BE1003526A4 - ODONTOTHERAPEUTIC MATERIALS. - Google Patents

Abstract

Odontotherapeutic material, based on two liquids A and B, containing materials which can form precipitates difficult to dissolve, and this immediately by mixing, liquid A being made up of an aqueous solution containing 1 to 70% of one or more salts of sodium, potassium and lithium of inorganic or organic acids, while liquid B consists of an aqueous solution containing 1 to 70% of one or more chlorides, nitrates, sulfates and acetates of various metals.

Description

"Odontotherapeutic materials"

The present invention relates to lemitive agents, preparative agents and obturating agents which are used in odontotherapy and it relates more particularly to lenitive agents for hypersensitivity, to preparative agents for coating and filling materials for the root canals.

Among dental stimuli, there is hypersensitivity and pulpalgia which are considered clinically as raising serious problems.

Hypersensitivity is caused, for example when living teeth are brought into a sensosthemic state by exposure of their dentin and come into physical or chemical contact with cold or sweet and sour foods and drinks, frozen products, galvanic current, a toothbrush, toothpick, etc., causing induced pain and severe pain, although they are transient or fleeting.

Brännström's hydrodynamic theory of the mechanism of hypersensitivity teaches that an external stimulus applied to the surface of the dentin causes tissue or pulp fluid to move in the dentinal tubules inward and outward. and thus stimulates the dentinal nerves of the pulp causing pain.

Although various other theories have also been suggested with regard to the mechanism of hypersensitivity, this has, however, been treated so far by various therapies as highlighted below.

(1) Mechanical protection of the surfaces of exposed dentinal tubules against stimuli of external origin. To this end, a "Hyperband" product containing paraformaldehyde is applied to these surfaces.

(2) Protection of the dentinal tubules against stimuli of external origin by promoting their internal calcification for their closure. To this end, the dentinal tubules are coated with a "Saforide" product containing a diamine-silver fluoride solution, or a "F vanish" product containing sodium fluoride - Therapy (2-1). Alternatively, the principle of iontophoresis is applied to feed an ionized drug in solution, deep into the affected area using a current - Therapy -2-2).

(3) A silver nitrate solution is applied to the odontoblasts to modify and coagulate them, thus preventing them from reacting with stimuli of external origin.

(4) Irradiation by laser beams.

These therapies (1) - (4) have been found to be ineffective for patients suffering from hypersensitivity, these therapies having the following shortcomings.

For example, coating with the product "Hyperband" containing paraformaldehyde to protect the surfaces of the exposed dentinal tubules, mechanically against external stimuli - Therapy (1) - involves a lot of work, because the components formed by a powder and a liquid must be mixed and kneaded together for their use, and one is thus limited in time because a period reaching 5 to 6 hours is necessary for the complete setting of the mixture of powder / liquid . In addition, the effectiveness of this therapy (1) generally reaches only 50%.

Therapy (2), according to which the product "Saforide" containing a solution of diamine-silver fluoride or the product "F vanish" containing a sodium fluoride is applied to the dentinal tubules to promote their internal calcification with a view to their shut off and thus protect them against stimuli of external origin, darkens the affected coated area and is therefore not desirable from an aesthetic point of view, being unsuitable for adults. In addition, the effectiveness of Therapy (2-1) generally reaches only 47%. The problems encountered with Therapy (2-2) or iontophoresis therapy, in which the principle of electrophoresis is applied to supply an ionized drug in a solution, and this deeply into the affected part using a current, is that 'it is necessary to have an expensive ion supply device; this therapy involves a lot of work; it causes fear in the patient; etc. In addition, Therapy (2-2) is not suitable since its effectiveness is generally only 40%.

Therapy (3), in which the odontoblasts are modified and coagulated by coating with a silver nitrate solution to prevent them from reacting to stimuli of external origin, makes the coated area blackish-brown in color, and therefore it is not desirable from an aesthetic point of view and is not suitable for adults. In addition, it generally shows an efficiency which reaches at most 50%.

Laser beam irradiation therapy (4), in which these laser beams are applied to the dentine surface of the affected part for about one minute is effective but requires an expensive laser irradiation device. In addition, this Therapy (4) shows an efficiency of 80% in some cases, but it is not as good in other cases.

The therapies used so far to treat hypersensitivity not only involve long and arduous work but may also require a special installation. Even without that, they involve considerable expenditure. From the patient's point of view, on the other hand, the problem is that the coated area becomes black and is therefore not desirable from an aesthetic point of view. Another problem is that, due to the lack of a lasting effect, the affected area must be coated periodically. Clinicians therefore still need to find a completely effective therapy when many people suffer from hypersensitivity.

On the other hand, the pulpalgia is caused by physical or chemical factors, such as the preparation of a cavity, the preparation of a tooth for a fixed prosthodontic appliance, obturation by resin, traumatic occlusion, changes in atmospheric pressure, fatigue, and food particles, and it causes pain ranging from throbbing and throbbing pain, acute, to mild pain. Pulpalgia is generally considered to be caused by reasons similar to those which have been mentioned concerning hypersensitivity, but it is still far from being elucidated from a pathogenic point of view, as is the case for hypersensitivity.

Consequently, pulpalgia has so far been treated using coatings, for example calcium hydroxide preparations, zinc oxide-eugenol cements, glass ionomer cements, carboxylate cements, etc. These cements are designed to be applied mechanically to the surfaces of the dentinal tubules to protect them from external stimuli.

