An implant (1) is arranged with a thread (9) which can be exposed to a jaw bone (2) and which has a first extent (L) in the longitudinal direction of the implant. Thread flanks (3, 4) are assigned second extents (R-R1) between the inner and outer peripheries of the thread. Along all or most of the first extent (L), the thread flanks are arranged with one or more grooves (5, 6) extending preferably in the peripheral direction and situated on the second extents (R-R1). The groove or grooves are arranged to participate in the process by which the implant fuses with the jaw bone (2). In this way, a better or optimized fusion function and retention function is obtained for the implant in the jaw bone.
