Self-Heating Electric Plugger/Syringe Needle For Use In A Root Canal

Abstract

A self-heating electric plugger/syringe needle (10/70) with the conductive element (50) on the external surface of the needle (10/70) is described. The needle (10/70), which can be divided into shank (30) and tip (20) portions, is hollow and is made of an electrically resistive material. A conductive element (50) located on the external surface of the needle runs along the length of its shank (30) and the length of its tip (20). An insulating material (60) located between the conductive element (50) and the external surface of the needle runs along the length of the shank (30). The conductive element (50) contacts the tip (20) of the needle, causing the needle to self-heat when electric current is supplied. A method for filling a root canal using the self-heating electric plugger/syringe needle (10/70) is also described.

Claims

1. A self-heating electric plugger/syringe needle (10/70) comprising: a hollow needle made of an electrically resistive material, the needle having a shank (30) portion and a tip (20) portion; a conductive element (50) located on an external surface of the needle (10/70) and running along a length of the shank (30) portion and a length of the tip (20) portion of the needle (10/70); and an insulating material (60) located between the conductive element (50) and the external surface of the needle and running along the length of the shank (30) portion of the needle (10/70), wherein the conductive element (50) contacts the electrically resistive material of the needle (10/70) at the tip (20) portion, thereby heating the needle (10/70) when electric current is supplied to the conductive element (50).

2. A needle according to claim 1, wherein the conductive element (50) has a sinusoidal pattern.

3. A needle according to claim 1, wherein the conductive element (50) has a straight-line pattern.

4. A needle according to claim 1, wherein the electrically resistive material is stainless steel.

5. A method for filling a root canal, using a self-heating electric plugger/syringe needle (10/70), wherein a conductive element (50) located on an external surface of the needle (10/70) contacts a tip (30) portion of the needle (10/70) and causes the needle (10/70) to self-heat when electric current is supplied to the conductive element (50).

6. A self-heating electric plugger/syringe needle (10/70) comprising: a conductive element isolated from an electrically resistive shank portion of the needle (10/70) by an insulating material (60) wrapped about the shank portion, the conductive element extending past an end of the insulating material to contact the electrically resistive material at an electrically resistive tip (20) portion of the needle.

7. A needle according to claim 6, wherein the conductive element (50) has a sinusoidal pattern.

8. A needle according to claim 6, wherein the conductive element (50) has a straight-line pattern.

9. A needle according to claim 6 further comprising the electrically resistive shank and tip portions being stainless steel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a side view of an embodiment of a self-heating electric plugger/syringe needle made according to this invention.

[0013] FIG. 2 is a top view of the embodiment shown in FIG. 1.

[0014] FIG. 3 is an enlarged view of the tip of the embodiment shown in FIG. 1.

[0015] FIG. 4 is a side view of an alternative embodiment of a self-heating electric plugger/syringe needle made according to this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] As shown in FIGS. 1-3, the self-heating electric plugger/syringe needle 10 can be divided into a shank 30 portion and a tip 20 portion. The shank 30 may be tapered, with the diameter of the taper increasing as the distance from the tip 20 increases. The end of the shank 30 opposite the tip 20 may be connected to a handpiece (not shown) which delivers electric current to the conductive element 50 as well as providing a handle for the clinician to manipulate the electric heat plugger/syringe needle 10. The bore 25 of the needle 10 is hollow. A gutta percha syringe mechanism is located in the handpiece so as to pre-soften and push the thermo-plasticized filling material out through the hollow space 25 inside the plugger/syringe needle 10.

[0017] The self-heating electric plugger/syringe needle 10 is made of an electrically resistive material, preferably stainless steel. A sinusoidal-shaped conductive element 50, also known as a heating element, on the external surface of the needle 10 runs along the length of its shank 30 and the length of its tip 20. The conductive element 50 is separated from the surface of the needle 10 by an insulating material 60, which also runs along the length of the shank 30 of the needle 10. However, at the tip 20 of the needle 10, the conductive element 50 directly contacts the electrically resistive material of the needle 10 (i.e., the tip 20 is non-insulated). The electrically resistive material acts as a ground to the electric current which, because the electrically resistive material is more resistive to the current than the insulating material 60, causes the needle 10 to self-heat.

[0018] As shown in FIG. 4, an alternative embodiment of the self-heating electric plugger/syringe needle 70 has a shank 30 portion and a tip 20 portion. The shank 30 may be tapered, with the diameter of the taper increasing as the distance from the tip 20 increases. The end of the shank 30 opposite the tip 20 may be connected to a handpiece (not shown) which delivers electric current to the conductive element 50 as well as providing a handle for the clinician to manipulate the electric heat plugger/syringe needle 70. The bore 25 of the needle 70 is hollow. A gutta percha syringe mechanism is located in the handpiece so as to pre-soften and push the thermo-plasticized filling material out through the hollow space 25 inside the plugger/syringe needle 70.

[0019] The self-heating electric plugger/syringe needle 70 is made of an electrically resistive material, preferably stainless steel. A conductive element 50, also known as a heating element, on the external surface of the needle 70 runs in a straight line along the length of its shank 30 and the length of its tip 20. The conductive element 50 is separated from the surface of the needle 70 by an insulating material 60, which also runs along the length of the shank 30 of the needle 70. However, at the tip 20 of the needle 70, the conductive element 50 directly contacts the electrically resistive material of the needle 70 (i.e., the tip is non-insulated). The electrically resistive material acts as a ground to the electric current which, because the electrically resistive material is more resistive to the current than the insulating material, causes the needle 70 to self-heat.

[0020] While self-heating electric plugger/syringe needles have been described with a certain degree of particularity, many changes may be made in the components of the needles, the construction and arrangement of those components, and methods of using the needles without departing from the spirit and scope of this disclosure. The invention, therefore, is limited only by the scope of the attached claims, including the full range of equivalency to which each element thereof is entitled.