The problems encountered with calcium hydroxide preparations are that these preparations are never hardened, that they are unable to give x-rays, that they are of poor strength, etc. Zinc oxide-eugenol cements consist of powders and liquid components which must be mixed and kneaded together for use. Since the liquid / powder ratio has to be around 0.5 and a large amount of the powder component has to be incorporated into the liquid component, mixing and kneading mostly involve a lot of work. In addition, this cement cannot be used in cases where a composite resin must be placed, because the liquid or eugenol component harms the polymerization of this resin. Zinc oxide-eugenol cements also raise resistance issues, etc.

The cements of glass ionomers and of carboxylate consist in each case of powders and liquid components which must be mixed and kneaded together for their use. The mixture is again tedious. As the liquid has a pH of 1.2 to 1.7, the mixture causes prolonged pain in the patient during the filling. As the cement film is subject to increase in thickness, there is a corresponding decrease in the thickness of a composite resin, which implies an aesthetic problem, etc.

The handling problems in the case of the therapies used until now to treat pulpalgia are that the mixing and kneading are tedious, that the cement film is subject to increasing in thickness, etc. From the patient's point of view, the problems are that these therapies cause prolonged pain during placement; it is not possible to achieve an aesthetic match of colors, etc.

Clinicians therefore still have to find a completely effective therapy or an effective lenitive agent (or preparative agent) for pulpalgia while many people suffer from it.

Various root canal blocking agents have been used to block a passage from the oral cavity to the vicinity of the root apex by blocking the formed and cleaned root canal and the apical foramen, or by promoting the growth and calcification of the connective tissue surrounding the apex of the root. By way of example, gutta-percha tips, silver tips, calcium hydroxide preparations, iodoform preparations, formaldehyde preparations and sealing agents of the oxide type have been used. zinc-eugenol.

(1) Gütta-percha tips.

This material has an appropriate plasticity.

It provides a high filling capacity and is stable, but it is difficult to find its way through the thin and sinuous root canals.

(2) Silver spikes.

This material is so fine and so rich in elasticity that it is suitable for filling the sinuous root canals, but it is so difficult to remove and so prone to corrosion that it can cause disturbances in the tissues.

(3) Preparation of calcium hydroxide.

The problems encountered with this preparation which is a pasty material designed mainly to promote the healing of bone lesions and the formation of hard tissue, are that this preparation never sets, that it lacks air tightness, that it is incapable of being x-rayed, that it does not suppose any antiseptic action, etc.

(4) Preparation of iodoform.

This material is less harmful to the tissues, capable of radiography and antiseptic, but it has the defect that it never takes when it is put in place.

(5) Preparation of formaldehyde.

This material shows antiseptic and disinfectant actions, but it is very prone to put the periodontium of the apex of the root in the sick state when this material is expelled.

(6) Sealant based on zinc oxide-eugenol.

This material shows lenitive and antiseptic actions with an increased sealing capacity, but it is irritating for the periodontium of the tip of the root and it is subject to contraction.

It is mentioned below what lenitive agents for hypersensitivity should present: (1) such an agent should be non-stimulating for dental pulp and gum, and minimize or eliminate any pain caused; (2) it should not cause tooth damage; (3) it should not cause discoloration of the teeth; (4) it should produce its effect through a simple action; (5) it should have an immediate effect; (6) it should maintain its effect; (7) it should not cause pain to the patient during or after treatment; and (8) it should not have to be distributed by any special device or equipment.

It is mentioned below that the remedies for pulpalgia (preparatory coating agents) should present: (1) such a remedy should be non-stimulating for dental pulp and gum and minimize or eliminate any pain caused; (2) it should not cause dentine damage; (3) it should not cause discoloration of the dentin; (4) it should ensure its effect through simple work; (5) it should have an immediate effect; (6) it should retain its effect; (7) it should not cause pain in the patient during or after treatment; (8) it should not require any special apparatus or equipment; and (9) it should not prevent polymerization of the resin.

Table I below shows how effective traditional therapies are against hypersensitivity and pulpalgia.

Table 1

O: Satisfactory (1) ~ (9): See above

Less satisfactory X; Not satisfying

As can be understood by considering Table I, traditional therapies for hypersensitivity not only raise problems in the sense that, by way of example only, they are irritating to the dental pulp and cause discoloration of the gum and of dentin, but that in addition they are disadvantageous, in the sense that, by way of examples only, they make the work of mixing and kneading tedious, and that their effect is neither reliable nor lasting. Furthermore, traditional therapies for pulpalgia not only pose problems in the sense that, by way of example only, they are irritating to the dental pulp and give rise to discoloration of the gum and dentin, but that moreover, they are disadvantageous in the sense that, by way of examples only, they exclude sealing by resin.

An object of the present invention is therefore to provide an odontotherapeutic material which can successfully satisfy what is both necessary for the treatment of hypersensitivity and what is necessary for the treatment of pulpalgia.

It is mentioned below what a root canal filling agent should have: (1) this agent should have good biocompatibility with a living body; (2) it should be non-stimulating and not harmful to the part of the periodontium surrounding the apical foramen; (3) it should be non-porous; (4) it should not cause discoloration of the dentin; (5) it should not undergo any change in its quality; (6) it should be removable if necessary; (7) it should be opaque to radiation; and (8) it should be easy to handle.

