JPS6332049B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a cement material for dental treatment, and more particularly to a cement material for dental treatment containing alumina cement as a main component and suitable for use as a pulp capping agent, root canal filling agent, sealing agent, bone defect repair agent, etc. . In the field of dental treatment, it is used as a root canal filling agent to cure infected root canals by occluding the pulp cavity after the pulp tissue has been removed, or as a pulp covering agent to protect the pulp during cavity formation. Various materials are used. However, the reality is that so far nothing has been found that is fully satisfactory. Now, using root canal filling materials as an example, materials suitable for this are generally non-irritating, non-toxic, have affinity with tissues and compatibility with the root canal wall, It has antibacterial or healing effects, is strong, does not cause volume changes, is insoluble in tissue fluids, is flexible and can be retreated, has contrast properties, and is easy to handle. The ideal is to satisfy certain conditions such as: Among these, the contrast property can be solved by mixing an appropriate contrast medium, but other conditions largely depend on the characteristics of the root canal filling material itself. For example, one of the typical root canal filling materials that has been widely used in the past is one that uses zinc oxide/eugenol-based materials, but since these are acidic materials, they are irritating and It has no healing properties. Another representative thing is
Some materials use calcium hydroxide materials, but these have low strength and are strongly alkaline, so they may damage tissues and deteriorate into calcium carbonate over time. In addition, root canal filling agents using formaldehyde-based materials or iodoform-based materials are also used, but each has advantages and disadvantages, and nothing that fully satisfies the above conditions has yet been developed. There isn't. The present invention was made in view of the above circumstances, and focused on the possibility of using industrial alumina cement, which was not anticipated by anyone involved in the dental field. This was a successful improvement of cement to make it suitable as a material for dental treatment. That is, the present invention comprises alumina cement powder, a calcium-based powder hardening agent in a proportion of 1 to 50 parts by weight per 100 parts by weight of this cement powder, and a hardening retarder capable of suppressing the diffusion of calcium ions as essential components. This is a cement material for dental treatment. The main component, alumina cement powder, is composed of calcium aluminate (CaO・Al ₂ O ₃ ) with a ratio of approximately 80% by weight of aluminum oxide and approximately 20% by weight of calcium oxide, and is similar to commercially available industrial cement. It is easily and inexpensively available. Further, the calcium-based powder hardening agent used in the present invention is, for example, a powder of calcium hydroxide, calcium chloride, or calcium oxide, and calcium hydroxide powder is particularly preferably used. As mentioned above, the amount of the calcium-based powder hardening agent needs to be 1 to 50 parts by weight per 100 parts by weight of the alumina cement powder. This is less than 1 part by weight,
It takes a long time for the cement material to harden and the strength of the hardened product decreases, making it unsuitable as a therapeutic material such as pulp capping agent or root canal filling agent. For example, the curing speed and alkalinity become too high, which has a negative effect on handling and healing effects. For this reason, when comparing and weighing curing time, strength, healing effect, etc., the proportion of calcium-based powder hardening agent should be
The optimal amount is about 20 parts by weight, and when this proportion is used, a cement material with great strength and healing effects and good handling properties can be obtained. On the other hand, the curing retarder used in the present invention is a low molecular weight compound such as polyvinyl alcohol, polyvinylpyrrolidone, gum arabic, sodium polyacrylate, sodium silicate, glycerin, etc. that can suppress the diffusion of calcium ions involved in the curing of alumina cement. A fatty acid or a hydrophilic natural resin,
These may be used alone or in combination of two or more. Such a hardening retarder is alumina cement powder 100
The ratio is preferably 1 to 20 parts by weight. If it is less than 1 part by weight, the curing retardation effect is insufficient and the cement material will harden in a very short period of time, whereas if it exceeds 20 parts by weight, the curing retardation effect will be excessive and it will not harden. This is because a long time is required, resulting in a composition that is unsuitable for dental treatment cement materials. The cement material of the present invention contains the above-mentioned alumina cement powder, calcium-based powder hardening agent, and hardening retardant as essential components, but if necessary,
For example, fillers such as titanium oxide powder and aluminum oxide powder are added to increase strength, and preservatives such as iodoform and polaform are added.
Of course, it is also possible to add various known contrast agents and antiinflammatory agents. There is no particular restriction on the ratio of such secondary components, and it may be determined as appropriate. The cement materials for dental treatment of the present invention as described above can be divided into the following four types depending on the storage form before use. The first type is a powder/liquid type that is stored separately into a mixed powder containing at least alumina cement powder and a calcium-based hardening agent, and a liquid in which at least a hardening retarder is dissolved or dispersed in water, etc. The second type of composition is stored separately into a powder containing at least alumina cement powder and a paste obtained by adding and kneading a calcium-based powder hardening agent to at least a solution or dispersion of a hardening retarder. The third type is a powder/paste type composition, and the third type is a paste made by adding and kneading at least alumina cement powder and a calcium-based powder hardening agent to glycerin or the like;
It is a paste/liquid type composition that is stored separately from a liquid in which at least a hardening retardant is dissolved or dispersed, and the fourth type is a paste made by adding and kneading at least alumina cement powder to glycerin or the like. It is a paste/paste type cement material that is stored separately from a paste made by adding and kneading a calcium-based powder hardening agent to at least a solution or dispersion of a hardening retarder. Therefore, when adding the above-mentioned subsidiary ingredients, for example, if it is a powder/liquid type cement material, fillers etc. should be added to the powder side and preservatives and anti-inflammatory agents etc. to the liquid side. As usual, it is best to add the secondary ingredients to one or both of the preservative systems of the cement material in advance, or to mix the secondary ingredients when mixing and using both preservative systems. Just do it. As described above, the cement material for dental treatment of the present invention has alumina cement powder as its main component, and the calcium-based powder hardening agent is contained in a proportion of 1 to 50 parts by weight based on 100 parts by weight of the cement powder. Then,
Since this cement material is designed to exhibit appropriate alkalinity when used as a mixture, when used as a root canal filling agent or pulp covering agent, this cement material exhibits antibacterial and healing effects due to its moderate alkalinity. Because it produces a hydrated gel composition on the surface, it exhibits good compatibility with root canal walls and cavity walls, and good affinity with tissues. Then, add a hardening retarder to the alumina cement powder as described above.
In case of 1 to 20 parts by weight per 100 parts by weight,
This makes it an easy-to-handle cement material that takes a few minutes to several tens of minutes to harden. Furthermore, the composition of the present invention has almost no toxicity or irritation, and its cured product has high strength, does not cause volume change, is insoluble in interstitial fluid, and is extremely durable. It has the advantages of not inhibiting the polymerization of room-temperature polymerized resins, and has good flexibility, making retreatment easy, and is therefore fully satisfactory as a cement material for dental treatment. It is. Next, the present invention will be described in more detail with reference to Examples. Example 1 20% by weight of calcium hydroxide was added to commercially available alumina cement powder ( _Al2O3 : 80% by weight, CaO: 20% _by weight) and mixed in a porcelain crucible for 2 hours to prepare a mixed powder. . Next, polyvinyl alcohol 4
Aqueous solutions having four different concentrations of 4% by weight, 6% by weight, 8% by weight and 10% by weight were prepared to obtain powder/liquid cement materials. Next, each aqueous solution was added and kneaded to the mixed powder in the proportions shown in Table 1 below, and the curing time, consistency, solubility, PH change, compressive strength, and cytotoxicity were measured for each kneaded composition. did. The results are also listed in Table 1. Incidentally, the measurement was carried out by the following method. Curing time: ADA-No.16 Consistency: ADA-No.16 Solubility: ADA-No.8 PH change: Same method as solubility measurement Compressive strength: ADA-No.8 Cytotoxicity: Tissue culture method

