Patent ID: 8215955

Claim:
An endodontic instrument for root canal filling, comprising: a body including a direct current (DC) power source and a printed circuit board; a heating tip connected to the body; a switch for operating the heating tip; and a control circuit for switching on/off power supply applied to the heating tip, wherein the heating tip includes: a first metal part serving as a resistant tube; a third metal part provided in a tube type and disposed inside the first metal part and configured to supply thermoelectric power and serve as a (−) terminal of a thermocouple; a second metal part disposed inside the third metal part in a form of wire and configured to supply the thermoelectric power, check a thermoelectric power (+) terminal, and serve as a (+) terminal of the thermocouple; a thermocouple junction in which one end of the second metal part and one end of the third metal part contact each other; a first insulator disposed inside the first metal part and enclosing a surface of the third metal part; a second insulator disposed inside the third metal part and enclosing a surface of the second metal part; a first conductive tube contacting the other end of the second metal part; a second conductive tube contacting the other end of the third metal part; and a third insulator connected and fixed to the first and second conductive tubes, wherein temperature is detected using the thermoelectric power of the thermocouple of the second and third metal parts.