What is cementum ?
The cementum is basically a calcified mesenchymal tissue that surrounds the root of the tooth and serves as the site of insertion for the periodontal ligament, thus connecting the tooth to the alveolar bone. There are two types of cementum: one, acellular, at the upper part of the dental root, and the other, cellular, in the apical region. Cementum is secreted by the cementoblasts and is formed by the apposition of small parallel layers. A greater thickness of cementum is usually found in the areas where the tooth receives greatest pressure. Collagen fibers are present within the cementum; in the acellular cementum they are extrinsic and are derived from the periodontal ligament whereas, in the cellular cement, they are intrinsic and are formed by the cementoblasts (1)(2)(4)