Tooth

A tooth is a mineralized organ composed of both hard and soft tissues, structurally divided into the crown (visible above the gum) and the root (embedded in the alveolar bone).

The outermost layer of the crown is enamel, the hardest tissue in the human body, produced by ameloblasts and composed primarily of hydroxyapatite crystals. Beneath the enamel lies dentin, a less mineralized but resilient tissue produced by odontoblasts, which extends throughout the crown and root and surrounds the central pulp chamber. Covering the root is cementum, a bone-like tissue produced by cementoblasts that anchors the tooth to the surrounding alveolar bone via the periodontal ligament.

The central portion of the tooth is the dental pulp, a soft connective tissue containing blood vessels, nerves, and various cell types, which provides nutrition and sensory function. The tooth is supported by the periodontium, which includes the cementum, periodontal ligament, alveolar bone, and gingiva.

Each tooth type (incisor, canine, premolar, molar) has characteristic anatomical features, including variations in crown shape, root number, and internal canal morphology, which are critical for function and clinical identification.