Block-like composite material for dental cutting and processing having multilayered structure including layers with different transparencies and containing fiber material

Abstract

The present invention relates to a composite material which can be used as a dental prosthesis device (crown, bridge), and specifically, relates to a composite material including a curable resin and a fiber material, and more specifically relates to a block-like composite material for dental cutting and processing characterized by having a multilayered structure including at least two layers having different transparencies. There are no technical information relating to a color tone and a transparency of the fiber material. To provide a block-like composite material for dental cutting and processing, wherein the block-like composite material has a multilayered structure including at least two layers having different transparencies, and the each layer includes a curable resin and a fiber material.

Claims

1. A block-like composite material for dental cutting and processing, wherein the block-like composite material has a multilayered structure comprising at least two layers having different transparencies including a highly transparent layer and a low transparent layer, wherein: the each layer includes a curable resin and a fiber material, the different transparencies are obtained by adjusting a difference in refractive indexes between the curable resin and the fiber material in each of the at least two layers, the highly transparent layer has a higher transparency than the low transparent layer, and a boundary between the layers consists of a flat plane.

2. The block-like composite material for dental cutting and processing according to claim 1, wherein, the block-like composite material includes three layers consisting of the highly transparent layer, a middle transparency layer and the low transparent layer, a contrast ratio of the highly transparent layer is less than 0.50, a contrast ratio of the middle transparency layer is 0.50 or more and less than 0.60, and a contrast ratio of the low transparent layer is 0.60 or more.

3. The block-like composite material for dental cutting and processing according to claim 1, wherein, the block-like composite material includes four or more layers comprising the highly transparent layer, a middle transparency layer and the low transparent layer, a contrast ratio of the highly transparent layer is less than 0.50, a contrast ratio of the middle transparency layer is 0.50 or more and less than 0.60, a contrast ratio of the low transparent layer is 0.60 or more, each of the highly transparent layer, the middle transparency layer and the low transparent layer consists of a single layer or a plurality of layers having different transparencies, and a difference of contrast ratio between each layer is 0.02 or more.

4. The block-like composite material for dental cutting and processing according to claim 1, wherein, a shape of the fiber material is at least one selected from the group consisting of roving, strand, yarn, sheet, ribbon, and tape.

5. The block-like composite material for dental cutting and processing according to claim 4, wherein, the fiber material is formed from a long-fiber material.

6. The block-like composite material for dental cutting and processing according to claim 4, wherein, the fiber material is formed from at least one selected from the group consisting of A-glass, C-glass, D-glass, E-glass, ECR-glass, AR-glass, R-glass, S-glass, alumina, zirconia, polyethylene, polyester, polyamide, and collagen.

7. The block-like composite material for dental cutting and processing according to claim 1, wherein, refractive indexes of the curable resins in the respective layers are the same as each other.

8. The block-like composite material for dental cutting and processing according to claim 1, wherein, a contrast ratio of the highly transparent layer is less than 0.50, and a contrast ratio of the low transparent layer is 0.50 or more.

9. The block-like composite material for dental cutting and processing according to claim 1, wherein, a content of the fiber material is from 30 to 70 wt % of the block-like composite material, and a content of a filler other than the fiber material is 50 wt % or less of the block-like composite material.

Description

EXAMPLES

(1) Hereinafter, Examples of the present invention are specifically described. However, the present invention is not intended to be limited to these Examples.

(2) Mixed liquid A of radical polymerizable monomer compounds was prepared by compounding 50 parts by weight of 2,2-bis[4-(3-methacryloxy)-2-hydroxypropoxyphenyl]propane (Bis-GMA), 50 parts by weight of triethylene glycol dimethacrylate (3G), and 0.3 parts by weight of benzoyl peroxide (BPO). The refractive index of a curable resin obtained by polymerizing and curing mixed liquid A of radical polymerizable monomer compounds was 1.535.

