JPH09276292A - Dental caries removing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove a carious dentine without damaging sound dentine by forming a dental caries removing material of an abrasive grain having a hardness equal to or lower than the sound dentine. SOLUTION: A dental caries removing material is sprayed to a carious dentine from the nozzle 1 of a sand blaster to remove a carious dentine 2. The dental caries removing material is formed of an abrasive grain having a hardness equal to or lower than a sound dentine, and the hardness is set to HV 7-200, particularly, HV 40-200. The grain size of the abrasive grain of the dental caries removing material is set to #20-#360, particularly #20-#120. Further, the abrasive grain of the dental caries removing material is made of an organic material or a composite material, and the organic material is made of a synthetic resin or vegetable fiber. The synthetic resin is made of melamine resin, urea resin, polycarbonate resin or acryl resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caries removing material capable of removing caries without damaging healthy tooth structure.

[0002]

2. Description of the Related Art Dental caries is a process in which dentin (composed of an inorganic component and an organic component) is decalcified and softened by an acid produced by bacteria, and the remaining organic components are decomposed by the bacteria to cause defects. Proceed by. Removal of caries is to remove extremely softened areas and areas where bacteria may invade and cause caries to recur unless removed.

Conventionally, in the treatment of caries, a healthy tooth substance including caries was ground to form a box shape so that the restoration could not fall off. In recent years, however, the restoration was developed due to the development of an adhesive resin material. Since it shows a strong adhesive force to the tooth substance, there is no need to remove the healthy tooth substance in the treatment of caries, and it is important to completely remove the dental caries and leave the healthy tooth substance to the maximum extent.

At present, as a means of knowing the range of caries, the hardness of caries, the natural coloring of caries, and the dyeing with a caries detecting liquid (this is the only reliable way to know the range of caries, because it stains only caries red. ) Is mainly used. When removing caries, first remove the softened caries, and then carefully remove the naturally colored parts caused by caries and the areas dyed by the caries detection solution so as not to damage the healthy tooth structure. Achieved by For caries removal, a steel round bar is mainly used for a micromotor which is a rotary grinding tool.

Incidentally, the hardness of caries is so soft that it cannot be measured by a Vickers hardness meter on the surface side, and the hardness suddenly increases at the boundary with healthy dentin, and shows a value of about HV25-40. On the other hand, the hardness of healthy dentin is HV40-6.
It is about 0.

[0006]

This caries removal work is performed in a narrow surgical field in the oral cavity, and depending on the site, the operator cannot directly see the caries, and can see the caries only by using a mirror. Therefore, depending on the skill of the surgeon, there is a risk of forgetting to take caries (causing reoccurrence of caries will cause recurrence of caries) and excessive cutting of healthy tooth structure. In addition, even a well-trained operator requires a long treatment time and labor.

Nowadays, there is a demand for a method of easily removing only caries without taking time, regardless of the skill of the operator. In the cutting using the rotary turbine such as an air turbine or a micromotor, both caries and healthy dentin are cut, so there is no other way than cutting by selecting only caries depending on the skill of the operator. Further, in the air blasting device using alumina as a grinding material which has started to be clinically used in recent years, it is considered difficult to use this device for the purpose of removing dental caries because a healthy tooth substance is more easily ground than dental caries. .

[0008] Therefore, at present, no method has been developed except for the fact that the surgeon pays close attention to remove only caries. Therefore, the present inventor has developed a method for selectively removing only caries without grinding healthy teeth by using abrasive particles having a hardness that does not grind healthy teeth as an abrasive for air blast. Then, the present invention has been completed.

The present invention has been made on the basis of such findings, and an object thereof is to provide a caries removing material capable of easily removing carious tooth without damaging healthy tooth. is there.

[0010]

The invention according to claim 1 is characterized by comprising abrasive particles having hardness equal to or lower than that of sound tooth.

