The invention relates to an intra-osseous implant for placement in bone of a human or animal body comprising at least one intra-osseous part intended for placement in said bone tissue having an apical side and a cervical side and composed of a body friendly material, which part is provided on its circumferential surface with a thread running in the direction of the apical end and a support part present at said cervical side of said at least one intra-osseous part intended for supporting a prosthetic element. The invention aims to provide a medical intra-osseous implant and especially a dental intra-osseous implant, which allows an accurate implant position at a desired depth into bone tissue, providing without losing a high degree of primary implant stability. To this end according to the invention the intra-osseous part is provided with one or more grooves extending in longitudinal direction and interrupting the screw thread into multiple interrupted screw thread parts, said multiple interrupted screw thread parts serving as retention elements allowing the placement of the implant in longitudinal direction into said bone tissue but preventing the removal of the implant in opposite longitudinal direction out of said bone. The invention can also be describes as an intra-osseous implant with along its circumferential surface several rows of retention elements situated in a longitudinal formation. At the same time these retention elements are situated in a screw thread configuration.