(3) Mixed liquid B of radical polymerizable monomer compounds was prepared by compounding 70 parts by weight of 1,6-bismethacrylethylcarbonylamino(2,2,4-)trimethylhexane (UDMA), 30 parts by weight of triethylene glycol dimethacrylate (3G), and 0.3 parts by weight of benzoyl peroxide (BPO). The refractive index of a curable resin obtained by polymerizing and curing mixed liquid B of radical polymerizable monomer compounds was 1.505.

(4) Mixed liquid C of radical polymerizable monomer compounds was prepared by compounding 70 parts by weight of 2,2-bis[4-(3-methacryloxy)-2-hydroxypropoxyphenyl]propane (Bis-GMA), 30 parts by weight of triethylene glycol dimethacrylate (3G), and 0.3 parts by weight of benzoyl peroxide (BPO). The refractive index of a curable resin obtained by polymerizing and curing mixed liquid C of radical polymerizable monomer compounds was 1.553.

(5) [Preliminary Test]

(6) E-glass fibers (refractive index: 1.558) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 1 mm. Mixed liquid A of radical polymerizable monomer compounds was poured in gaps between the E-glass fibers. Then, the content of the mixed liquid A of radical polymerizable monomer compounds was adjusted so that the content of the fiber material was 55 wt % and the content of mixed liquid A of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a plate-like composite material. The colorimetric value was measured on a white background, and the colorimetric value was measured on a black background for this composite material having a thickness of 1 mm by a spectral colorimeter. A contrast ratio was obtained by dividing the value Y measured on a black background, by the value Y measured on a white background. The same test was performed for respective composite materials containing different combinations of a fiber material and a mixed liquid of radical polymerizable monomer compounds to obtain the contrast ratio of each combination. The results are shown in Tables 1-1, and 1-2.

Example 1

(7) E-glass fibers (refractive index: 1.558) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 6 mm. S-glass fibers (refractive index: 1.521) were laid on the E-glass fibers in the mold to a height of 6 mm. Mixed liquid A of radical polymerizable monomer compounds was poured in gaps between the E-glass fibers and in gaps between the S-glass fibers. Then, the content of mixed liquid A of radical polymerizable monomer compounds was adjusted so that the total content of the two kinds of fiber materials was 55 wt % and the content of mixed liquid A of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a block-like composite material including two kinds of fiber materials. In this block-like composite material, the transparency of each layer which are located with one fiber material among two different kinds of fiber materials, are different each other. An opacity of a layer (contrast ratio: 0.58) located with the E-glass fiber was higher than that of a layer (contrast ratio: 0.46) located with the S-glass fiber.

Examples 2, 3

(8) Block-like composite materials containing different combinations of a fiber material and a mixed liquid of radical polymerizable monomer compounds were prepared by the same method as in Example 1. The fiber materials and mixed liquids of radical polymerizable monomer compounds used in these Examples are shown in Table. A block-like composite material including two layers having different transparencies were obtained in both Examples 2 and 3.

Examples 4, 5

(9) Block-like composite materials containing different combinations of a fiber material and a mixed liquid of radical polymerizable monomer compounds were prepared by the same method as in Example 1. The fiber materials and mixed liquids of radical polymerizable monomer compounds used in these Examples are shown in Table. In Example 4, the layers containing different fiber materials had a high transparency, and a low contrast of transparency between the layers. In Example 5, the layers containing different fiber materials had a low transparency, and a low contrast of transparency between the layers.

Example 6

(10) ECR-glass fibers (refractive index: 1.570) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 4 mm. E-glass fibers (refractive index: 1.558) were laid on the ECR-glass fibers in the mold to a height of 4 mm and S-glass fibers (refractive index: 1.521) were laid on the E-glass fibers in the mold to a height of 4 mm. Mixed liquid A of radical polymerizable monomer compounds was poured in gaps between the ECR-glass fibers, in gaps between the E-glass fibers, and in gaps between the S-glass fibers. Then, the content of mixed liquid A of radical polymerizable monomer compounds was adjusted so that the total content of the three kinds of fiber materials was 55 wt % and the content of mixed liquid A of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a block-like composite material including three kinds of fiber materials. A transparency of this block-like composite material varied in three steps.