A second aspect of the present invention is characterized in that the caries removing material according to the first aspect has a hardness of HV7 to 200. The invention of claim 3 is the caries-removing material according to claim 1, wherein the hardness is HV40 to 200. A fourth aspect of the invention is characterized in that the caries removing material according to the first aspect has a hardness of HV7-40.

A fifth aspect of the invention is characterized in that the caries removing material according to the first aspect has a hardness of HV7-30. The invention of claim 6 is the caries-removing material according to claim 1, wherein the abrasive particles have a particle size of # 20 to # 360. The invention of claim 7 is the caries-removing material according to claim 1, wherein the abrasive particles have a particle size of # 20 to # 120.

The invention of claim 8 is the caries-removing material according to claim 1, wherein the abrasive particles are made of an organic material or a composite material. The invention of claim 9 is the caries removing material according to claim 8, wherein the organic material is a synthetic resin or a vegetable fiber. According to a tenth aspect of the invention, in the caries removing material according to the ninth aspect, the synthetic resin is a melamine resin, a urea resin, a polycarbonate resin, or an acrylic resin.

The invention according to claim 11 is the caries-removing material according to claim 9, wherein the vegetable fibers are peach seed shells, apricot seed shells, walnut seed shells, corn cores, and plum seed shells. shell,
Characterized by pistachio seed shells, almond seed shells, ebony and rosewood. The invention of claim 12 is the caries removing material according to claim 8, wherein the composite material is a mixture of an inorganic material or a metal material and a synthetic resin, a mixture of a vegetable fiber and an inorganic material, and a mixture of a vegetable fiber and a synthetic resin. It is characterized by being a mixture.

(Operation) In the inventions of claims 1 to 12, the caries can be removed by, for example, injecting toward the caries from the nozzle of the sand blaster. Here, the hardness of the abrasive is HV7 to 200.
The hardness of this abrasive was measured with, for example, a Shimadzu Micro Vickers hardness meter HMV-2000. The measurement conditions were 15 g and a holding time of 5 seconds.

The abrasive is composed of an organic material or a composite material. As the organic material, synthetic resin and vegetable fiber are suitable. Examples of the synthetic resin include melamine resin, urea resin, polycarbonate resin, and acrylic resin. Vegetable fibers include peach seed shell, apricot seed shell, walnut seed shell, corn core, plum seed shell, pistachio seed shell, almond seed shell, ebony, rosewood, etc. There are high-strength vegetable fibers.

Examples of the composite material include a mixture of an inorganic material or a metal material and a synthetic resin, a mixture of a vegetable fiber, an inorganic material and a synthetic resin, and a mixture of a vegetable fiber and a synthetic resin. A mixture of inorganic material or metal material and synthetic resin,
It is a composite material of synthetic resin. This composite material, for example,
Melamine resin, urea resin, polycarbonate resin, acrylic resin, Bis-GMA (2,2-bis (p-2-hydroxy-3-me
Inorganic particles such as quartz glass, aluminosilicate glass, lithium aluminum silicate, borosilicate glass, synthetic apatite, silicon nitride, colloidal silicic acid, copper, silver, gold, platinum, etc., using synthetic resin such as thacryloxy propoxyphenyl) propane) as a substrate. Alternatively, it is a mixture of metal particles.

Further, the composite resin of the restorative material used in dentistry contains silicon glass filler in Bis-GM.
A (2,2-bis (p-2-hydroxy-3-methacryloxy propoxy phe
It is mixed in the organic matter of (nyl) propane).

This composite material is almost equivalent in hardness to dentin, and caries can be removed by using a synthetic resin composite material. In addition, the mixture of vegetable fiber and synthetic resin, peach seed shell, apricot seed shell, walnut seed shell, corn core, plum seed shell, pistachio seed shell, almond seed It is made by combining crushed particles of high-strength vegetable fibers such as husks, ebony, and rosewood with a synthetic resin.

Further, the mixture of vegetable fiber, inorganic material and synthetic resin can be used for peach seed shell, apricot seed shell, walnut seed shell, corn core, plum seed shell, pistachio seed. Shells, almond seed shells, high-strength vegetable fibers such as ebony, rosewood, quartz glass, aluminosilicate glass, lithium aluminum silicate, borosilicate glass, synthetic apatite, silicon nitride, colloidal silica, copper, silver, Inorganic particles or metal particles such as gold and platinum are bound by a synthetic resin.

