JPH0753323A - Photosetting packing material for tooth - Google Patents

Abstract

PURPOSE:To provide a photosetting packing material for tooth containing a filler capable of exhibiting dental pulp-protecting effect equivalent to calcium hydroxide preparation and not exerting a bad influence upon stability of a photopolymerizable resin. CONSTITUTION:In the photosetting packing material for tooth containing a component A consisting of a radical polymerizable unsaturated monomer, a component B consisting of a photosensitizer and a component C consisting of a filler, at least magnesium oxide powder is included as the component C and the weight ratio of magnesium oxide is 2-60wt.% based on total amount of photosetting packing material. Since magnesium oxide powder contained as the filler exhibits excellent dental pulp-protecting effect and the packing material is free from lowering of photosetting properties of the resin with the passage of time and free from deterioration of compression strength of the resultant cured product with the passage with time, the packing material is especially suitable in use as a lining agent or a capping agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocurable filling material for teeth which is suitable for use as a backing agent or a covering agent.

[0002]

2. Description of the Related Art In the field of dental preservation, in order to protect the pulp and maintain its function, the direct pulp capping method in which the exposed pulp is directly coated with a drug (covering agent), or a single-layer tooth is used. An indirect pulp capping method has been performed in which the pulp is indirectly coated with a drug (lining agent) across the quality. In these pulp pulping methods, water is used as a drug (capsule covering agent) for coating the pulp. Calcium oxide formulations have been widely used. Examples of such calcium hydroxide preparations include calcium hydroxide alone and calcium hydroxide cement, and the calcium hydroxide (Ca) contained in these calcium hydroxide preparations.
(OH) ₂ ) not only has a sedative effect, but also has the advantage of promoting the formation of eaves hard tissue.

However, since this calcium hydroxide is a substance exhibiting a strong alkalinity, a filler obtained by mixing calcium hydroxide with a radically polymerizable resin for teeth is used as a backing agent or a covering agent. When it is used, there are problems that the stability of the resin is impaired, a decrease in photocurability with time is observed, and the compression strength of the obtained cured product deteriorates with time.

To date, photocurable filling materials for teeth have been proposed which have a pulp protection effect equivalent to that of calcium hydroxide preparations and which do not affect the temporal stability of the radical-polymerizable resin. Not not.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems, to show a pulp protecting effect equivalent to that of a calcium hydroxide preparation, and to prevent the stability of the photopolymerizable resin from being adversely affected. Another object of the present invention is to provide a photocurable filling material for teeth containing a different filler.

[0006]

The photo-curable filling material for teeth of the present invention is a tooth containing component A: radically polymerizable unsaturated monomer, component B: photosensitizer, and component C: filler. In the photocurable filling material for dental use, at least magnesium oxide powder is contained as the component C, and the weight ratio of the magnesium oxide powder in the whole photocurable filling material for teeth is 2 to 60% by weight. Characterize.

That is, the photocurable filling material for teeth of the present invention includes all the constituents of the conventionally known filling material (radical-polymerizable unsaturated monomer, photosensitizer, and filler). Of these, the essential component of the filler is magnesium oxide powder, and the weight ratio of the magnesium oxide powder to the entire photocurable filling material for teeth is within a certain range. And In the present invention, the content of the magnesium oxide powder contained as the component C is 2% of the whole photocurable filling material for teeth.
-60% by weight, with a range of 10-40% by weight being particularly preferred. If the content of magnesium oxide powder is 2% by weight
In the following cases, the effects such as sedation, promotion of eaves lid hard tissue formation, and stimulation block are reduced. Conversely, when the content of magnesium oxide powder is 60% by weight or more, the resin component in the entire filling material is reduced. The ratio of (Component A) becomes small and the curing performance of the filling material decreases. In the present invention, as such a magnesium oxide powder, a commercially available product, for example, magnesium oxide of the Japanese Pharmacopoeia can be used as it is without treatment, but it may be surface-treated by titanate treatment, silane coupling treatment, or the like.

Since the magnesium oxide powder contained in the photocurable filling material for teeth of the present invention exhibits an excellent eaves lid hard tissue forming ability, by using the filling material of the present invention,
The condition of the dental pulp can be maintained and preserved. Moreover, since this magnesium oxide powder is not a strongly alkaline substance such as conventional calcium hydroxide, the temporal stability of the radically polymerizable unsaturated monomer is not adversely affected.