Among the sealants commonly available for root canals, there is a sealant that can close the apical foramen of the root canal, which is essentially necessary for good biocompatibility. To this end, a tip of gutta-percha is currently mainly used. However, even with a size available on the market for root canal, it is almost impossible to accurately measure the size of the root apex in the root canal. A problem encountered with the tip of gutta-percha is that, when it is effectively loaded under pressure into the root canal, it pierces the apex of the root or else it does not seal well.

According to what Brännström's theory of hydraulic dynamics teaches about why hypersensitivity occurs, external irritation applied to the surface of the dentin causes tissue or pulp fluid to flow through the dentin tubules and to thereby give rise to a variation in their internal pressure, irritating the dentinal nerve fibers to the point of causing pain. Therefore, one solution to solve the problems associated with traditional therapies concerning hypersensitivity and pulpalgia, while satisfactorily meeting the requirements for treating them, consists in controlling the movement of fluid in the dentinal tubules. On the basis of the results of various studies carried out for this purpose, it has been found that it is desirable to close the dentinal tubules with a material which is difficult to dissolve in water and which is non-stimulating. It was also noted that such a material should seal the long dentinal tubules.

Because of the above, the inventors have carried out extensive and long studies to find a material which can seal the long dentinal tubules and is very safe in use, which led to the finding of an odontotherapeutic material according to the present invention.

Accordingly, the present invention provides a two-pack system, consisting of liquids A and B designed to be applied in succession to the affected part where they can react with each other to form a substance which is difficult to dissolve in the 'water. This substance can then be used to seal long dentinal tubules or the apex of the root in the root canal.

More specifically, liquid A is mainly an aqueous solution containing 1 to 70% of one or more sodium, potassium and lithium salts of inorganic or organic acids, while liquid B is mainly an aqueous solution containing 1 to 70% of one or more chlorides, nitrates, sulfates and acetates of calcium, zinc, strontium, magnesium, aluminum, barium, iron, copper, silver, lead and tin.

For their use, liquids A and B are mixed together.

The substances used for liquid A in the form of a 1-70% aqueous solution may consist of one or more sodium, potassium and lithium salts of phosphoric acid, pyrophosphoric acid, tripolyphosphoric acid , metaphosphoric acid, polyphosphoric acid, phosphonic acid, phosphinic acid, sulfuric acid, sulfurous acid, carbonic acid, hydrogen fluoride, hydrogen sulfide and silicic acid or of members comprising, as acid groups, carboxyl, phosphoric, thiophosphoric, pyrophosphoric, phosphonic, phosphinic and sulfonic groups, all of which are soluble in water. Part of the water can be substituted with an alcohol, acetone, dimethyl sulfoxide, etc. Mention may especially be made of trisodium phosphate, disodium phosphate, monosodium phosphate, sodium pyrophosphate, sodium acid pyrophosphate, sodium tripolyphosphate, sodium metaphosphate, sodium phosphate, sodium phosphite, sodium sulfate sodium, sodium sulfite, sodium carbonate, sodium fluoride, sodium sulfide, sodium silicate, sodium benzoate, sodium salicylate, sodium oxalate, sodium malate, malonate sodium, sodium citrate, sodium succinate, sodium gluconate, sodium acrylate, sodium methacrylate, sodium vinyl benzoate, sodium styrene sulfonate, sodium phthalate and sodium trimellitate , as well as polymers or copolymers of sodium acrylate, sodium methacrylate or sodium maleate. It is also possible to use substances represented by the following chemical formulas I to III or their equivalents.

Of course, the potassium and lithium salts of the above substances can also be used.

I.

II.

III.

(R denotes 1 to 9 below)

The substances used for liquid B in the form of an aqueous solution at 1-70% may consist of one or more of the chorides, nitrates, sulfates and acetates of calcium, zinc, strontium, magnesium, aluminum , barium, iron, copper, silver, lead or tin, all being water soluble. Part of the water can be replaced by alcohol, acetone, dimethyl sulfoxide, etc. Special mention may be made of calcium chloride, zinc chloride, strontium chloride, magnesium chloride, aluminum chloride, iron chloride, copper chloride, barium chloride, tin chloride , zinc sulfate, strontium sulfate, magnesium sulfate, aluminum sulfate, copper sulfate, calcium nitrate, zinc nitrate, strontium nitrate, magnesium nitrate, nitrate d , iron nitrate, copper nitrate, silver nitrate, barium nitrate, lead nitrate, barium acetate, calcium acetate, strontium acetate, acetate magnesium, zinc acetate, lead acetate, etc.

Although this is generally not determinable, the substances can represent 1 to 70% of liquid A or liquid B. However, the substances should preferably represent 3 to 30% of liquid A or B for the treatment of hypersensitivity and pulpalgia. At a concentration of less than 1%, the reaction product is less precipitated and the application should therefore be repeated three to four times to close the root canal. At a concentration above 70%, on the other hand, it takes a long time to dissolve the component in water, which makes the work tedious. A range of concentrations which gives an effect in a given operation, allows this effect to be maintained and makes the dissolving work easy, is therefore considered to range from 3 to 30%.

