Abstract: Disclosed is a drilling device and a method for the drilling of human or animal bone tissue. The method comprises the following steps; (a) providing a drill having an electrically conductive bone cutter and an electrically conducting nosepiece assembly spaced apart from the electrically conductive bone cutter and acting as a counter electrode; (b) placing the electrically conductive bone cutter and nosepiece assembly into contact with the bone tissue to be drilled; (c) measuring the electrical impedance between the bone cutter tip and the nosepiece or the current through the cutter motor; (d) commencing drilling and moving the bone cutter toward the bone surface; (e) starting a step counter when the impedance reduces or the cutter motor current increases; (f) incrementing the step counter with every step of the vertical drive motor until the step count reaches the prespecified value thereby controlling the depth of the hole drilled.

Abstract: Disclosed is a drilling device and a method for the drilling of human or animal bone tissue. The method comprises the following steps; (a) providing a drill having an electrically conductive bone cutter and an electrically conducting nosepiece assembly spaced apart from the electrically conductive bone cutter and acting as a counter electrode; (b) placing the electrically conductive bone cutter and nosepiece assembly into contact with the bone tissue to be drilled; (c) measuring the electrical impedance between the bone cutter tip and the nosepiece or the current through the cutter motor; (d) commencing drilling and moving the bone cutter toward the bone surface; (e) starting a step counter when the impedance reduces or the cutter motor current increases; (f) incrementing the step counter with every step of the vertical drive motor until the step count reaches the prespecified value thereby controlling the depth of the hole drilled.

Abstract: The present invention relates to methods and devices for formation of microconduits in tissue, particularly using an impedance sensing drill to form microconduits. One embodiment of the invention is an impedance sensing drill comprising a drilling assembly, a control module, mechanically connected to the drilling assembly for controlling the depth of drilling by the drilling assembly; and a sensor, electrically connected to the drilling assembly and control module for detecting a change in an electrical impedance of a material being drilled. Another embodiment is a method of forming a microconduit in a material, which comprises the steps of drilling into the material, monitoring an electrical impedance of the material, and stopping the drilling into the material when a change in the impedance is detected, thereby forming microconduit.