An implant device for engagement with a bone of a subject, said implant device comprising a distal end, a proximal end, a central shaft extending therebetween and a longitudinal central axis; said implant device further including a helical thread portion extending circumferentially about said central shaft and extending in a direction of from the distal end of the implant device and towards the proximal end thereof, and a root at the base of the helical thread portion adjacent the central shaft of the implant device, said helical thread portion in cross section including: a leading edge and a trailing edge, both of which extend at least radially outwardly from the central shaft and define the thread portion therebetween, whereby the root of the thread portion is defined therebetween in a direction of the longitudinal central axis of the implant device; and a crest portion disposed between the leading edge and the trailing edge and wherein said crest portion forms a radially outward portion of the thread portion, and wherein, wherein the crest portion provides an engagement surface for abutment and engagement with bone of a subject radially disposed at said thread portion; wherein said leading edge faces in a direction of at least towards the distal end of the implant device, and wherein said trailing edge faces at least in a direction towards the proximal end of the implant device; wherein a portion of the leading edge extends in a direction towards the distal end of the implant device further than the most distal portion of the root of the thread portion and wherein the distance in the longitudinal direction from the most proximal portion of the root to the most distal portion of the leading edge is greater than the longitudinal length of the root, such that said portion of the leading edge forms a recess between the central shaft and the leading edge; wherein the portion of said leading edge defining said recess between the central shaft and the leading edge provides for abutment and engagement with bone tissue of a subject disposed within said recess; wherein the trailing edge extends in a direction of from the most proximal portion of the root in a radial outward direction and towards the distal end; characterised in that the leading edge of the thread portion includes a first facet and a second facet for abutment and engagement with bone tissue of a subject, wherein the second facet has a substantially planar surface and is disposed between the root of the thread portion and the first facet, and extends radially outwardly from the shaft substantially normal to the longitudinal central axis of the implant device towards the first facet; and the first facet has a substantially planar surface and extends substantially radially outwardly from the second facet and extends towards the crest portion. a leading edge and a trailing edge, both of which extend at least radially outwardly from the central shaft and define the thread portion therebetween, whereby the root of the thread portion is defined therebetween in a direction of the longitudinal central axis of the implant device; and a crest portion disposed between the leading edge and the trailing edge and wherein said crest portion forms a radially outward portion of the thread portion, and wherein, wherein the crest portion provides an engagement surface for abutment and engagement with bone of a subject radially disposed at said thread portion; wherein said leading edge faces in a direction of at least towards the distal end of the implant device, and wherein said trailing edge faces at least in a direction towards the proximal end of the implant device; wherein a portion of the leading edge extends in a direction towards the distal end of the implant device further than the most distal portion of the root of the thread portion and wherein the distance in the longitudinal direction from the most proximal portion of the root to the most distal portion of the leading edge is greater than the longitudinal length of the root, such that said portion of the leading edge forms a recess between the central shaft and the leading edge; wherein the portion of said leading edge defining said recess between the central shaft and the leading edge provides for abutment and engagement with bone tissue of a subject disposed within said recess; wherein the trailing edge extends in a direction of from the most proximal portion of the root in a radial outward direction and towards the distal end; characterised in that the leading edge of the thread portion includes a first facet and a second facet for abutment and engagement with bone tissue of a subject, wherein the second facet has a substantially planar surface and is disposed between the root of the thread portion and the first facet, and extends radially outwardly from the shaft substantially normal to the longitudinal central axis of the implant device towards the first facet; and the first facet has a substantially planar surface and extends substantially radially outwardly from the second facet and extends towards the crest portion.