Question

What is the chemical name of the substance that forms the tooth enamel in the human body?

• A. Calcium
• B. Sodium
• C. Calcium hydroxyapatite
• D. Hydrochloric acid

Answer 1

Answer:

C. Calcium hydroxyapatite

Composition of Tooth Enamel

• The primary chemical compound that constitutes tooth enamel is Calcium hydroxyapatite.
• Its chemical formula is denoted as Ca₁₀(PO₄)₆(OH)₂.
• This mineral form of apatite is highly crystalline and extremely hard, making it the hardest substance in the human body.

Mineralogical Details

• Calcium hydroxyapatite is a form of apatite, a phosphate mineral.
• It is primarily composed of calcium (Ca²⁺), phosphate (PO₄^3-), and hydroxide (OH^-) ions.
• The high concentration of calcium and phosphate ions contributes to the strength and rigidity of the enamel.

Significance in Dentistry

• The structure of enamel, based on hydroxyapatite crystals, is crucial for its function in protecting the underlying dentin and pulp.
• Factors like diet (acidic foods and drinks) and oral hygiene can affect the integrity of hydroxyapatite, leading to demineralization and dental caries.
• Fluoride ions can integrate into the enamel structure, forming fluorapatite, which is even more resistant to acid attacks than hydroxyapatite. This is a key principle in dental caries prevention.