SummaryThe results are presented of research into the efficiency of various forms of dental burs. This research was carried out at the Delft University of Technology in collaboration with the Subfaculty of Dentistry of the Free University of Amsterdam. The process efficiency was measured during burring of both human teeth and amalgam plugs, with diamond burs and tungsten carbide burs at different speeds and diameters of the bur. Only the efficiency of the cutting process was evaluated, disregarding a number of other essential aspects of the burring process, such as the remaining surface quality after burring and the vibrations generated during burring.