Enamel Composition and Function Quiz

Enamel Composition

• Enamel, the hard outer layer of teeth, contains primarily inorganic matter (96%)
• This inorganic matter is primarily calcium phosphate, often in the form of hydroxyapatite crystals.
• The organic matrix (4%) also plays a role, made up of proteins and glycoproteins.
• Proteins in the enamel matrix are classified as amelogenins and non-amelogenins.
• Amelogenins are a group of proteins, rich in proline and hydroxyproline.
• Non-amelogenins have a variety of functions and include proteins like enamelins and ameloblastins.
• The hydroxyapatite crystals have a hexagonal cross-section.
• Various ions like Al, Ba, Cu, and Mo also play a role but the exact role is unknown

Enamel Function

• The inorganic component of enamel gives it its hardness and resistance to acid dissolution.
• The organic component influences the process of mineralisation.
• The enamel surface is hard and resistant to acid dissolution by bacteria and thus prevents easy demineralisation.
• The subsurface and deeper layers contain Na, Mg, and CO3 molecules.
• These molecules help prevent water penetration and making enamel more resistant.