JPH0246331Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention relates to a root canal insertion instrument used in dental treatment.

(Prior art) Generally, when treating cavities, the tooth is cut and a hole is made, and the pulp inside the root canal at the root side of the tooth and the pulp chamber at the tip side of the tooth is removed through this hole. After cleaning (cleansing), rotating the inner wall of the root canal (reaming), or reciprocating the root wall in the longitudinal direction (filing), the root canal and pulp chamber are filled with a filling material.

In order to prevent tooth decay from recurring, it is necessary to completely remove the infected part of the root wall along the entire length of the root chamber by reaming, etc. If the apical periodontium is lacerated by protrusion from the apical foramen (over-instrument), it will cause periodontitis, which is undesirable.

Therefore, conventionally, the initial cutting with a reamer or the like is made short, and the length of the uncut part or the total length of the root canal is measured.
Based on this measurement result, the uncut portion is cut again using a reamer or the like.

As a method for measuring the length of the uncut portion or the total length of the root canal, the following two methods have conventionally been widely adopted.

One method is to measure by X-ray photography, in which X-ray photography is performed with a stainless steel thin wire root canal insertion instrument inserted into the root canal, and the results are determined from the X-ray film image taken. This is the method for finding the above length.

The other method is electrical measurement,
A weak DC voltage or high frequency is applied between the root canal insertion instrument similar to the above inserted into the root canal and the patient, and the electrical resistance value between the tip of the root canal insertion instrument and the gingiva is measured. This is a method of determining the length by measuring the change in impedance due to capacitance or capacitance. Even when using this electrical method, check whether the root canal insertion instrument is inserted correctly into the root canal, that is, whether the reamer etc. has penetrated the root wall and perforated the tooth structure during cutting. For this purpose, X-ray photography is also used.

(Problems to be solved by the invention) However, since the above-mentioned conventional dental root canal insertion instrument has a stainless steel insertion part into the root canal,
There is a drawback that the image on the X-ray film obtained by X-ray photography is unclear, making it inaccurate to measure the length from this image, or making it difficult to judge whether the root canal insertion instrument is inserted correctly. Ta.

(Means for solving the problem) This invention was made to solve the above problem, and its gist is to provide a dental root canal that is inserted into the root canal of a tooth and used for X-ray photography. A dental root canal insertion instrument is characterized in that the root canal insertion portion is made of tungsten.

(Function) Tungsten has a significantly higher
When a dental root canal insertion instrument whose insertion part is made of tungsten is inserted into a root canal and taken an X-ray image, the insertion part is clearly visible on the X-ray film.

(Example) Hereinafter, an example of this invention will be described based on the drawings of FIGS. 1 and 2.

In FIGS. 1 and 2, 1 is a dental root canal insertion instrument, and the dental root canal insertion instrument 1 includes a roughly gourd-shaped gripping tool 2 and an insertion part 3 fixed to the gripping part 2.
and a disk-shaped stopper 4 supported in a press-fitted state in the insertion portion 3. The grip portion 2 is made of plastic, the stopper 4 is made of rubber, and the insertion portion 3 is made of pure tungsten.

It is generally known that when X-ray photography is performed, a substance with a higher specific gravity does not transmit X-rays and has better contrast performance. Tungsten has a higher specific gravity than stainless steel, so it has better contrast properties, and
It is the most suitable material for the insertion portion 3 because it is inexpensive and easily available, and also because it is non-toxic and highly safe.

The insertion portion 3 is formed to have a circular cross section, with a straight portion 3a at the base and a tapered portion 3c tapered from the end of the straight portion 3a toward the tip 3b. Further, the cross-sectional diameter of the insertion portion 3 is set to 0.06 to 0.8 mm, which is smaller than the diameter of a general reamer or the like.

Further, the tip 3b is formed in a hemispherical shape,
When inserting the insertion portion 3 into the root canal 6 of the tooth 5, it will not pierce the root wall, which is the inner peripheral surface of the root canal 6, and become unable to enter. Furthermore, since this insertion part 3 is made of ultra-fine tungsten, it has high flexibility and restorability, and can be smoothly inserted into and removed from the root canal 6.
Further, even after being removed from the root canal 6, the straight shape is restored.

