In the teeth, Sharpey's fibres are the ends of principal fibres that insert into the cementum. A study on rats suggests that the three-dimensional structure of Sharpey's fibres intensifies the continuity between the periodontal ligament fibre and the alveolar bone (tooth socket), and acts as a buffer medium against stress. Sharpey's Fibres in the primary acellular cementum are mineralized fully; those in cellular cementum and bone are mineralized only partially at their periphery.
In the skull the main function of Sharpey's fibres is to bind the cranial bones in a firm but moveable manner; they are most numerous in areas where the bones are subjected to the greatest forces of separation. In the spine, similar fibres join the intervertebral disk to the adjacent vertrebrae. Each fibre is accompanied by an arteriole and one or more nerve fibres.
English anatomist William Sharpey described them in 1846.