Abstract: Provided is a dental floss that keeps cleaning performance thereof on one hand, and that is easy to handle because of a high rigid portion thereof on the other hand. Dental floss includes: a floss part that is formed by twisting a plurality of filaments together but not tying up the filaments; and tied-up parts that are provided continuously with the floss part, and are formed by tying up the plurality of the filaments, wherein each of the tied-up parts is formed in such a manner that filaments are covered with a contour part in a cross section thereof.

Abstract: To provide a bone tissue regeneration sheet having a cortical bone tissue layer of 200 ?m or more in thickness, the bone tissue regeneration sheet is produced by seeding chondroblast or stem cells for differentiating to chondrocyte on one side of a porous bioabsorbable polymer sheet, taking the seeded porous body into a culture medium, applying centrifugal force of 100 to 1000 G to the culture medium for a predetermined time so as to aggregate the chondroblast or the stem cells for differentiating to chondrocyte, culturing the aggregated cells in a culture medium not containing serum but containing one or two or more kinds selected from ascorbic acid, an ascorbic acid derivative, and dexamethasone without applying centrifugal force to form a chondrocyte layer having a thickness of 200 ?m or more.

Abstract: For easily seeding cells in its scaffold, a porous cell scaffold is produced by steps of filling a guiding solution with kinematic viscosity being 50 to 450% of that of a culture medium, in a whole continuous small hole structure having hole diameters of 5 to 3200 ?m and an average hole diameter of 50 to 1500 ?m, of a sheet-shaped or block-shaped scaffold having a thickness of 2 mm or more, supplying thereafter a culture medium with cells being suspended to an upper side of the scaffold, sucking the guiding solution from a lower side of the scaffold by low suction force, and entering thereby the culture medium with cells being suspended into the whole small hole structure, where a water absorber such as a filter paper is preferably used for sucking the guiding solution by low suction force.

Abstract: A block-shaped scaffold for a tissue engineering with improved shape stability and less volume change in water is produce by the steps of approximate-uniformly mixing the particle-shaped material having 100 to 2000 ?m diameter with a solution, where a biodegradable polymer is dissolved with an organic solvent, freezing, drying it to remove the solvent, pulverizing thus obtained intermediate product, dissolving it with a liquid, where the biodegradable polymer is not dissolved, to remove the particle-shaped material taking thus obtained intermediate product into a mold, and pressing and heating it, the scaffold having ununiform and continuous holes occupying 20 to 80% in a cross-section area in a three-dimensional network structure having a small hole structure with 5 to 50 ?m diameter, elastic coefficient being 0.1 to 2.5 MPa, and volume change being 95 to 105% when dipping it in water for 24 hours.

Abstract: To provide a bone graft substitute having an appropriate absorption period in a living body and high osteoconductivity, the bone graft substitute contains a carbonate apatite and an osteoinductive factor, the osteoinductive factor is preferably at least one kind selected from a group including BMP (a bone morphogenetic protein), GDF (a growth differentiation factor), TGF-? (a transformation growth factor), FGF (a fibroblast growth factor), IGF (an insulin-like growth factor), PDGF (a platelet-derived growth factor), BDNF (a brain-derived nerve growth factor), and NGF (a nerve growth factor), and the bone graft substitute has open pores, preferably having a diameter of 50 to 1000 ?m and/or a diameter of 0.001 to 5 ?m, with porosity of 20 to 80%.

Abstract: A block-shaped scaffold for a tissue engineering with improved shape stability and less volume change in water is produce by the steps of approximate-uniformly mixing the particle-shaped material having 100 to 2000 ?m diameter with a solution, where a biodegradable polymer is dissolved with an organic solvent, freezing, drying it to remove the solvent, pulverizing thus obtained intermediate product, dissolving it with a liquid, where the biodegradable polymer is not dissolved, to remove the particle-shaped material taking thus obtained intermediate product into a mold, and pressing and heating it, the scaffold having ununiform and continuous holes occupying 20 to 80% in a cross-section area in a three-dimensional network structure having a small hole structure with 5 to 50 ?m diameter, elastic coefficient being 0.1 to 2.5 MPa, and volume change being 95 to 105% when dipping it in water for 24 hours.