In addition, the pulp in the root canal 6 and pulp chamber 7 of the tooth 5 has been removed by cleansing, and the root wall of the root canal 6 has been removed with a cutting instrument such as a reamer up to just before the apical foramen 8, which is the base of the root canal 6. It has been cut. The above-mentioned cutting tool also has a gripping part, a cutting part, and a stopper supported between the cutting part or the cutting part and the gripping part, and the stopper is arranged so as to come into contact with the distal end surface 5a of the tooth 5. It's summery.

In the above structure, the length of the uncut portion of the root canal 6 is measured using the dental root canal insertion instrument 1.

In advance, the stopper 4 of the dental root canal insertion instrument 1 is
Length A from stopper 4 to tip 3b of insertion section 3
is set so that it is the same length as the length from the stopper to the tip of the cutting part of the cutting tool such as the reamer used during cutting.

The insertion part 3 of the dental root canal insertion instrument 1 is inserted into the pulp chamber 7.
Then, the tooth is inserted into the root canal 6, and the stopper 4 is brought into contact with the distal end surface 5a of the tooth 5 and latched.

X-ray photography is performed in the above conditions. Then, since the insertion part 3 made of tungsten is extremely impermeable to X-rays compared to the conventional insertion part made of stainless steel, etc., the image of this insertion part 3 is shown on the X-ray film taken. It is shown very clearly.

Then, the distance B between the distal end 3b of the insertion portion 3 and the apical foramen 8 at the base of the root canal 6, which is imaged on the X-ray film, is measured. This interval B becomes the length of the uncut portion.

Therefore, by shifting the position of the stopper of the cutting instrument by dimension B from the position at the time of cutting and cutting again, the uncut portion of the root canal 6 can be reliably cut, and the tip of the cutting instrument can be aligned with the root. It does not protrude from the apex hole 8 and damage the periodontal tissue.

Note that the stopper 4 of the root canal insertion instrument 1 does not have to be set in correspondence with the stopper of the cutting instrument used for cutting as described above. In this case, the root canal insertion instrument 1 is taken out from the tooth 5, and the length A from the straight end 3b of the insertion section 3 to the stopper 4 is measured.
and the distance B between the tip 3b and the apical foramen 8 on the X-ray film. This interval B does not match the length of the uncut portion. From the above measurement results, A+B
From the stopper 4 of the root canal insertion instrument 1 to the apical hole 8
(This length is generally referred to as the total length of the root canal 6).

Therefore, by setting the stopper of the cutting tool so that the length from the stopper to the tip becomes A+B and cutting again, the uncut portion can be reliably cut.

Further, when the insertion portion 3 is inserted into the root canal 6, it is curved in a direction parallel to and perpendicular to the plane of the paper in FIG. 2 (X-ray film plane). The degree of curvature in the direction parallel to the X-ray film surface can be clearly determined from the X-ray film. On the other hand, the degree of curvature in the direction perpendicular to the X-ray film surface is determined by the length A' from the tip 3b of the insertion portion 3 shown on the X-ray film to the tip surface 5a of the tooth 5, and the length A' of the tip 3b in the straight state. This can be determined from the difference between the length A and the stopper 4.

Note that the insertion portion 3 does not necessarily require the tapered portion 3c, and may be formed straight across the entire length. Further, the shape of the tip 3b is not particularly limited to a hemispherical shape.

This invention is not limited to the above-mentioned embodiments, and various embodiments are possible. For example, the material of the insertion portion may be a tungsten alloy.

In addition, tungsten has high bending strength, heat resistance, and wear resistance, so dental root canal insertion instruments can be used with other dental instruments, such as cutting instruments (reamers, files, etc.), root canal exploration instruments. (smooth broach), pulp removal instrument (cleanser), etc.

Furthermore, it is also possible to apply the present invention to a root canal insertion instrument using an electrical method.

(Effects of the invention) As explained above, in this invention, by making the insertion part of the dental root canal insertion instrument made of tungsten, the image of the insertion part can be clearly shown on the X-ray film taken. This is advantageous when accurately measuring root canal length.

[Brief explanation of the drawing]

The drawings shown in FIGS. 1 and 2 show an embodiment of this invention, and FIG. 1 is a front view of a dental root canal insertion instrument, and FIG. 2 is a sectional view of a usage mode. 1... Dental root canal insertion instrument, 3... Insertion part, 5
...Tooth, 6...Root canal.

Claims (1)

[Scope of utility model registration request] A dental root canal insertion device inserted into a root canal of a tooth for X-ray photography, characterized in that the root canal insertion portion is made of tungsten.