Anatomy of a tooth.

Hello and welcome to the journey of discovering " nothing but the tooth." Let me introduce you to the tooth. The tooth is made up of three layers:

ENAMEL :The outermost layer of each tooth is called Enamel. Enamel is the hardest substance of the human body. It comprises of hydroxyapatite crystals joined to each other.

When you use a fluoridated toothpaste these crystals absorb the fluoride from the toothpaste and become "fluorapatite" . Fluorapatite crystals are harder and stronger than hydroxyapatite crystals .

DENTIN : Dentin is the second layer of tooth beneath the enamel. It is yellow, tubular, bone-like structure and it is responsible for the colour of your tooth. The microscopic tubules in the dentin contain sensory nerves coming from the pulp tissue. Remember that dentin is a living tissue and it can grow and repair itself.

When there is a breach in the enamel surface due to caries/ erosion/ abrasion; these dentinal tubules get exposed to the environment which leads to tooth sensitivity. A toothpaste for sensitivity helps in blocking these tubules (sensory nerves) by depositing potassium nitrate crystals. These toothpastes also have added sodium fluoride which triggers the fluorapatite formation (reparative) and creates new barriers.

PULP : Pulp forms the core of each tooth. It gives the tooth its vitality and helps in providing nourishment to the dentin. It mostly consists of blood vessels and nerves (neurovascular). Due to continuous deposition of dentin the pulp keeps shrinking in size as you age.

Any injury to the pulp results in discolouration of the tooth to a blackish hue. Any infection reaching the pulp will result in tremendous pain and swelling of gums which then is treated by doing a root canal treatment by the dentist.

Next week we will learn "all about caries".