Precision microneedling device and methods of use

A method of inserting a microneedle into human or animal tissue comprising the steps of:

• providing a microneedling device, said device comprising:
• (a) a housing that includes a microneedle assembly and an electrically conductive nosepiece assembly to be placed in contact with tissue to be microneedled;
• (b) a microneedle moved by an electric motor which is mobile in translation in the housing and wherein the microneedle is electrically conductive and is adapted to be moved into and out of the tissue being microneedled;
• (c) a control module electrically connected to the microneedle assembly for controlling the translation of the microneedle in the housing and into and out of the tissue being microneedled;
• (d) a sensor, electrically connected to the microneedle assembly and to the control module for detecting a change in an electrical impedance between the microneedle and the surface of the tissue being microneedled;
• wherein the sensor, upon detection of a change in the electrical impedance corresponding to a transition between air (no load;
• high electrical impedance) and tissue surface, sends a signal to the control module to begin incrementing a step counter;
• (e) automatically reverse the direction of the vertical drive motor when the step counter reaches a prespecified count, thereby withdrawing the microneedle from the tissue being microneedled, and thereby controlling the depth of the microneedled hole;
• and inserting the microneedle into the tissue with said microneedling device, wherein the microneedle is moved toward and away from the microneedling by a vertical drive motor that comprises a stepper motor.