Abstract: To provide a scaffold for tissue engineering which consists of a bioabsorbable polymer material to be absorbed in a biotissue, and holds strength of the whole scaffold while having a porosity proper for culturing cells inside thereof as well, a method for producing the scaffold for tissue engineering includes steps of dissolving a bioabsorbable polymer material with an organic solvent, drying the solution so as to produce a porous bioabsorbable polymer material having a porosity of 50 to 99%, covering the porous bioabsorbable polymer material with a bioabsorbable polymer material having a thickness of 0.01 to 5 mm, pores of 10 to 3000 ?m diameter, a fracture strength of 0.05 to 0.15 MPa, and a volume of 15 to 90% with respect to the whole scaffold.

Abstract: To provide a bone tissue regeneration sheet having a cortical bone tissue layer of 200 ?m or more in thickness, the bone tissue regeneration sheet is produced by seeding chondroblast or stem cells for differentiating to chondrocyte on one side of a porous bioabsorbable polymer sheet, taking the seeded porous body into a culture medium, applying centrifugal force of 100 to 1000 G to the culture medium for a predetermined time so as to aggregate the chondroblast or the stem cells for differentiating to chondrocyte, culturing the aggregated cells in a culture medium not containing serum but containing one or two or more kinds selected from ascorbic acid, an ascorbic acid derivative, and dexamethasone without applying centrifugal force to form a chondrocyte layer having a thickness of 200 ?m or more.

Abstract: For easily seeding cells in its scaffold, a porous cell scaffold is produced by steps of filling a guiding solution with kinematic viscosity being 50 to 450% of that of a culture medium, in a whole continuous small hole structure having hole diameters of 5 to 3200 ?m and an average hole diameter of 50 to 1500 ?m, of a sheet-shaped or block-shaped scaffold having a thickness of 2 mm or more, supplying thereafter a culture medium with cells being suspended to an upper side of the scaffold, sucking the guiding solution from a lower side of the scaffold by low suction force, and entering thereby the culture medium with cells being suspended into the whole small hole structure, where a water absorber such as a filter paper is preferably used for sucking the guiding solution by low suction force.

Abstract: To provide an organism absorbency tube for regenerating nerve tissue and a production method thereof, where the low cost tube can produce easier than a conventional one, various kinds of the different thickness tubes, inner diameters and outer shapes can be easily formed. The tube produces by drying polymer solvent to form sheet-like organism absorbency polymer material; cylindrically rolling thus material to form an overlapped sheet part; heat or solvent meld sealing at least a portion around an end edge on the outer peripheral side thereof. Or a two layers structure tube produces by freeze-drying polymer solvent to form the material; cylindrically rolling thus material; non-freeze-drying polymer solvent to form the high material; cylindrically wrapping thus material around the freeze-dried polymer material to form the sheet part; and heat or solvent meld sealing at least a portion around an edge on the outer peripheral side thereof.

Abstract: A block-shaped scaffold for a tissue engineering with improved shape stability and less volume change in water is produce by the steps of approximate-uniformly mixing the particle-shaped material having 100 to 2000 ?m diameter with a solution, where a biodegradable polymer is dissolved with an organic solvent, freezing, drying it to remove the solvent, pulverizing thus obtained intermediate product, dissolving it with a liquid, where the biodegradable polymer is not dissolved, to remove the particle-shaped material taking thus obtained intermediate product into a mold, and pressing and heating it, the scaffold having ununiform and continuous holes occupying 20 to 80% in a cross-section area in a three-dimensional network structure having a small hole structure with 5 to 50 ?m diameter, elastic coefficient being 0.1 to 2.5 MPa, and volume change being 95 to 105% when dipping it in water for 24 hours.

Abstract: A bioabsorbable granular porous bone filling material having a particle diameter 100 to 3000 ?m used for filling a defect part after removing a lesion, or grafting a self bone, and for reinforcing or filling a jawbone when embedding a dental implant, is produced such that the polymer material containing a particle-shaped material and having the small hole structure with the hole diameter of 5 to 50 ?m is made by mixing the particle-shaped material having a diameter of 100 to 2000 ?m with a solution, where the bioabsorbable polymer is dissolved with an organic solvent, the particle-shaped material being not dissolved with this organic solvent but dissolved with a liquid not dissolving the bioabsorbable polymer, freezing it, drying it to remove the organic solvent, pulverizing the produced material, dissolving the particle-shaped material with the liquid to be removed, and sieving it.