Question

The amount of water in enamel is--------%
A. 90 - 92%
B. 75 - 80%
C. 40 - 50%
D. ≈ 3%

Answer 1

Hint: Dental enamel is the toughest material in the human body and acts as the dental crown's wear-resistant outer coat. It acts as an insulator, shielding the tooth from physical, thermal, and chemical pressures that would otherwise damage the vital tissue in the underlying dental pulp. Dental enamel is the only epithelial-derived tissue in mammals that mineralizes in non-pathological conditions (bone and dentin, the other principal mineralized tissues, are derived from mesenchymal cells).

Complete answer:
Enamel is the toughest substance in the animal world. Enamel is an ectodermal tissue. It is secreted by ectoderm Ameloblast cells. It contains the greatest quantity of inorganic salt (96 percent). Phosphate and carbonate of Ca, Mg, Na, and K are the most common inorganic salts. The enamel contains 3 percent water. Keratin and ossein are both present in the teeth. Ossein is a bone protein, and the remaining portion of the tooth emerges from the embryonic mesoderm.

- Option A is 90-92% but this is the percentage of Hydroxyapatite in enamel. Hence this is incorrect
- Options B and C are 75-80% and 40-50% but the amount of water present in enamel is 3-4%. Hence they are also incorrect
- Option D is ≈ 3%. This is the correct option. The other options have incorrect percentages of water found in enamel. As a result, options A, B, and C are incorrect.

Enamel is the human body's toughest material, extracted from ectodermal ameloblasts. It has a marginal water content (≈ 3 percent). As a result, option D is right.

Note: Amelogenesis is the mechanism by which enamel is formed.
- Ameloblasts secrete enamel matrix proteins into the enamel space, which are then degraded and proteolytically removed by ameloblasts.
- Ameloblasts control the creation of a de novo hydroxyapatite-based (Hap-based) inorganic substance within the enamel space with great precision.
- The developed enamel has a distinct prismatic appearance made up of rods.