Abstract: A dental apparatus provided with a drive unit for operative dentistry instruments, specifically a powered system for performing the various phases of operative dentistry operations. This advanced dental apparatus is essentially characterized in that the working tool housed in a tool-holder sleeve, exhibits dampable, disengageable, reciprocating helical motion using a flexible cam. The cam is mounted on the rotational axis and its end is received in a hole in the sleeve. This device allows completely safe operative dentistry operations to be performed, while preventing false canals and instrument breakage, through the use of the flexible movement control device.