Next, the hardness of the abrasive will be described. Comparing synthetic resin and hardness (HV), melamine resin (HV150-200), urea resin (HV150-20)
0), a polycarbonate resin (HV40 to 55), and an acrylic resin (HV50 to 60). Moreover, when these vegetable fibers and hardness (HV) are compared, peach seed shells (HV15-40), apricot seed shells (HV14-40),
Walnut seed shells (HV10-30), corn cores (HV7-20).

By the way, since the melamine resin and the urea resin have a hardness (HV) higher than that of sound dentin, the dentin is ground slightly, but when the caries are actually removed, the speed of grinding the caries is high. Compared with this, since the speed of grinding a healthy tooth substance is very slow, only caries is selectively ground. That is, for the selective removal of caries, it was thought that particles of the same level or less as those of healthy dentin were good, but with a hardness of about melamine resin and urea resin, since healthy teeth are not ground to such a degree that they become clinically problematic, particles Up to a hardness of about HV200, it is used as abrasive particles for the selective removal of caries.

Therefore, the hardness equivalent to that of the healthy tooth substance in the present invention is, as described in claims 2 and 3,
It refers to an HV of about 200, exceeding HV40 to 60. On the other hand, the hardness of peach seed shells and apricot seed shells is not so great, but when actually removing caries,
The caries are removed at a high speed, completely removing the part dyed with the caries detection liquid, and not grinding more healthy dentin, and because the material is a natural material, grinding for selective caries removal Useful as particles.

The hardness of these is HV as described in claim 4.
7 to 40. Further, the hardness of the composite material is almost the same as the hardness of dentin, and the caries can be removed also by using the inorganic / organic composite material. Also,
In the case of walnut seed shells and corn cores, it was not possible to completely remove the part stained with caries detection liquid, but clinically it is better not to completely caries (especially temporary indirect pulp capping). Law) is considered to have great utility value.

Here, the temporary indirect pulp capping method means that if the caries may reach the pulp if all the caries are removed by the first treatment, cement or the like is left for about 3 months after leaving more caries. It is a method of removing all caries by the second treatment when the pulp is set back and the tooth pulp recedes while adding dentin. The temporary indirect pulp capping method can remove caries without damaging the pulp. In Europe and the United States, it is routinely used as a means to protect the pulp when caries is deep. The pulp is a soft tissue inside the tooth and is generally called a nerve. If caries has been scraped and reaches the pulp, treatment to remove the pulp must be performed. Pulped teeth are considered to have a shorter lifespan than teeth with pulp, and treatment that leaves pulp is prioritized if possible.

Therefore, for this purpose, the hardness is set to HV7 to 30 as in claim 5. The particle size of the abrasive is # 20 to # 360. The grain size of this abrasive is
Measured with JIS mesh. For synthetic resins and vegetable fibers, it is not practical to make the particle size smaller than # 360 because it is difficult to process while maintaining the above-mentioned hardness, and when the particle size is larger than # 20, This is not preferable because it makes the patient feel uncomfortable during treatment and makes it difficult to use for caries removal.

From the above, in the present invention, any abrasive may be used as long as it has hardness equal to or lower than that of sound tooth, but it is used for treatment in the oral cavity. Therefore, it is desirable to be composed of an organic material or a composite material. Then, when the hardness equal to or lower than that of healthy teeth is displayed in HV hardness, H
V7-200, HV40-200 when the abrasive is a synthetic resin or a composite material thereof, HV7-40 when the abrasive is a vegetable fiber, and even a vegetable fiber In the case of relatively low hardness such as peach seed shell and apricot seed shell, the HV is 7 to 30.

