Which is regarded as the hardest substance in a human body that is made up of Calcium phosphate and does not dissolve in water?

The correct answer is Tooth Enamel.

Key Points

• Tooth enamel is the hardest substance in the human body and primarily composed of Calcium Phosphate.
• It is highly durable and resistant to wear, ensuring the protection of the inner layers of teeth like dentin and pulp.
• Despite its strength, enamel has no living cells, making it incapable of self-repair if damaged.
• Its primary role is to protect the teeth from the effects of chewing, biting, grinding, and exposure to acids and extreme temperatures.

Additional Information

• Calcium Phosphate:
  • It is the mineral that makes up the majority of enamel's composition, lending it strength and rigidity.
  • Calcium phosphate is insoluble in water, which is why enamel resists dissolution under normal conditions.
• Dentin:
  • The layer beneath the enamel that is less mineralized and more prone to decay if enamel wears away.
• Dental Health:
  • Enamel erosion can occur due to acidic foods, sugary drinks, or improper oral hygiene practices.
  • Fluoride treatments strengthen enamel by promoting remineralization.
• Comparison to Other Body Parts:
  • While enamel is the hardest substance in the body, bones are also composed of calcium but are less dense and have living cells for repair.