toothroot

Toothroot refers to the portion of a tooth that anchors it within the jawbone. It is covered by cementum and lies beneath the gingiva, connected to the crown at the cementoenamel junction. The root contains the root canal system, which houses dental pulp during life and extends from the pulp chamber in the crown to the apex of the root. Depending on the tooth type, there may be one or more roots. Incisors and canines typically have a single root, premolars often have two, and molars usually have two or three, though variations occur.

The hard tissues of the root include dentin as the main substance, with a superficial layer of cementum. Cementum is a mineralized, avascular tissue that provides the surface for attachment of the periodontal ligament via Sharpey's fibers, enabling tooth stability while allowing a degree of mobility. The periodontal ligament suspends the tooth in its socket and distributes occlusal forces to the surrounding bone.

Root development begins after crown formation and is guided by Hertwig’s epithelial root sheath. Root length and apical closure progress as dentin and cementum are deposited toward the root apex, which contains the apical foramen through which nerves and blood vessels enter the pulp.

Clinical relevance includes root canal therapy, which treats infection or inflammation within the root canal system, and considerations of root morphology in procedures such as endodontic treatment and tooth extraction. Pathologies affecting the root include root resorption and fractures, which can compromise tooth stability.