Further, in the present invention, not only the hardness is used as a guide, but it is used for treatment in the oral cavity, and from the viewpoint of caries removal, the particle size is # 20 to.
# 360. Of course, in order to remove caries efficiently and completely, it is considered that not only HV hardness but also factors such as particle shape, size, density, and injection pressure need to be adjusted. Is material, hardness and particle size.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION

(Experiment 1) Alumina, glass beads, melamine resin, urea resin, polycarbonate resin, acrylic resin, peach seed shell, apricot seed shell, walnut seed shell, and corn core shown in Table 1 are shown in FIG. As shown in, the injection pressure is 4.5 at
m, distance between nozzle samples 2 mm, jetting time 3 seconds, nozzle diameter 0.8 mm (however, polycarbonate resin (TP
L), peach seed shell (PS), apricot seed shell (AP), walnut seed shell (KS), corn core (CC) 1.2 mm), spray angle 90 ° Quality, dentin, caries model (demineralized dentin) is ground,
The grinding depth was measured.

In FIG. 1, 1 is a sand raster nozzle, 2 is carious tooth, 3 is enamel, and 4 is dentin.

[Table 1] <Result 1> The results are shown in Table 2 and FIG.

With respect to alumina particles, the grinding amount was larger in enamel and dentin than in the caries model in all particle sizes from # 700 to # 80. # 3 for glass beads
The caries model was ground more than enamel and dentin in all grain sizes from 60 to # 80. With the melamine resin (TPS) # 80 and the urea resin (TPU) # 80, the grinding depth of the enamel was less than the measured value, and the dentin was slightly ground, and many caries models were ground.

Polycarbonate resin (TPL) # 80,
Polycarbonate resin (TPL) # 60, acrylic resin (TPC) # 80, peach seed shell (PS) # 60, apricot seed shell (AP) # 60, walnut seed shell (KS) # 60,
With corn core (CC) # 60, the grinding depth of enamel and dentin was less than the measured value, and only the caries model was ground.

[Table 2] (Experiment 2) Using # 100 alumina and # 100 glass beads, the injection pressure condition was changed in the range of 2.0 to 4.5 atm, and the other conditions were the same as those of Experiment 1, and the grinding depth was measured and the injection was performed. The relationship between pressure and grinding depth was investigated. <Result 2> The results are shown in FIGS. 3 and 4.

At all injection pressures, it was revealed that with alumina, enamel and dentin were easier to grind than with a caries model, and with glass beads, a caries model was easier to grind than with enamel and dentin. . [Discussion b] Grinding efficiency is increased by increasing the particle size and injection pressure as compared with Experiments 1 and 2, but with each particle size and each injection pressure, there are more healthy teeth than caries in caries. Grinding, caries carved more than healthy teeth with glass beads. In other words, it has been clarified that, with alumina and glass beads, the sound tooth substance is ground even if the particle size and the injection pressure are changed.

Melamine resin (TPS), urea resin (TP
In U), although the sound tooth substance was slightly ground, compared with that, more caries was ground. Polycarbonate resin (T
PL), acrylic resin (TPC), peach seed shell (P
S), apricot seed shell (AP), walnut seed shell (KS),
It was found that corn core (CC) grinds only healthy caries and not caries.

From the above, it has been found that in order to selectively grind only caries, the characteristics of the grinding particles themselves are more important than the particle size and the injection pressure of the air blasting device. Looking at Table 1, alumina (HV2000-30
00), glass beads (HV500 to 550), melamine resin (TPS) (HV150 to 200), urea resin (TPU) (HV150 to 200) are healthy dentin (H
Hardness is higher than that of V40-60), polycarbonate resin (TPL) (HV40-55), acrylic resin (TPC) (HV50-60), peach seed shell (PS)
(HV15-40), apricot seed shell (AP) (HV14-
40), walnut seed shell (KS) (HV10-30),
Corn cores (CC) (HV7-20) had less hardness than healthy dentin.

