The invention relates to a system (1) for determining the quality of a bone structure (2) comprising: a body adapted for drilling through the bone structure a first electrode (11) arranged on the body so as to come into contact with the bone structure (2) during drilling a second electrode (12) arranged on the body so as to come into contact with the bone structure (2) at a distance from the first electrode (11) during drilling an electric generator (23) adapted to apply an electric current between the first (11) and second (12) electrodes for a pre determined period of time a measuring device (24) adapted to measure the electric current continuously and over the pre determined period and a processing device (28) adapted (i) to determine continuously and over the pre determined period an electrical magnitude representative of the aptitude of the bone structure (2) for allowing electric current to pass therethrough and (ii) to deliver continuously and over the pre determined period a signal representative of the quality of the bone structure (2) between the contact surfaces of the first (11) and second (12) electrodes using the determined electrical magnitude.
