Dentin is a Light Yellowish Viscoelastic material made up of Inorganic (Hydroxyapetitie) and Organic (collagenous fibrils and mucopolysaccharides) material which is harder than bone. Dentin thickness is 3-10 mm based on the location. Dentin is made up of dentinal tubules which are S shaped and perpendicular to Dentino enamel junction and Cementoneamel junction. Dentin is [&hellip