicity; chelation preserves structure but is slower. Processing outcomes depend on tissue type, specimen size, and the intended downstream analyses.

Diagnosis and management focus on maintaining mineral balance for bones, minimizing acidic challenges for teeth, and selecting appropriate decalcification methods for tissue analysis. Prevention includes adequate nutrition, physical activity, dental hygiene, fluoride use, and treatment of underlying endocrine disorders.