JP2561697B2 - Tool used in applying filling material to endodontically prepared root canals - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Conventional techniques for endodontic treatment of teeth are time consuming and often do not adequately guarantee that the entire root canal tissue will be filled with restorative material. Experience has shown that it is not possible to remove all pulp residues and contaminants from the root canal with current preparatory techniques. Endodontic treatment is successful if the pulp residue and contaminants are completely embedded in the restorative material. If the residue and contaminants are not completely buried, there is a high probability of failure in endodontic treatment. Complete burial of debris and contaminants requires complete occlusion of root canal tissue. Experience has shown that failure to completely occlude root canal tissue is a major cause of failure in endodontic treatment.

Incomplete occlusion of root canal tissue is mainly due to insufficient hydrostatic pressure to provide proper flow of filling material to root canal tissue due to irregularity of root canal tissue To do.
Root canals are rarely circular in cross section. Thus, the repair material inserted into the root canal must be able to compensate for the lack of circularity by flowing into the major diameter volume. Root canals often have lateral root canals and fissures that must be filled with repair material to ensure successful treatment. Hydrostatic pressure must be exerted on the restorative material to ensure the flow of restorative material into the lateral root canals and row grooves.

A common endodontic procedure uses a silver cone that is used with the paste to fill the irregularities. Silver is a highly malleable metal that bends and adapts to the curvature of the root canal. However, because the silver cones are manufactured with a truly circular cross section, they do not adapt to the most frequently occurring irregular cross section root canals. The silver cone cannot exert hydrostatic pressure on the sealer material and thus there is no satisfactory guarantee that the root canal and fissure are sealed.

Another common endodontic procedure uses a filling material, such as a gutta-percha, as the restorative material. Gutta percha is a semi-rigid material at normal room temperature. However, when heated, it loses rigidity and flows when force is applied to it. However, gutta percha does not hold the heat too long, thus this technique requires that a small amount of material be heated and packed into the root canal in a continuous manner by frequent reheating of the material in the root canal. . This process is slow and time consuming, and also carries the risk that the gutta percha deep in the root canal is not sufficiently heated by the above method and thus does not flow properly to the root canal irregularity.

Another common endodontic procedure is to use the Gutta Percha heating and injection device. This device is commonly referred to as the Gutta Percha Gun. The gun supplies gutta percha to the root canal under sufficient pressure to ensure that it is heated and the root canal irregularities are properly filled. The problem with this gun technique is that there is no satisfactory way to ensure that the restorative material is not extruded through the apex of the root canal and does not leave a tightly packed mass in the gums.

The technique by which restorative material can be applied to the entire root canal under sufficient hydrostatic pressure ensures that all lateral root canals and fissures are filled, and also with residual pulp material. It is clear to ensure that all the contaminants are well buried. Moreover, it is clear that if the technique adequately prevents extrusion of repair material through the apex of the root canal, it is an improvement over the known technique. further,
Clearly, if the technique is performed in a single operation, rather than continuously, there are significant time and thus economic advantages over known techniques. The invention described below provides these advantages.

The device of the present invention is in the form of a rigid carrier member coated with gutta percha or similar filling material. The carrier member is a tapered elongated bar. The carrier member may be constructed of any material that is sufficiently rigid and non-toxic when left in the root canal. One of the materials that has been successfully used is stainless steel. Plastic or aluminum carrier members also work well.

The carrier member incorporates a matte finish, or radial rib texture or helix to provide an attachment surface for the gutta percha and to serve as a mechanical piston to assist in pushing the gutta percha into the root canal.

In one embodiment, the tip of the carrier member intended for the apical portion of the root canal incorporates a sharp flat surface at the distal end. Thus, the carrier member is pushed into the root canal at a sufficient depth of the taper, the taper preventing the carrier member from rotating in the root canal. The shaft of the carrier member has a region of smaller diameter than its normal diameter. This point of small diameter or a region of reduced torque resistance is designed to break when a certain level of torque is applied to the handle of the carrier member. The flatness at the end of the carrier member is
The carrier member is prevented from rotating, thus breaking the member when torque is applied to the handle. The region of reduced torque resistance is located at a particular point on the carrier member at the desired level in the root canal. The portion of the carrier member shaft over the area of reduced torque resistance is of constant cross section (ie, not ribbed structure) and removal of the member from the semi-rigid gutta percha without pulling the gutta percha from the root canal. To facilitate.