From this, it was found that the hardness of the particles needs to be equal to or less than the hardness of the dentin in order to grind only the caries without grinding the healthy dentin. (Experiment 3) Using the particles used in Experiment 1, as shown in FIG. 1, an injection pressure of 4.5 atm, a nozzle diameter of 0.8 mm (however, polycarbonate resin (TPL), peach seed shell (P
S), apricot seed shell (AP), walnut seed shell (KS),
The caries of the extracted human tooth were actually removed under the condition of corn core (CC) of 1.2 mm).

<Result 3> In the case of alumina, the caries can be easily removed if the particle size is large to some extent, but the removal time becomes long if the particle size is small. Moreover, irrespective of the size of the particles, the healthy dentin was also ground beyond the caries. With glass beads, it took a long time to remove caries even with large particles. Moreover, regardless of the size of the particles, they also grinded healthy dentin beyond caries.

Melamine resin (TPS), urea resin (TP
In U), the site stained with the caries detection liquid could be completely removed in about 30 seconds. Although it seemed that the healthy dentin was removed over a longer period of time, the speed was much slower than the removal of caries, and clinically using these particles seems to be no problem. It was With the polycarbonate resin (TPL) # 80, the site dyed with the caries detection liquid could be removed in about 40 to 50 seconds, but even if the resin was sprayed further, one layer dyed with the caries detection liquid remained.

With the polycarbonate resin (TPL) # 60, the portion stained with the caries detection liquid was completely removed in about 30 seconds, and even if the injection was continued, a healthy tooth structure was not ground. Peach seed shell (PS), apricot seed shell (AP)
Then, in about 30 seconds, the part stained with the caries detection liquid was completely removed, and even if the injection was continued, the healthy tooth structure was not ground.

With the walnut seed shell (KS), it was possible to remove the part that was almost stained with the caries detection liquid in about 40 seconds, but even if it was sprayed further, it was dyed with the caries detection liquid (0.2 m
m) is left. In the corn core (CC), a portion (0.7 mm) stained with the caries detection liquid was left more than in the walnut seed shell (KS), and the grinding was impossible.

[Discussion B] As presumed in Experiments 1 and 2, it is difficult to use these particles for the purpose of selectively removing caries by grinding even healthy dentin with alumina and glass beads. . In Experiment 1, melamine resin (TPS) and urea resin (TPU) slightly grind dentine. However, when caries were actually removed, the speed of grinding healthy dentin was higher than that of caries. It was so slow that I felt that only caries were selectively ground.

In consideration (a), it was thought that particles having the same level or less as those of healthy dentin are suitable for the selective removal of caries, but with a hardness of about melamine resin (TPS) and urea resin (TPU), there is a clinical problem. Since it does not grind the sound tooth substance to such an extent, it is considered that the particles are used as grinding particles for selective removal of caries up to a hardness of HV200. Polycarbonate resin (TPL) # 80 and polycarbonate resin (TP
L) # 60, polycarbonate resin (TP
L) In # 60, the area that was almost completely dyed with caries detection liquid was deleted, but polycarbonate resin (TPL) # 80
Then I was left with some caries. Polycarbonate resin (TPL) # 80 and polycarbonate resin (TPL) #
60 is made of the same material, but as shown in the SEM images shown in FIGS. 5 and 6, polycarbonate resin (TP
L) # 80 is polycarbonate resin (TPL) # 60
It is thought that the grinding force was smaller because the cracks were inside the particles and the contours were slightly rounded compared to.

From this, it can be seen that even particles made of the same material can have a slight difference in grinding force depending on the method of manufacturing the particles. Peach seed shell (PS), apricot seed shell (A
The hardness of P) is not so large, but when caries are actually removed, the speed of caries removal is fast, and the part stained with caries detection liquid is completely removed, and more healthy dentin is ground. Since it was not used and the material was a natural material, it was considered to be useful as abrasive particles for selective caries removal.