The substances should preferably represent 10 to 60% of a treatment material for filling the apex of the root in the root canal. At a concentration below 10%, the reaction product is so slightly precipitated that the root apex cannot be completely closed, while at a concentration above 60%, it takes a long time to dissolve the component in water, which makes the job tedious. A range of concentrations which allows the obturation of the apex of the root in the root canal during an operation and makes the dissolving work easy, is therefore considered to range from 10 to 60%.

Liquids A and / or B may contain, in addition to water and the essential component, a monomer component comprising one or more hydrophilic groups, such as hydroxyl, carboxy and sulfone groups, and at the same time a polymerizable double bond. Mention may be made, for example, by way of illustration, of 2-hydroxy-ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxy-propyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, methacrylic acid, acrylic acid, 2-acrylamide-2-methylpropanesulfone, N-vinylpyrrolidone, polyethylene glycol di (meth) acrylate and mixtures thereof. The concentrations of these monomers in water are preferably of the order of 5 to 80%.

The manner of using the odontotherapeutic material according to the present invention will be explained below.

For hypersensitivity: (1) the affected area is cleaned and dried; (2) liquid A is applied to the affected area from a dental plaque with a sponge; (3) liquid B is applied to the layer of liquid A from another dental plaque with a sponge; and (4) the excess liquid deposited on the affected parts and others is removed by a cotton ball.

The order of application of liquids A and B can be reversed.

For the treatment of pulpalgia (with a preparative coating agent): (1) a cavity cleaning agent, marketed by GC Dental Industrial Corp., under the name "GC Dentine Conditioner", is applied to the affected area to remove the layers of stains that have been formed by the mechanical cutting of dentin; (2) the affected area is cleaned and dried; (3) liquid A is applied to the affected area with a sponge; (4) liquid B is applied to the layer of liquid A with a sponge; (5) the excess liquid deposited on the affected parts and others is removed by a cotton ball; and (6) a dental bonding material is applied to the resulting layers to secure.

The order of application of liquids A and B can be reversed.

For obturation of the root apex in the root canal: (1) the root canal is enlarged by a reamer, a file, etc., and this root canal is well cleaned internally; (2) the root canal is again cleaned internally by liquid A, using a dental syringe; and (3) fluid B is forced through the apex of the root into the root canal using a syringe again.

The order of application of liquids A and B can be reversed.

Examples

The odontotherapeutic materials according to the present invention will be explained more fully below by way of illustration but without limitation, and this with reference to the Examples presented. The components forming the odontotherapeutic materials are presented by Examples 1-34.

Example 1

A 5% aqueous solution of disodium phosphate was prepared as liquid Al, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Next, a 10% aqueous solution of calcium chloride was prepared as liquid B1, which was then adjusted to pH 7.4 with a 5% solution of hydrochloric acid.

The affected area of a patient with hypersensitivity was cleaned and dried, and Al fluid was applied to it with a tampon. Then, liquid B1 was applied to the liquid layer A1 using a sponge. The pain was immediately removed in the patient.

Examples 2-22

The procedures of Example 1 were followed except that the liquids A2-22 and B2-22 were used. The results are the same as those described for Example 1.

Example 2

Liquid A2 - Mixed liquid of a 5% aqueous solution of disodium phosphate with a 2% aqueous solution of sodium fluoride, which has been adjusted to pH 7.2 with an aqueous solution of 5% monosodium phosphate .

Liquid B2 - 10% aqueous solution of calcium chloride, which has been adjusted to pH 7.2 with a 5% aqueous solution of hydrochloric acid.

Example 3

Liquid A3 - A 10% aqueous solution of trisodium phosphate which has been adjusted to pH 7.0 with a 10% aqueous solution of monosodium phosphate.

Liquid B3 - 20% aqueous solution of zinc chloride, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium hydroxide.

Example 4

Liquid M - 10% aqueous solution of trisodium phosphate, which has been adjusted to pH 7.0 with a 10% aqueous solution of sodium sulfate.

Liquid B4 · - 20% solution of strontium chloride, which has been adjusted to pH 7.0 with a 1% aqueous solution of sodium hydroxide.

Example 5

Liquid A5 - 5% aqueous solution of disodium phosphate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B5 - 20% aqueous solution of zinc chloride, which has been adjusted to pH 7.0 with a 5% solution of sodium hydroxide.

Example 6

Liquid A6 - 5% aqueous solution of disodium phosphate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B6 - 20% aqueous solution of strontium chloride, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium hydroxide.

Example 7

Liquid A7 - 5% aqueous solution of sodium pyrophosphate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B7 - 15% aqueous solution of calcium chloride, which was added at pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 8

Liquid A8 - 5% aqueous solution of sodium pyrophosphate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B8 - 10% aqueous solution of zinc chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium hydroxide.

Example 9

Liquid A9 - 5% solution of sodium pyrophosphate, which was adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B9 - 20% aqueous solution of strontium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium hydroxide.

Example 10

Liquid A10 - 10% aqueous solution of sodium maionate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B10 - 10% aqueous solution of zinc chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium hydroxide.

Example 11

Garlic Liquid - 5% aqueous solution of sodium salicylate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid Bll - 20% aqueous solution of zinc chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium hydroxide.

Example 12

Liquid A12 - Mixed liquid formed from a 5% aqueous solution of disodium phosphate with a 5% aqueous solution of sodium pyrophosphate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B12 - 20% aqueous solution of zinc chloride, which has been adjusted to pH 7.0 with an aqueous solution of 5% sodium hydroxide.