Example 7

(11) ECR-glass fibers (refractive index: 1.570) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 4 mm. AR-glass fibers (refractive index: 1.562) were laid on the ECR-glass fibers in the mold to a height of 2 mm, E-glass fibers (refractive index: 1.558) were laid on the AR-glass fibers in the mold to a height of 2 mm and S-glass fibers (refractive index: 1.521) were laid on the E-glass fibers in the mold to a height of 4 mm. Mixed liquid A of radical polymerizable monomer compounds was poured in gaps between the ECR-glass fibers, in gaps between the AR-glass fibers, in gaps between the E-glass fibers, and in gaps between the S-glass fibers. The content of mixed liquid A of radical polymerizable monomer compounds was adjusted so that the total content of the four kinds of fiber materials was 55 wt % and the content of mixed liquid A of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a block-like composite material including four kinds of fiber materials. A transparency of this block-like composite material varied in four steps.

Example 8

(12) ECR-glass fibers (refractive index: 1.558) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 6 mm. Mixed liquid A of radical polymerizable monomer compounds was poured to the same height as that of laid ECR-glass fibers. Then, in a range to 6 mm, the content of mixed liquid A of radical polymerizable monomer compounds was adjusted so that the content of the ECR-glass fibers was 55 wt % and the content of mixed liquid A of radical polymerizable monomer compounds was 45 wt %. AR-glass fibers (refractive index: 1.562) were laid on this layer in the mold to a height of 6 mm. Mixed liquid C of radical polymerizable monomer compounds was poured in the layer in which the AR-glass fibers were laid. Then, in a range to 6 mm, the content of mixed liquid C of radical polymerizable monomer compounds was adjusted so that the content of the AR-glass fiber was 55 wt % and the content of mixed liquid C of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a block-like composite material. In this block-like composite material, an opacity of a layer (contrast ratio: 0.70) located with the ECR-glass fibers and poured with mixed liquid A of radical polymerizable monomer compounds was higher than that of a layer (contrast ratio: 0.38) located with the AR-glass fibers and poured with mixed liquid C of radical polymerizable monomer compounds.

Example 9

(13) To mixed liquid C of radical polymerizable monomer compounds was added 0.08 wt % of titanium oxide and the titanium oxide was dispersed sufficiently by a mortar to prepare mixed liquid C2 of radical polymerizable monomer compounds. To mixed liquid C of radical polymerizable monomer compounds was added 0.02 wt % of titanium oxide and the titanium oxide was dispersed sufficiently by a mortar to prepare mixed liquid C3 of radical polymerizable monomer compounds. E-glass fibers (refractive index: 1.558) were laid in a rectangular parallelepiped shape mold of 12×14×18 mm to a height of 6 mm. Mixed liquid C2 of radical polymerizable monomer compounds was poured in gaps between the E-glass fibers. Then, in a range to 6 mm, the content of mixed liquid C2 of radical polymerizable monomer compounds was adjusted so that the content of the E-glass fiber was 55 wt % and the content of mixed liquid C2 of radical polymerizable monomer compounds was 45 wt %. E-glass fibers were laid on this layer in the mold to a height of 6 mm. Mixed liquid C3 of radical polymerizable monomer compounds was poured in gaps between the E-glass fibers. Then, in a range to 6 mm, the content of mixed liquid C3 of radical polymerizable monomer compounds was adjusted so that the content of the E-glass fibers was 55 wt % and the content of mixed liquid C3 of radical polymerizable monomer compounds was 45 wt %. The mold was heated to 100° C. to allow thermal polymerization to proceed, thereby obtaining a block-like composite material. This block-like composite material includes two layers having different transparencies. It was confirmed that a contrast ratio of the layer of mixed liquid C2 of radical polymerizable monomer compounds and the E-glass fiber was 0.69, and a contrast ratio of the layer of mixed liquid C3 of radical polymerizable monomer compounds and the E-glass fiber was 0.47, by a preliminary test.