With the shell of walnut seeds (KS) and the core of corn (CC), it was not possible to completely remove the part stained with the caries detection liquid, but clinically it is better not to completely caries. In this case (especially the temporary indirect pulp capping method), it is considered to have great utility value. There is a difference in whether or not particles made of the same material can completely remove caries, and peach seed shell (PS), which has a lower degree than polycarbonate resin (TPL), can effectively remove caries. Walnut seed shell (AP; average hardness is HV20.8) having an average hardness higher than that of the walnut seed shell (KS; average hardness HV2)
Since caries could be completely removed compared to 2.4), it can be seen that the grinding force for caries cannot be determined only by the hardness (HV hardness).

However, what is most important for selectively grinding only caries is particles having an HV hardness of about 7 to 200, or plant fibers having a high degree, or processed products thereof, or synthetic resins, Or it is to select the processed product, and to remove caries completely more efficiently,
It is considered necessary to adjust not only HV hardness but also factors such as particle shape, size, density, and injection pressure.

Next, the removal of caries by peach seed shell (PS) # 60 will be further described. FIG. 7 shows a cross section of a human extraction tooth in which caries are dyed red with a caries detection liquid. In the figure, 5 is a caries portion in which caries is detected by a caries detection liquid.

FIG. 8 shows that peach seed shell (PS) # 60 was air-blasted for about 20 seconds at an injection pressure of 4.5 atm, a nozzle sample distance of 2 mm and a nozzle diameter of 1.2 mm, and then dyed again with a caries detection liquid. Figure 3 shows a cross section of a human extracted tooth. As is clear from FIG. 8, the carious portion 5 was completely removed, but the healthy dentin 6 therebelow was not removed. A part 7 that is stained a little red is recognized in the enamel 8, but this is the caries detection liquid remaining on the irregularities of the enamel 8 after the caries are removed, and is not the remaining caries. That is, in FIG. 8, only the caries carved out in FIG. 7 is completely removed, and healthy tooth structure is not ground.

Next, for the tooth shown in FIG. 7, alumina # 1 was used.
00 is an injection pressure of 4.5 atm, the distance between nozzle samples is 2 m
m, nozzle diameter 1.2 mm, air blasting for about 20 seconds, and then the cross section of the extracted human tooth again stained with caries detection liquid.
Shown in As is clear from FIG. 9, alumina has a very high grinding force, and the carious portion 5, dentin 6 and enamel 8 have been removed. That is, in FIG. 9, sound dentin was also ground beyond caries, and perforated into the pulp cavity.

From these results, it can be seen that it is impossible to selectively remove caries by air blasting using alumina. (Experiment 4) Under the same conditions as in Experiment 3, the air blast was mixed with water (wet blasting) and injection was performed.

<Result 4> It seems that the grinding efficiency is lowered as a whole. With alumina and glass beads, healthy dentin was ground. Melamine resin (TPS), urea resin (TPU), carbonate resin (TPL), acrylic resin (TPC), peach seed shell (PS), apricot seed shell (A
In P), the part stained with the caries detection liquid was completely removed, and the healthy dentin was scarcely ground.

With walnut seed shells (KS) and corn cores (CC), it was not possible to completely remove the part stained with the caries detection liquid. [Conclusion] In order to grind carious dentin without grinding healthy dentin, it was found that it is necessary to dry or wet blast particles having a hardness of about HV7 to 200.

Further, among the particles of HV7 to 200, those having a high hardness can grind a little sound tooth substance, and therefore can be used when grinding the sound tooth substance as well. Further, if the hardness is low, it can be used for the purpose of not completely removing caries or for the first rough caries removal at the time of caries removal.

[0053]

As described above, the claims 1 to 1 are as follows.
According to the second aspect, the carious tooth substance can be easily removed without damaging the healthy tooth substance.

In particular, when the abrasive is a vegetable fiber, it has less discomfort than an abrasive made of synthetic resin and is suitable for use in the oral cavity.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of use of a carious abrasive according to the present invention.

FIG. 2 is a diagram showing a relationship between each particle and a grinding depth.

FIG. 3 is a diagram showing a relationship between an injection pressure and a grinding depth.

FIG. 4 is a diagram showing a relationship between an injection pressure and a grinding depth.

FIG. 5: SE of polycarbonate resin (TPL) # 80
It is a figure by M observation.

