Thermal Incision Apparatus, System and Method

A method for making a thermal cutting surgical instrument system operable at a preselected and resistance-feedback controlled temperature for incising tissue without a mechanically sharp cutting edge and for sealing transected blood vessels, comprising the steps of:

• providing a blade supported by a handpiece, the blade having a heated portion, a support portion, and incorporating a first substrate of high thermal conductivity material in the heated portion of the blade,
• joining the first substrate of high thermal conductivity material to a second substrate of low thermal conductivity material in the support region of the blade, the first substrate of high thermal conductivity material having a first surface, and second substrate of low thermal conductivity material having a first surface;
• disposing an electrically insulative dielectric layer on the first surface of the first substrate of high thermal conductivity material and on the first surface of second substrate of low thermal conductivity material;
• disposing an electrically resistive heating element on the electrically insulative dielectric layer disposed on first substrate of high thermal conductivity material;
• disposing electrically conductive power leads and electrically conductive sense leads on the electrically insulative dielectric layer disposed on the second substrate of low thermal conductivity material in the support region of the blade and that are in electrical communication with the electrically resistive heating element, the electrically conductive power leads and electrically conductive sense leads each having a distal portion;
• disposing an electrically insulative dielectric overcoat layer on the electrically resistive heating element disposed on the electrically insulative dielectric layer disposed on first substrate of high thermal conductivity material and on the distal portion of the electrically conductive power leads and electrically conductive sense leads,
• wherein the electrically insulative dielectric layer, the electrically resistive heating element, the electrically conductive power leads and electrically conductive sense leads, and the electrically insulative dielectric overcoat layer can be moved repeatedly between air, tissue, blood, or other liquid without fracturing while the electrically resistive heating element is at a preselected elevated temperature.