Example 13

Liquid Al3 - Mixed liquid formed from a 5% aqueous solution of disodium phosphate with a 5% aqueous solution of sodium polyacrylate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B13 - 20% aqueous solution of calcium chloride, which has been adjusted to pH 7.0 with a 5% solution of hydrochloric acid.

Example 14

Liquid Al4 - Mixed liquid formed from a 5% aqueous solution of disodium phosphate with a 5% aqueous solution of sodium polyacrylate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B14 - 20% aqueous solution of zinc chloride, which has been adjusted to 7.0 with a 5% solution of sodium hydroxide.

Example 15

Liquid A15 - Mixed liquid formed from a 5% aqueous solution of disodium phosphate with a 1% aqueous solution of sodium phosphate, which has been adjusted to pH 7.0 with a 5% aqueous solution of sodium phosphate.

Liquid B15 - 10% aqueous solution of calcium chloride, which has been adjusted to pH 7.0 with a hydrochloric acid solution.

Example 16

Liquid A16 - 2.5% aqueous solution of disodium phosphate, which has been adjusted to pH 7.4 with a 2.5% aqueous solution of sodium phosphate.

Liquid B16 - 5% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 17

Liquid Al7 - 10% aqueous solution of disodium phosphate, which was adjusted to pH 7.4 with a 10% aqueous solution of sodium phosphate.

Liquid B17 - 15% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 18

Liquid A18 - 2.5% aqueous solution of disodium phosphate, which has been adjusted to pH 7.4 with a 5% aqueous solution of monopotassium phosphate.

Liquid B18 - 10% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 19

Liquid A19 - 2.5% aqueous solution of dipotassium phosphate, which has been adjusted to pH 7.4 with a 2.5% aqueous solution of sodium phosphate.

Liquid B19 - 5% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 20

Liquid A20 - 5% aqueous solution of dipotassium phosphate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B20 - 5% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 21

Liquid A21 - 10% aqueous solution of dipotassium phosphate, which has been adjusted to pH 7.4 with a 10% aqueous solution of sodium phosphate.

Liquid B21 - 5% solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 22

Liquid A22 - 20% aqueous solution of dipotassium phosphate, which has been adjusted to pH 7.4 with a 20% aqueous solution of sodium phosphate.

Liquid B22 - 10% aqueous solution of calcium chloride, which has been adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

Example 23

A 5% aqueous solution of disodium phosphate was prepared as liquid A23, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Next, a 10% aqueous solution of calcium chloride was prepared as liquid B23.

The affected area of a patient with hypersensitivity was cleaned and dried, and liquid A23 was applied to it using a sponge. Then, liquid B23 was applied to the layer of liquid A23 using a pad. The pain was immediately removed in the patient.

Example 2k

A 5% aqueous solution of disodium phosphate was prepared as liquid A24. A 10% aqueous solution of calcium chloride was then prepared as liquid B24 ·.

The affected area in a patient with hypersensitivity was cleaned and dried, and A24 liquid was applied to it with a tampon. Then, liquid B24 was applied to the layer of liquid A24 from another dental plaque using a tampon. The pain was immediately removed in the patient. Example 25

A 5% aqueous solution of disodium phosphate was prepared as liquid A25, which was then adjusted to pH 7, ^ with a 5% aqueous solution of monosodium phosphate.

5% calcium chloride was then dissolved in an aqueous solution containing 25% 2-hydroxyethyl methacrylate to form liquid B25, which was in turn adjusted to pH 7.2 with an aqueous solution. 5% hydrochloric acid.

For filling with dental resin, a Class I cavity was formed in the first lower molar of a patient. To remove the layers of dirt, a cavity cleaning device - marketed by G-C Dental Industrial Corp. under the name "Dentine Conditioner" - was applied to the cavity, followed by cleaning with water and drying. Liquid A25 was then applied to the cavity using a sponge, then liquid B25 was applied to the layer of liquid A25 using a pad. The resulting layers were left to stand for approximately 30 seconds. Air was then blown into the cavity using a dental syringe to dry the layers, followed by application of a light-curing composition comprising 30% 2-hydroxymethyl methacrylate, 68% methylene glycol dimethacryiate, 1% dimethylaminoethyl methacrylate and 1% camphor-quinone. The resulting layers were exposed to visible light using a dental visible light irradiator for one minute to induce setting. Then, a resin-hardening type - marketed by G-C Dental Industrial

Corp., under the name "Graft LC" - was introduced into the cavity and caused to set by 30 seconds of visible light irradiation using a dental visible light irradiation device. The patient was almost completely relieved of pain and a good condition was maintained even after a period of one month.

Examples 26 and 27

The procedures of Example 25 were followed except that liquids A26-27 and B26-27 were used below. The results are the same as those cited in Example 25.

Liquid A26 - 5% aqueous solution of disodium phosphate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Liquid B26 - 10% zinc oxide was dissolved in an aqueous solution containing 30% 2-hydroxyethyl methacrylate, which was adjusted to pH 7.4 with a 5% aqueous solution of hydroxide sodium.

Liquid A27 - Mixed liquid of a 5% aqueous solution of disodium phosphate with a 1% aqueous solution of sodium vinyl benzoate, which has been adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate. Liquid B27 - 10% calcium chloride was dissolved in an aqueous solution containing 20% 2-hydroxyethyl methacrylate, which was adjusted to pH 7.4 with a 5% aqueous hydrochloric acid solution.