FIG. 6 SE of polycarbonate resin (TPL) # 60
It is a figure by M observation.

FIG. 7 is a sectional view of a human extraction tooth in which caries are dyed red with a caries detection liquid.

8 is a peach seed shell (PS) # 6 for the extracted tooth of FIG.
FIG. 3 is a cross-sectional view of a human extraction tooth that was air-blasted with 0 at a pressure of 4.5 atm for about 20 seconds and then again stained with a caries detection liquid.

FIG. 9 is a cross-sectional view of the extracted external tooth of FIG. 7 in which alumina # 100 was air-blasted at a pressure of 4.5 atm for about 20 seconds and then again stained with a caries detection liquid.

[Explanation of symbols]

1 Sandra star nozzle 2 Dental caries 3 Enamel 4 Dentin 5 Dental caries part dyed red by caries detection solution 6 Dentin 7 Part cartilage detection liquid left on unevenness of enamel 8 Enamel quality

[Procedure amendment]

[Submission date] April 22, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of use of a carious abrasive according to the present invention.

FIG. 2 is a diagram showing a relationship between each particle and a grinding depth.

FIG. 3 is a diagram showing a relationship between an injection pressure and a grinding depth.

FIG. 4 is a diagram showing a relationship between an injection pressure and a grinding depth.

FIG. 5: SE of polycarbonate resin (TPL) # 80
It is a photograph by M observation.

FIG. 6 SE of polycarbonate resin (TPL) # 60
It is a photograph by M observation.

FIG. 7 is a halftone image in which a cross section of a human extraction tooth in which caries is dyed red with a caries detection liquid is displayed on a display .

8 is a peach seed shell (PS) # 6 for the extracted tooth of FIG.
After air blasting 0 for about 20 seconds at a pressure of 4.5 atm, the cross section of the extracted human tooth that had been dyed again with the caries detection liquid was cut.
It is a halftone image displayed on the spray .

FIG. 9: Alumina # 100 was air blasted for about 20 seconds at a pressure of 4.5 atm on the extraction tooth of FIG. 7, and then the cross section of the extraction tooth dyed again with a caries detection liquid was displayed.
It is a halftone image displayed in FIG.

[Explanation of symbols] 1 Nozzle of sand star 2 Caries tooth 3 Enamel 4 Dentin 5 Dental caries part dyed red with caries detection liquid 6 Dentin 7 Caries detection liquid left on unevenness of enamel slightly stained red Part 8 Enamel

Claims (12)

[Claims] 1. A caries removing material comprising abrasive particles having a hardness equal to or lower than that of healthy teeth. 2. The caries removing material according to claim 1, wherein the hardness is HV7 to 200. 3. The caries removing material according to claim 1, wherein the hardness is HV40 to 200. 4. The caries removing material according to claim 1, wherein the hardness is HV7-40. 5. The caries removing material according to claim 1, wherein the hardness is HV7-30. 6. The caries removing material according to claim 1, wherein the abrasive particles have a particle size of # 20 to # 360. 7. The caries removing material according to claim 1, wherein the abrasive particles have a particle size of # 20 to # 120. 8. The caries removing material according to claim 1, wherein the abrasive particles are made of an organic material or a composite material. 9. The caries removing material according to claim 8, wherein the organic material is a synthetic resin or a vegetable fiber. 10. The caries removing material according to claim 9,
A caries removing material, wherein the synthetic resin is melamine resin, urea resin, polycarbonate resin, or acrylic resin. 11. The caries removing material according to claim 9,
The plant fiber is peach seed shell, apricot seed shell, walnut seed shell, corn core, plum seed shell, pistachio seed shell, almond seed shell, ebony, rosewood Caries removal material characterized by 12. The caries removing material according to claim 8, wherein
A caries removing material, wherein the composite material is a mixture of an inorganic material or a metal material and a synthetic resin, a mixture of a vegetable fiber and an inorganic material, and a mixture of a vegetable fiber and a synthetic resin.