(14) TABLE-US-00001 TABLE 1 Preliminary test 1 Preliminary test 2 Preliminary test 3 Preliminary test 4 Preliminary test 5 Mixed liquid of Mixed liquid A of Mixed liquid A of Mixed liquid B of Mixed liquid B of Mixed liquid A of radical radical radical radical radical radical polymerizable polymerizable polymerizable polymerizable polymerizable polymerizable monomer monomer monomer monomer monomer monomer compounds compounds compounds compounds compounds compounds (Refractive index: (Refractive index: (Refractive (Refractive index: (Refractive index: 1.535) 1.535) index: 1.505) 1.505) 1.535) Fiber material E-glass fiber S-glass fiber E-glass fiber S-glass fiber ECR-glass fiber (Refractive index: (Refractive index: (Refractive index: (Refractive index: (Refractive index: 1.558) 1.521) 1.558) 1.521) 1.570) Contrast ratio 0.58 0.46 0.79 0.49 0.70 Preliminary test 6 Preliminary test 7 Preliminary test 8 Preliminary test 9 Preliminary test 10 Mixed liquid of Mixed liquid C of Mixed liquid C of Mixed liquid B of Mixed liquid B of Mixed liquid A of radical radical radical radical radical radical polymerizable polymerizable polymerizable polymerizable polymerizable polymerizable monomer monomer monomer monomer monomer monomer compounds compounds compounds compounds compounds compounds (Refractive index: (Refractive index: (Refractive index: (Refractive index: (Refractive index: 1.553) 1.553) 1.505) 1.505) 1.535) Fiber material E-glass fiber AR-glass fiber AR-glass fiber ECR-glass fiber AR-glass fiber (Refractive index: (Refractive index: (Refractive index: (Refractive index: (Refractive index: 1.558) 1.562) 1.562) 1.570) 1.562) Contrast ratio 0.31 0.38 0.80 0.89 0.62

(15) TABLE-US-00002 TABLE 2 Example 1 Example 2 Example 3 First layer Mixed liquid A of radical Mixed liquid B of radical Mixed liquid A of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and E-glass fiber E-glass fiber ECR-glass fiber Contrast ratio: 0.58 Contrast ratio: 0.79 Contrast ratio: 0.70 Second layer Mixed liquid A of radical Mixed liquid B of radical Mixed liquid A of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and S-glass fiber S-glass fiber S-glass fiber Contrast ratio: 0.46 Contrast ratio: 0.49 Contrast ratio: 0.46 Example 4 Example 5 Example 6 First layer Mixed liquid C of radical Mixed liquid B of radical Mixed liquid A of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and E-glass fiber AR-glass fiber ECR-glass fiber Contrast ratio: 0.31 Contrast ratio: 0.80 Contrast ratio: 0.70 Second layer Mixed liquid C of radical Mixed liquid B of radical Mixed liquid A of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and AR-glass fiber ECR-glass fiber E-glass fiber Contrast ratio: 0.38 Contrast ratio: 0.89 Contrast ratio: 0.58 Third layer — — Mixed liquid A of radical polymerizable monomer compounds and S-glass fiber Contrast ratio: 0.46 Example 7 Example 8 Example 9 First layer Mixed liquid A of radical Mixed liquid A of radical Mixed liquid C2 of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and ECR-glass fiber ECR-glass fiber E-glass fiber Contrast ratio: 0.70 Contrast ratio: 0.70 Contrast ratio: 0.69 Second layer Mixed liquid A of radical Mixed liquid C of radical Mixed liquid C3 of radical polymerizable monomer polymerizable monomer polymerizable monomer compounds and compounds and compounds and AR-glass fiber AR-glass fiber E-glass fiber Contrast ratio: 0.62 Contrast ratio: 0.38 Contrast ratio: 0.47 Third layer Mixed liquid A of radical — — polymerizable monomer compounds and E-glass fiber Contrast ratio: 0.58 Forth layer Mixed liquid A of radical — — polymerizable monomer compounds and S-glass fiber Contrast ratio: 0.46

INDUSTRIAL APPLICABILITY

(16) A block-like composite material for dental cutting and processing of the present invention may be cut and processed by a dental CAD/CAM system, and may provide a dental prosthesis device (crown, bridge) having both high strength and high esthetics.