Example 28

A 5% aqueous solution of disodium phosphate was prepared as liquid A28, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Next, a 10% aqueous solution of sodium chloride was prepared as liquid B28, which was in turn adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

For filling with dental resin, a Class I cavity was formed in the first upper molar of a patient. To remove the layers of dirt, a cavity cleaning agent - sold by G-C Dental Industrial Corp. under the name "Dentine Conditioner" - was applied to the cavity, followed by washing with water and drying. Then, liquid A28 was applied to the cavity using a pad, and then liquid B28 was applied to the layer of liquid A28 using a pad. The resulting layers were left to stand for about one minute. Air was then blown onto the cavity using a dental syringe to dry the layers, followed by application of a light-curing composition - marketed by Kuraray Co., Ltd., under the name " Photobond ". The resulting layers were exposed to visible light using a dental visible light irradiator for one minute to induce setting. Then, a light-curing type resin - marketed by Kuraray Co., Ltd., under the name "PhotoClearfil" - was introduced into the cavity and caused to set by 60 seconds irradiation of visible light using a dental device with visible light irradiation. The patient was almost completely free of pain and a good condition was maintained even after a period of two months had elapsed.

Example 29

A 5% aqueous solution of disodium phosphate was mixed with 1% sodium vinyl benzoate to prepare an A29 liquid, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Next, a 10% aqueous solution of calcium chloride was prepared as liquid B29, which was in turn adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

For filling with dental resin, a Class I cavity was formed in the first upper molar of a patient. To remove the layers of dirt, a cavity cleaning agent - sold by G-C Dental Industrial Corp., under the name "Dentine Conditioner" - was applied to the cavity, followed by cleaning with water and drying. Then, liquid A29 was applied to the cavity using a pad, and liquid B29 was then applied to the layer of liquid A29 using a pad. The resulting layers were left to stand for about 30 seconds. Air was then blown onto the cavity using a dental syringe to dry the layers, followed by application of a light-curing composition - marketed by Kuraray Co., Ltd., under the name " Photobond ". The resulting layers were exposed to visible light using a visible light irradiator for 30 seconds to ensure setting. Then, a light hardening type resin - marketed by Kuraray Co., Ltd., under the name "Photo-Clearfil" - was introduced into the cavity and caused to set by 60 second irradiation. visible light using a dental visible light irradiation device. The patient was practically completely relieved of the pain, such a condition being maintained even after a period of three months had elapsed. Example 30

The procedures of Example 29 were followed except that a 5% aqueous solution of disodium phosphate adjusted to pH 7.4 was used as liquid A30 with a 5% aqueous solution of sodium phosphate; a 30% aqueous solution of 2-hydroxyethyl metacrylate in which 5% sodium chloride was dissolved and which was adjusted to pH 7.4 with a 5% aqueous solution was used as liquid B30 hydrochloric acid; the layers were exposed to visible light for one minute. The results are identical to those mentioned in Example 29.

Example 31

A 5% aqueous solution of disodium phosphate was prepared as liquid A31, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Then, as liquid B31, a 10% aqueous solution of calcium chloride was prepared, which was in turn adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

For filling with dental resin, a Class I cavity was formed in the lower second premolar of a patient. To remove the layers of dirt, a cavity cleaning agent - sold by G-C Dental Industrial Corp., under the name "Dentine Conditioner" - was applied to the cavity, followed by cleaning with water and drying. Then, liquid A31 was applied to the cavity using a pad and then liquid B31 was applied to the layer of liquid A31 using a pad. The resulting layers were left to stand for approximately 30 seconds.

Air was then blown onto the cavity with a dental syringe to dry the layers, followed by sealing and setting using a light-curing type resin - available from ICI Co., Ltd., under the name "Occlusin". The patient was almost completely free of pain and a good condition was maintained even after one month had passed.

Example 32

The procedures of Example 31 were followed except that a mixture of a 3% aqueous solution of disodium phosphate with a 6% aqueous solution of sodium vinyl benzoate, which was adjusted to pH 7, 4 with a 5% aqueous solution of monosodium phosphate, was used as liquid A32; and was used, as liquid B32, a 10% aqueous solution of calcium chloride adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid. The results, even after two months had passed, were the same as those mentioned in Example 31.

EXAMPLE 33 A 5% aqueous solution of disodium phosphate was prepared as liquid A33, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate. Next, a 10% aqueous solution of zinc chloride was prepared as liquid B33, which was in turn adjusted to pH 7.4 with a 5% aqueous solution of sodium hydroxide.

For filling with dental resin, a Class I cavity was formed in the lower second premolar of a patient. To remove the layers of dirt, a cavity cleaning agent - sold by G-C. Dental Industrial Corp., under the name "GC Dentine Conditioner" - was applied to the cavity, followed by cleaning with water and drying. Then, liquid A33 was applied to the cavity using a pad, and then liquid B33 was applied to the layer of liquid A33 using a pad. The resulting layers were left to stand for about 30 seconds.

Air was then blown over the cavity using a dental syringe to dry the layers, followed by application of a light-curing composition comprising 30% 2-hydroxyethyl metacrylate, 68% triethylene glycol dimethacrylate , 1% dimethylaminoethyl methacrylate and 1% camphor-quinone.

