Teeth are the hardest substance in the human body.The parts of the teeth are Enamel, Dentin, Pulp, Cementum and Periodontal ligament. Enamel is the hardest, highly mineralized tissue of the body. 96% of enamel consists of mineral and 4% water and the other organic material. The normal color of enamel varies from light yellow to grayish white. Dentin is the substance between enamel or cementum and the pulp chamber. It is secreted by the odontoblasts of the dental pulp. Cementum is a specialised hard tissue covering the root of a tooth. Dental Pulp is a specialized mesenchymal connective tissue which has a rich vascular, lymphatic and nerve supply.It occupies the central pulp cavity of each tooth.It provides vitality to the tooth.The other functions are inductive, protective and formative. The periodontal ligament, commonly abbreviated as the PDL, is a specialized connective tissue comprising of fibers that essentially attach a tooth to the alveolar bone.