Screwdriver and screw member adapted therefore

A screwdriver for fastening dental structures to dental implants, said screw driver comprising a central axis, a handle portion and a shaft portion, with a distal end attached to said handle portion and a proximal end attached to a tip portion for driving a screw member with rotation transmitted from said handle portion, said tip portion having a distal end attached to the shaft portion and a curved proximal end with a proximal end point wherein

• said tip portion has a substantially rounded cross-section in an axial plane, and a substantially polygonal shaped cross-section in a radial plane with at least a first and a second diagonal, extending perpendicularly to two opposite sides of the polygonal, respectively, wherein said first diagonal is greater than said second diagonal, the rounded cross-section in an axial plane resulting in a first curved portion and a second curved portion, respectively, extending from the distal end of the tip portion towards the proximal end of the tip portion, wherein the first curved portion ends at a distance from the proximal end point, such that a proximal end point of the first curved portion is located at a greater distance from the central axis in a radial plane than the distal end point of the curved proximal end.