An intervertebral prosthesis or disk prosthesis comprising a front side, a
rear side, an upper side which can be placed on the base plate of
vertebral body, a lower side which can be placed on the base plate of a
vertebral body, a right side, a left side, a cavity which can receive a
fluid hydraulic osteocementum, an opening in the cavity and several
outlets out from the cavity. The total of the transversal surfaces of the
outlets SV on the front side, the total of the transversal surfaces of
the outlets SH on the rear side, the total of the transversal surfaces of
the outlets SR on the right side and the total of the transversal
surfaces of the outlets on the left side satisfy the following
conditions: SL>SR or SR>SL or SH>SV or SV>SH.