what part of the tooth is composed of cellular tissue similar to bone, but harder?
Dentin is found underneath the enamel surface of the tooth and underneath the cementum that forms along a tooth's roots. Made of living cellular material and tissue, dentin is what makes up the majority of a tooth's structure. Dentin is a bone-like substance that contains microscopic tubules. Unlike enamel, exposed dentin is highly susceptible to the bacteria that cause dental cavities and can cause tooth sensitivity. Cementum.