The resulting layers were exposed to visible light using a visible light irradiator for one minute to ensure setting. Then, a light-curing type resin - marketed by GC Dental Industrial Corp., under the name "GC Graft LC" - was introduced into the cavity and caused to set by 30 second irradiation of visible light using a dental visible light irradiation device. The patient was almost completely free of pain and a good condition was maintained even after a period of three months had elapsed.

Example 34

A 5% aqueous solution of disodium phosphate was prepared as liquid A34, which was then adjusted to pH 7.4 · with a 5% aqueous solution of sodium phosphate.

Next, a 10% aqueous solution of calcium chloride was prepared as liquid B34, which in turn was adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

After preparing a tooth for a fixed prosthesis with a diamond tip, the affected area of a patient was cleaned and dried. Liquid A34 was applied to the affected area using a pad, and then liquid B34 was applied to layer A34 using a pad. The patient was immediately released from pain.

Example 35

A 5% aqueous solution of disodium phosphate was mixed with a 2% aqueous solution of sodium fluoride to prepare the liquid A35, which was adjusted to pH 7.2 with a 5% aqueous solution of sodium phosphate. Next, a 10% aqueous solution of calcium chloride was prepared as liquid B35 which was in turn adjusted to pH 7.2 with a 5% aqueous solution of hydrochloric acid.

When the affected area of a patient suffering from a "forked" complication was subjected to grinding, the patient complained of pain. After cleaning and drying the infected region, the liquid A35 was applied to this region using a tampon and the liquid B35 was applied to the layer of liquid A35 with a tampon. The patient was immediately relieved of his pain.

Example 36

A 10% aqueous solution of disodium phosphate was prepared as liquid A36, which was then adjusted to pH 7.4 with a 5% aqueous solution of sodium phosphate.

Next, a 15% aqueous solution of calcium chloride was prepared as liquid B36, which in turn was adjusted to pH 7.4 with a 5% aqueous solution of hydrochloric acid.

After the molar to receive root canal treatment has been milled and filed to enlarge the root canal and this root canal has been cleaned internally, it has been cleaned internally again using liquid A36, using a dental syringe. Then the B36 fluid was expelled into the root canal near the apical foramen, again using a dental syringe. Paper tips were then used to remove excess liquid, which was followed by an X-ray inspection. After confirmation that the apical foramen had been closed, spikes of gutta-percha were inserted into the root canal. After six months, an x-ray confirmed that the periradicular and periodontal tissues had remained in good condition.

Comparative Example 1

A silver diamine-fluoride preparation containing a silver diamine-fluoride solution - marketed by Bibrand Medico Dental Co., Ltd. under the name "Saforide" - was applied to a patient complaining of hypersensitivity, but the patient was not relieved of pain. This patient's teeth turned black.

Comparative Example 2

The patient was exposed to a laser beam for 30 seconds using the "Stmalaser" device manufactured by Sedatelec Co., Ltd. The pain was removed from the upper jaw, but the lower jaw was still painful.

Comparative Example 3

For filling with dental resin, a Class II cavity was formed in the first upper molar of a patient. A light-curing composition - marketed by Kuraray Co., Ltd., under the name "PhotoBond" - was applied to the cavity and was caused to cure by exposure of one minute to visible light using a dental device for irradiating visible light. Then, a light-curing type resin - marketed by Kuraray Co., Ltd., under the name "" PhotoClearfiil "- was introduced into the cavity, followed by exposure for 30 seconds to visible light using a visible light irradiation appliance. Immediately after the obturation, the patient complained of pain. This pain continued for a week. On the tenth day, as the pain became more serious, a pulpectomy was performed.

Comparative Example 4 ·

A molar to receive root canal treatment was reamed and filed to enlarge the root canal and it was thoroughly cleaned inside. Then, paper points were used to remove excess water and then gutta-percha points were introduced into the root canal. After filling, an X-ray showed that the point crossed about 1 mm through the apex of the root. The next day, the inflammation increased and the pain increased. Then the root canal treatment had to be done again.

According to the present invention, the liquids A and B containing substances capable of forming precipitates which are difficult to dissolve, and this quickly by mixing, are applied in succession to the affected zone on which these liquids can react with each other to form the difficult-to-dissolve substance, thereby sealing an elongated dentinal tubule.

Liquid A is mainly an aqueous solution containing 1 to 70% of one or more sodium, potassium and lithium salts of inorganic or organic acids, while liquid B is mainly an aqueous solution containing 1 to 70% of one or more chlorides, nitrates, sulfates and acetates of calcium, zinc, strontium, magnesium, aluminum, barium, iron, copper, silver, lead or tin.

When the odontotherapeutic material according to the invention is used as a lenitive agent for hypersensitivity, the liquid A is applied to the affected area, already cleaned and dried, using a pad, and the liquid B is then applied to the layer of the liquid A thanks to a tampon. The order of application of liquids A and B can be reversed.

When the odontotherapeutic material according to the present invention is used as a lenitive agent for a pulpalgia (or as a preparative coating agent), a cavity cleaning agent marketed by G-C. Dental Industrial Corp., under the name "GC Dentine Condition" is applied to the dentin part of the affected area to remove layers of dirt, followed by cleaning and drying of the affected area. Liquid A is applied to this affected area with a pad * and liquid B is applied over the layer of liquid A with a pad as well. Then, a dental bonding material is applied to the resulting layers to ensure setting. The order of application of liquids A and B can be reversed.

