All of us are quite aware of the word Dentist and hence with Dentin, we immediately can relate it to teeth and enamels. It is the calcified tissue present in the human body which is present along with cementum, pulp and enamel. Together these form the strongest and most long lasting structures in our body known as teeth. The dentin is the second layer on the teeth just below the enamel, has the topping of enamel located on the crown and is seated inside the cementum on root. The most important part of any tooth is Dentin and its color ranges between creamy white to yellow due to which our teeth appears white or yellowish. Dentin of the tooth comes from the crown and is attached to the root where it is covered by cementum and crowned by enamel.
Dentin resembles the bone structure and has closely packed channels or tubules that are present in zigzag manner throughout its density. The tubules are more densely packed towards the pulp of the tooth than at the surface. The cytoplasmic extensions emerging from odontoblasts are also present inside the dentin. The odonoblast creates the dentin and hence its cellular bodies are present lining the dentin’s inner portion and form the boundary of pulp.
Pulp is present inside the dentin or the dentin encircles the pulp. Dentin is essentially made up of mineral hydroxylapatite, some organic matter as well as water. Dentin is the main support for the enamel as it is comparatively less mineralized as well as less brittle. Dentile tubules which are the microscopic channels or canals inside the dentine have the roots placed outward from the pulp and join the cementum’s external portion which is present at periphery of the enamel. The dentin tubules encircle cellular structures and the fluid. Researchers are of the opinion that dentin formation (entinogenesis) precedes the formation of enamel and is stimulated by the odontoblasts present inside the pulp. The major highlight of the growth of dentin is that it goes on forming all through the life and only can be halted by the attrition or tooth decay problems.
The enamel is the crown of the dentin and hence it serves the function of protecting it. Whenever the enamel gets damaged, the dentin gets exposed due to which we suffer form sensitive teeth. These sensitive teeth are very problematic and on sudden exposure to temperature change or sweets, acids or harsh chemicals radiates extreme pain. Regular and careful brushing, gargling and flossing is the only way of warding off the infection and loss of enamel. When the infection penertrates the dentin it results in decay which is an extremely painful experience. It also sometimes leads to septicemia, the secondary infection related to the earlier one.
The developmental stage and appearance distinguishes the various types of dentins from each other. Primary dentins are the major part of tooth while the secondary dentins are formed later on when the root formation is complete. Tertiary dentin is created to respond biologically to stimuli.
Elephant’s ivory is a type of strong dentin. But it does not have the hardness of enamel and hence is usually used for making billiard balls, piano keys, carved artistic objects, jewelry and other various things. Earlier elephants used to be killed for ivory and hence there number decreased rapidly. But today, objects are only made from the ivory of naturally dead animals.