The method of establishing a drilling aid (16) involves the successive steps of taking an X-ray photograph of the jaw (1)； taking three-dimensional optical measurements of the visible, (13,14) surface of the jaw and teeth, representing the occlusal surfaces of adjacent teeth (11,12), and correlating the sets of data. The optimal drill-hole for an implant is determined preferably based on the X-ray. A guide hole in a drilling template is determined in relation to the surfaces of the adjacent teeth on the basis of the X-ray photo and optical measurement.