When the odontotherapeutic material according to the invention is used to seal the apex of the root in the root canal, this root canal is enlarged by a wick, a file, etc., and it is then thoroughly cleaned inside. The root canal is then cleaned again inside using liquid A, using a dental syringe. Then, liquid B is forcibly removed through the apex of the root into the root canal, again using a syringe. The order of application of liquids A and B can be reversed.

As detailed above, when the odontotherapeutic material according to the present invention is used as a lenitive agent for hypersensitivity, liquids A and B, with or without pH adjustment, are applied in succession to the affected area in order of a reaction between them, forming a substance difficult to dissolve, capable of sealing elongated dentinal tubules. This makes it possible to control a movement of fluid in the dentinal tubules, to which the hydrodynamic theory of Brännström refers, by interrupting the stimuli towards the dental pulp.

The odontotherapeutic material according to the present invention can also satisfy the eight requirements listed below, which the traditional lenitive agent for hypersensitivity is supposed to present: (1) it should not be stimulating for dental pulp and gums, and reduce to minimizing or eliminating the pain caused; (2) it should not cause damage to the teeth; (3) it should not cause discoloration of the teeth; (4) it should produce its effect through simple work; (5) it should take effect immediately; (6) it should maintain its effect; (7) it should not cause pain to the patient during or after treatment; and (8) it should dispense with a special installation or apparatus.

When the odontotherapeutic material according to the present invention is used as a lenitive agent for pulpalgia (preparatory coating agent), the liquids A and B, with or without adjustment of the pH, are applied in succession to the affected region, on which they are brought to react with each other to form a substance which is difficult to dissolve in the dentinal tubules and on the dental surface, this substance then being able to set with or without a light-curing composition. This makes it possible to control a movement of fluid in the tubules, as envisaged in the hydrodynamic theory of Brännström, by interrupting the stimuli at the dental pulp.

The odontotherapeutic material according to the present invention also allows the use of coatings or dental cements available on the market as bases to be placed, and the use of dental resins to be placed on top, with great safety. On the whole, the odontotherapeutic material according to the present invention can satisfy the nine requirements listed below, which a traditional agent for pulpalgia is supposed to present: (1) it should not be stimulating for dental pulp and gums, and minimize or eliminate the pain caused; (2) it should not cause damage to the dentin (3) it should not cause discoloration of the dentin; (ii) it should produce its effect through simple work; (5) it should take effect immediately; (6) it should maintain its effect; (7) it should not cause pain to the patient during or after treatment; (8) it should not involve special equipment or apparatus; and (9) it should not participate in the polymerization of the resin.

In addition, the odontotherapeutic material according to the invention can be used after scaling or grinding of the roots.

Odontotherapeutic material can also be used to find out if the pain is caused by hypersensitivity or pulpitis.

In addition, when the odontotherapeutic material according to the present invention is used to seal the apex of the root canal, the liquids A and B, with or without adjustment of the pH, are successively introduced by force into the root canal, into which they are brought to react with each other to form a substance that is difficult to dissolve and thereby seal the apex of the root. In this way, one can avoid the push of a point of gutta-percha through the apex of the root, which is one of the problems encountered with traditional materials.

Claims (9)

1. Odontotherapeutic material, based on two liquids A and B, containing materials capable of forming precipitates that are difficult to dissolve, and this immediately upon mixing, these liquids A and B being applied in succession to the affected area. 2. The odontotherapeutic material of claim 1, which is adapted to be brought to set with a light-curing composition. 3. odontotherapeutic material according to claim 1 or 2, wherein A is an aqueous solution containing 1 to 70% of one or more sodium, potassium and lithium salts of inorganic acids or organic acids. k. Odontotherapeutic material according to claim 1 or 2, wherein the liquid B is an aqueous solution containing 1 to 70% of one or more calcium, zinc, strontium, magnesium, aluminum chlorides, nitrates, sulfates and acetates , barium, iron, copper, silver, lead and tin, or calcium chloride, zinc chloride or strontium chloride. 5. odontotherapeutic material according to claim 3, in which the inorganic acids are chosen from the group comprising phosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, methaphosphoric acid, polyphosphoric acid, phosphonic acid, phosphinic acid, sulfuric acid, sulfurous acid, carbonic acid, hydrogen fluoride, hydrogen sulfide and silicic acid, or sodium phosphate, potassium phosphate, sodium fluoride or sodium pyrophosphate. 6. odontotherapeutic material according to claim 3, in which the organic acids are chosen from the group comprising acids containing, as acid groups, the carboxyl, phosphoric, thiophosphoric, pyrophosphoric, phosphonic, phosphinic and sulfone groups. 7. The odontotherapeutic material according to claim 3, wherein the organic acid is a polymer. 8. The odontotherapeutic material according to claim 3 or claim 6, wherein the organic acid has a polymerizable double bond. 9. odontotherapeutic material according to any one of claims 1, 2, 3 or 8, in which the liquids A and / or B contain, in addition to water and essential components, a monomeric material containing one or more hydrophilic groups , such as hydroxyl, carboxyl and sulfone groups and, at the same time, a polymerizable double bond. 10. odontotherapeutic material according to any one of claims 1, 2, 3 or 8, in which the liquids A and / or B contain, in addition to water and essential components, 1 to 70% of 2- methacrylate hydroxyethyl.