【table】

[Table] Example 2 For the mixed powder prepared in Example 1, Example 1
50% by weight in each of 6% by weight, 8% by weight and 10% by weight polyvinyl alcohol aqueous solutions prepared in
of titanium oxide was added and kneaded according to the formulation shown in Table 2, and the same measurements as in Example 1 were performed on each kneaded product. The results are also listed in Table 2.

【table】

[Table] Example 3 Powder was prepared in the same manner as in Example 1, except that polyvinylpyrrolidone and gum arabic were used instead of polyvinyl alcohol as the curing retarder.
A liquid composition was obtained and various measurements were performed.
The results are shown in Table 3. However, all of the measured values in Table 3 do not display the obtained measured values individually, but instead show the minimum and maximum values.

【table】

[Table] From the measurement results of the above examples, the cement material for dental treatment of the present invention has an appropriate hardening time and consistency, high strength, low solubility, and has an appropriate pH.
It can be seen that it is a useful product with extremely low toxicity.

Claims (1)

[Claims] 1 Alumina cement powder, a calcium-based powder hardening agent in a proportion of 1 to 50 parts by weight per 100 parts by weight of the cement powder, and a hardening retardant capable of controlling the diffusion of calcium ions as essential components. Cement material for dental treatment. 2. The cement material according to claim 1, wherein the curing retarder is contained in a proportion of 1 to 20 parts by weight per 100 parts by weight of alumina cement powder. 3. Claim 1 of a powder/liquid system consisting of a mixed powder containing at least an alumina cement powder and a calcium-based powder hardening agent, and a liquid in which at least a hardening retarder is dissolved or dispersed.
Cement material according to paragraph 2 or paragraph 2. 4. The cement material according to claim 1 or 2, which is a powder/paste type, comprising a powder containing at least alumina cement powder, and a paste containing at least a calcium-based powder hardening agent and a hardening retardant. 5. Claim 1 of a paste/liquid system consisting of a paste containing at least alumina cement powder and a calcium-based powder hardening agent, and a liquid in which at least a hardening retardant is dissolved or dispersed.
Cement material according to paragraph 2 or paragraph 2. 6. The paste-paste cement material according to claim 1 or 2, which is a paste-based cement material comprising a paste containing at least alumina cement powder and a paste containing at least a calcium-based powder hardening agent and a hardening retardant. 7 As a curing retarder, polyvinyl alcohol,
Claims 1 to 1 which use one or more selected from the group consisting of polyvinylpyrrolidone, gum arabic, sodium polyacrylate, sodium silicate, glycerin and other low molecular fatty acids, and hydrophilic natural resins. The cement material according to any of Item 6.