Histology of the Teeth and Surrounding Structures

Teeth consist for the major part of dentin. This material houses the dental pulp, the soft tissue core of the tooth consisting of myxoid connective tissue with blood vessels and nerves, and supports the enamel cap that covers the part of the tooth that is exposed to the oral cavity. In the root area, dentin is covered by cementum that fixes the collagenous fibres of the periodontal ligament onto the root surface. At the other side, these collagenus fibres are attached to the bone of the tooth socket and in this way, the tooth is fixed in 
the jaw. Trough an opening at the root tip that is called the apical foramen, the connective tissue of the pulp is continuous with the collagenous fibres of the periodontal ligament. Blood vessels and nerves pass through this opening to the dental pulp. Sometimes, additional communications exist between dental pulp and the periodontal ligament. These so-called accessory canals are clinically important as they may cause lesions usually confined to the root tip to occur at aberrant sites.