A computer-implemented method of planning of the shapes of free-form tool paths (P) for simultaneous two-sided machining of a dental restoration (1) having an individual free-form target geometry from a workpiece (2) by using a dental tool machine (3) having at least two tool spindles each having at least one tool (4) arranged on a different side of the workpiece (2) which is simultaneously movable along an axis (y) relative to the tools (4) thereby imposing a kinematic axis coupling. The method includes a step of determining transformations (T′, T″) of the target geometry by which the kinematic axis coupling is converted into a common coupling parameter for both tools (4); and a step of generating dependent on these transformations (T′, T″) the shapes of the free-form tool paths (P) in which the common coupling parameter is identical in time for all participating tool spindles that are driven simultaneously.