Ossification is a medical term that is synonymous with bone tissue formation. Endochondral ossification and intramembranous ossification are two processes resulting in the formation of normal, healthy bone tissue. Heterotopic ossification is a process resulting in the formation of bone tissue, that is often atypical, at an extraskeletal location. Calcification is a medical term that is often confused with ossification. Calcification is synonymous with the formation of calcium-based salts and crystals within cells and tissue. Calcification is a process that occurs during ossification, but not vice versa.

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