A disk-shaped washer is incorporated into the shaft of the carrier member and acts as a stop plug in the root canal coronal opening and thus serves to prevent viscous outflow of gutta percha from the root canal during the insertion process.

The gutta percha is molded into the carrier member in a tapered or conical shape, typically with a sufficient amount of material to ensure complete filling of the root canal and thereby complete closure of the root canal. Easy to introduce into the root canal taper.

The device is manufactured in a variety of sizes to accommodate standard endodontic files.

In using the tool of the present invention, the root canal is first prepared in the usual manner by broaching with an endodontic file. The final rasp used in the preparation of the apex determines the proper gutta percha device. A properly sized carrier member is prepared with the gutta percha and the gutta percha is heated to the point where the surface becomes glossy. The heated device is then inserted into the root canal with a positive point force. Then the handle portion of the carrier member
It is rotated while maintaining the acuity until torsional damage occurs.

The shank of the carrier member is then removed, retaining the stop plug or washer against the tooth, and the rest of the endodontic treatment is completed using conventional procedures.

For more information on background materials related to the present invention, see Endodontics Journal, 1978.
Reference is made to pages 186 to 188 of Vol. 4, No. 6 of the year, where a new gutta percha technique is described in which gutta percha is formed around an endodontic file.

A further understanding of the invention will be obtained by reference to the following description and claims taken in conjunction with the accompanying drawings.

Referring initially to FIG. 1, a tool that is a carrier member is shown generally at 10 and has a proximal end 14
And an elongated shaft 12 having a distal end 16. The shaft can have a variety of cross sectional configurations, but the preferred and simplest shape is a circular cross sectional configuration as shown. At the distal end 16, the shaft is flared at 18 into a flattened or non-circular cross-sectional configuration so that when the shaft is positioned in the root canal of the tooth, as will be described more specifically below. The enclosed end portion 18 impedes rotation of the shaft. A plurality of (three illustrated) spaced apart enlarged cross-sectional dimension portions 20A-20C are integrally formed on the shaft. When the shaft is of circular cross section as preferred, the enlarged dimensioned portions 20A, 20B and 20C are also preferably of enlarged circular cross sectional configuration. An alternative arrangement (not shown), instead of the spaced apart enlarged cross-sections, includes an integral spiral portion extending from the shaft body.

A region 22 of reduced torque resistance is located between the enlarged dimension portion 20A and the proximal end 14. This is the shape of the groove formed around the shaft, as shown. groove
Between 22 and the proximal end 14 is a slide stopper or washer 24 with an opening 24A that slidably receives the shaft 12.

At the proximal end 14, a handle portion 26 is attached to the shaft.

The handle 26 has a larger diameter than the shaft 12,
It is then integrated with the shaft or fixed to the shaft and is made of a material such as plastic.

FIG. 2 shows an instrument ready for use in inserting a filling material, such as gutta percha, into the root canal of an endodontically prepared tooth. FIG. 2 shows in cross section the fill material 28 formed on the tool 10. Filling material 28 is a gutta percha-like material that can be manually formed on tool 10. After formation, Gutta Percha is flame-heated to the proper stage.

FIG. 3 shows a tooth 30 having root canals 32 and 34. Root canal 32
Was prepared endodontically with conventional techniques, such as by use of a file, to remove root pulp and prepare the root canal as clean as possible. The instrument formed with the tool 10 with the molded filling material 28 is ready to be used to fill the root canal 32. The apex of the root canal is shown at 36 and the crown or coronal portion is shown at 38.

4-6 show the continuation of the step of filling root canal 32.
FIG. 4 shows the instrument inserted into the root canal 32. Filling material 28
Is pushed in by the insertion of the appliance to fill the root canal up to the apical region 36 of the tooth. After full insertion of the instrument as shown in FIG. 4, a rotational torque is applied to the handle 26 to reduce the torque tolerance area as shown in FIG.
Cut the shaft at 22. This is possible because the flared distal end 18 of the shaft impedes rotation with respect to the tooth 30.