On the other hand, as the radically polymerizable monomer contained as the component A, various commercially available dental polymerizable resins can be used, but methacrylic acid ester vinyl monomers and acrylic acid ester vinyl monomers are preferable.
Further, urethane dimethacrylate, triethylene glycol dimethacrylate and the like are also preferable. The content ratio of the component A in the filling material of the present invention is appropriately selected according to the content ratio of the filler of the component C, but it is generally preferably 20 to 70% by weight based on the whole filling material.

Further, the component B in the present invention is a photosensitizer (photopolymerization catalyst) for accelerating the polymerization of the above-mentioned radical-polymerizable monomer, and commercially available products known so far are widely used. However, camphor quinone and the like are preferable. The content ratio of this component B in the whole filling material is
Generally, it is 1% by weight or less. In addition, the photo-curable filling material for teeth of the present invention may contain a reducing agent and a stabilizer known so far in dental applications.

The filling material of the present invention generally contains barium sulfate as a filler in addition to the essential compound magnesium oxide. In this case,
The X-ray contrast property is imparted. In the present invention, fluoroaluminosilicate glass or the like may be contained in place of the barium sulfate, and silica or barium glass or the like may be contained in addition thereto.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

EXAMPLE A photocurable filling material for teeth of the present invention having the composition described in Examples 1 to 5 and a comparative example were prepared by mixing the components in the ratios shown in Table 1 below. The described conventional product (containing calcium hydroxide) was produced. At this time, as the magnesium oxide powder, a commercially available product of the Japanese Pharmacopoeia (Toda Pharmaceutical Co., Ltd., light quality) was used without treatment.

[0013]

[Table 1]

Then, each of the filling materials is stored at room temperature while shielding the light, and after 1 day, 3 days after production (formulation),
After 1 week and 3 months, the mold (diameter 3m
m, cylinder with a depth of 12 mm), the upper part is covered with a cover glass, and visible light (wavelength 35
0 to 700 nm) for 30 seconds to cure. For each cured sample, the product was removed from the mold, the uncured portion was removed, and the cure depth for each fill material was measured. The results of this experiment are shown in Table 2. The curing depth is a value indicating how deep the polymerization reaches by constant light irradiation (unit: mm). The larger this value is, the more curable the inside of the filling material is. Indicates that the filling property is good, and that this value is small indicates that only the surface layer portion of the filling material is cured and the polymerizability is poor.

[0015]

[Table 2]

As shown in Table 2, in the case where the photocurable filling material for teeth of the present invention is used (Examples 1 to 5), even after 3 months have passed since the production (after compounding). It was confirmed that no decrease in the curing depth was observed. On the contrary,
In the case of conventional fillers containing calcium hydroxide,
It was confirmed that the curing depth was remarkably lowered after 3 months from the production, and it was found that the inside of the filling material was hard to be cured.

Similarly, with respect to the filling materials described in Examples 1 to 5 and Comparative Example, changes in compressive strength with time were measured. The results are shown in Table 3 below.

[0018]

[Table 3]

As shown in Table 3, when the photocurable filling material for teeth of the present invention is used (Examples 1 to 5), compression of the cured product is obtained even after 3 months from the production. It was confirmed that no decrease in strength was observed. On the other hand, in the case of a cured product obtained by using a conventional filler containing calcium hydroxide, it was confirmed that a significant decrease in compressive strength occurs after 1 to 3 months of production. .

[0020]

INDUSTRIAL APPLICABILITY The photocurable filling material for teeth of the present invention does not contain calcium hydroxide which is strongly alkaline, but contains magnesium oxide having an excellent pulp-protecting effect equivalent to that of calcium hydroxide. It is particularly suitable for use as an agent or a covering agent. Further, in the case of the filling material of the present invention, an excellent advantage that the photocurability of the resin does not decrease with time and the compression strength of the obtained cured product does not deteriorate with time is obtained.

Claims (1)

[Claims] 1. A photocurable filling material for teeth comprising a component A: a radically polymerizable unsaturated monomer, a component B: a photosensitizer, and a component C: a filler, wherein the component C is at least magnesium oxide. A photocurable filling material for teeth, comprising a powder, and the weight ratio of the magnesium oxide powder in the entire photocurable filling material for teeth is 2 to 60% by weight.