0000917 - The Crystalline Composition of Human Tooth Enamel

Human tooth enamel, the outermost layer of our teeth, is an extraordinary substance known for its remarkable strength and durability. This remarkable substance is composed primarily of hydroxyapatite, a crystalline calcium phosphate mineral. But what makes tooth enamel so unique is the way these crystals are arranged: they form a tightly packed, interlocking structure that is resistant to wear and tear.

Each hydroxyapatite crystal in tooth enamel is about 50 nanometers long and 5 nanometers wide, arranged in a parallel fashion to one another. This highly ordered arrangement contributes to the exceptional strength of tooth enamel, making it the hardest tissue in the human body. It is more resistant to acid erosion than most other materials in the body, including bones.

The crystalline structure of tooth enamel also plays a role in its translucency. When light strikes the enamel surface, it interacts with the hydroxyapatite crystals, causing a portion of the light to be scattered and reflected, while the remaining light penetrates deeper into the tooth structure. This interplay of light with the crystals gives tooth enamel its characteristic pearly white appearance.

Interestingly, tooth enamel is not a static structure but undergoes continuous remodeling throughout our lives. Specialized cells called ameloblasts secrete new enamel crystals, while other cells dissolve old crystals, allowing for the repair of minor damage and the maintenance of optimal enamel health.

The unique crystalline composition of human tooth enamel is a testament to the intricate design of the human body. Its strength and durability enable us to bite, chew, and process food efficiently. Without this remarkable material, our teeth would be far more vulnerable to damage and decay, significantly impacting our overall health and well-being.