After the shaft is cut into two parts, the proximal part is withdrawn. The slide washer 24 is used to retain the filling material 28 in the root canal by holding the washer downward when the proximal end portion of the shaft 12 is retrieved.

FIG. 6 shows the proximal portion of the tool being retrieved. The washer 24 is then removed, leaving the distal portion of the shaft in place within the root canal 32. Root canal by applying mechanical or hydraulic pressure to the filling material to push it into the root canal.
32 can be filled more completely. The coronal region of the tooth can be filled in the usual way.

The depiction of tooth 30 in FIGS. 3-6 is merely exemplary, as the tooth may vary from individual to individual, and the drawings illustrate the relevant steps rather than accurately illustrating the appearance of the tooth or root canal. Is intended.

Thus, the present invention provides a unique and highly effective method of delivering filling material, such as gutta percha, to endodontically prepared root canals. While the prior art teaches the use of rasps as carriers for filler materials, this known method works successfully for its intended purpose, while
There are limitations and problems overcome by the present invention.

Figures 7-11 show a collection of alternative embodiments of the invention, preferably formed of plastic. The shaft 12 has an elongated tapered shape, where the distal end 16 is slightly rounded. The handle 26A is integrally formed with the shaft and has a non-circular cross section, such as a square, as shown in FIG. Obviously, the handle could also be a hexagon or other shape that allows the tool to be manipulated by an endodontist.

The outer surface of the shaft 12 of FIG. 7 is preferably formed with a matte finish so that the filling material formed thereon, as in FIG. 2, is applied to an endodontically prepared root canal. Fixed to shaft for insertion. Sliding washers are not shown in the embodiment of FIGS. 7-10, but washers are shown in FIGS.
Obviously, it can be used in the same way as shown in the figure.

The embodiment of Figures 7-10 does not include a flared end as for the embodiment of Figures 1-2, but the lower portion of the shaft is inserted into the root canal by the provision of a cut 40 formed in the shaft. After that, it can be disconnected. Cut 40 corresponds to the reduced diameter portion 22 of FIGS. 1-2 and provides stress points. After the shaft is inserted into the root canal, the lower part is moved back and forth with respect to the teeth,
It can be separated from the upper portion, where the lower portion is positioned to break the shaft at cut 40.

8-9 show an embodiment similar to that of FIG. 7, except for the reduced diameter recesses 42 which are spaced apart. In FIG. 8, the recess 42 has a curved peripheral bottom surface and is wide,
In FIG. 9, the recess 42A is much narrower. This indicates that the shape, size and spacing of the recesses are variable.

FIG. 10 shows an embodiment including an integrated enlarged diameter portion 44. These parts, as shown in FIGS.
It is semi-circular in the outer configuration as compared to the cylindrical configuration of the enlarged diameter portions 21A-20C. The enlarged diameter portion 44 serves to help retain the fill material on the shaft while the shaft is being inserted into the root canal.

The alternative embodiments of Figures 7-10 illustrate the fact that the tool can take a variety of configurations, each of which is within the scope of the present invention and for endodontically prepared root canals. It functions to allow easy and effective insertion of the filling material.

The claims in the specification describe the invention as submitted, and the terms used in the claims derive their meaning from the use of such terms in the specification. The same terms used in the prior art are:
It is broader in meaning than what is specifically used here. Whenever there is a question between the broader definition of such term used in the prior art and the more specific use of that term herein, it is meant in the more specific sense.

Although the present invention has been described with a certain degree of particularity, it will be apparent that numerous changes may be made in structural details and arrangement of components without departing from the spirit and scope of the disclosure. The invention is not limited to the embodiments shown here for purposes of illustration, but includes the full range of equivalents to which each element is entitled and is limited only by the scope of the claims.

 The main features and aspects of the present invention are as follows.

1. a tool used in applying a filling material, such as gutta percha or the like, to an endodontically prepared root canal of a tooth extending from the coronal region of the tooth to the root apex; An elongated shaft formed of a bio-resistant material, the shaft having a distal end portion and a proximal end portion, and the distal end having a tooth when the tool is inserted into a root canal. And a proximal end portion forming a handle portion, wherein the distal portion of the shaft is adapted to receive a filler material formed thereon. It is compliant and insertable into an endodontically prepared root canal, and the handle proximal end portion is severable from the distal portion, thereby allowing the distal portion and filling material to be cut within the root canal. A tool consisting of.

2. The tool according to 1 above, wherein the handle portion is dimensionally enlarged.

3. The tool according to 1 above, wherein the surface configuration at the distal end portion of the shaft is in the form of a matte finish.

4. The tool according to claim 1, wherein the shaft includes integrated, spaced apart, enlarged diameter portions at the distal end portion.

5. The tool of claim 1 wherein the elongate shaft includes integrated, spaced-apart, reduced diameter portions at the distal end portion.

6. The shaft has a cut between the distal end portion and the proximal end portion, the cut forming a point of weakness that may cause the proximal end portion of the shaft to break from the distal end portion. The tool as described in 1 above, which can

7. The distal end portion is non-circular in cross-section such that the proximal end handle portion is severable from the distal end portion by the application of rotational torque to the proximal end handle portion. Tools.

8. A filling material formed around a distal end portion, the filling material having a shape and dimensions for insertion by the shaft into an endodontically prepared root canal. tool.

9. In the shaft, comprising a reduced diameter area between the distal portion of the proximal end portion, the reduced diameter area comprising:
The tool of claim 1 which provides a means for facilitating cutting of the distal portion from the proximal portion.

10. The tool according to 2 above, wherein the handle portion is partially formed of a different material than the shaft.

[Brief description of drawings]

FIG. 1 is an enlarged front view of the tool or carrier member of the present invention. The tool includes a slidable stopper or washer shown in cross section. 2 is a front view similar to FIG. 1, showing the lower portion of the tool wrapped in a conical amount of filler material such as gutta percha. As shown in FIG. 2, the device is ready for use in filling endodontically prepared root canals. FIG. 3 shows a root canal in cross section showing an endodontically prepared tooth and a reduction, such as that used to apply a filling material to one of the endodonically prepared roots. FIG. 3 shows the device of the invention on a scale. FIG. 4 is a cross-sectional view of the tooth similar to FIG. 3 showing the appliance inserted into the root canal. Figure 5 shows the next step in the sequence of applying the filling material to the root canal, where the tool has been rotated to cut the proximal portion from the distal portion. FIG. 6 shows removal of the proximal portion of the tool with the distal portion retained in the root canal with filling material. 7 is a front view of an alternative embodiment of the tool of FIG. 1 wherein the tool shaft has a matte surface finish. Figure 8 is a front view of another alternative embodiment substantially similar to Figure 7, but in this case the shaft has spaced peripheral depressions. 9 is a front view of an embodiment similar to that of FIGS. 7-8 in which the shaft includes relatively closely spaced recesses as compared to the recesses of FIG. FIG. 10 is a front view of yet another embodiment including enlarged diameter portions spaced at the shaft. FIG. 11 is a view of the tool shown in FIG. 9 taken along line 11-11. In the figure, 10 ... Carrier member, 12 ... Extension shaft, 14
... proximal end, 16 ... distal end, 22 ... groove, 24 ... washer, 26 ... handle, 28 ... filling material, 30 ... teeth, 32 and 34 ... root canal, 36 …… Apex.

Claims (1)

(57) [Claims] 1. A tool for use in applying a filling material, such as gutta percha or the like, to an endodontically prepared tooth root canal extending from a coronal region of a tooth to a root apex. An elongated shaft formed of a material having a high biological resistance, wherein the shaft has a distal end portion and a proximal end portion,
And the distal end is sized to be positioned adjacent the apex of the tooth when the tool is inserted into the root canal; the proximal end forming the handle portion, where the shaft The distal portion is adapted to receive a filling material formed thereon and is insertable into an endodontically prepared root canal, and the handle proximal end portion is from the distal portion. A tool that is severable, thereby retaining the distal portion and filling material within the root canal.