Publications by authors named "Manamu Nagakura"

Removable partial dentures (RPDs) with resin-clasp retentive parts, which are known as non-metal-clasp dentures (NMCDs), have been used as alternatives for conventional RPDs with metal clasp, in case of aesthetic prosthodontic treatments. In this study, a profilometer and dynamic micro-indentation tests were used to investigate the effects of polishing on the surface properties such as surface roughness (Ra), dynamic hardness, and elastic modulus of high-rigidity glass-fiber-reinforced thermoplastics (GFRTPs) composed of E-glass fibers and polypropylene for NMCDs. The Ra values of the GFRTPs after polishing were significantly lower than those before polishing.

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Purpose: The purpose of this study was to investigate the combined effects of fiber loading and pigmentation on the color differences and flexural properties of glass fiber-reinforced thermoplastics (GFRTPs), for use in non-metal clasp dentures (NMCDs).

Methods: The GFRTPs consisted mainly of E-glass fibers, a polypropylene matrix, and a coloring pigment: the GFRTPs with various fiber loadings (0, 10, and 20mass%) and pigmentations (0, 1, 2, and 4mass%) were fabricated by using an injection molding. The color differences of GFRTPs were measured based on the Commission Internationale de l'Eclairage (CIE) Lab color system, by comparing with a commercially available NMCD.

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Purpose: The purpose of this study was to investigate the color stability of a glass-fiber-reinforced thermoplastic (GFRTP), for use in non-metal clasp dentures (NMCDs).

Methods: GFRTPs composed of E-glass fibers and polypropylene with 2 mass% of pigments were fabricated using injection molding. According to our previous study on the optimum fiber content for GFRTPs, we prepared GFRTPs with fiber contents of 0, 10, and 20 mass% (GF0, GF10, and GF20).

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The use of non-metal clasp denture (NMCD) materials may seriously affect the remaining tissues because of the low rigidity of NMCD materials such as polyamides. The purpose of this study was to develop a high-rigidity glass fiber-reinforced thermoplastic (GFRTP) composed of E-glass fiber and polyamide-6 for NMCDs using an injection molding. The reinforcing effects of fiber on the flexural properties of GFRTPs were investigated using glass fiber content ranging from 0 to 50 mass%.

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Recently, non-metal-clasp dentures (NMCDs) made from thermoplastic resins such as polyamide, polyester, polycarbonate, and polypropylene have been used as removable partial dentures (RPDs). However, the use of such RPDs can seriously affect various tissues because of their low rigidity. In this study, we fabricated high-rigidity glass-fiber-reinforced thermoplastics (GFRTPs) for use in RPDs, and examined their physical properties such as apparent density, dynamic hardness, and flexural properties.

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Purpose: The purpose of this article is to review the mechanical requirements of the tissue-implant interface and analyze related theories.

Study Selection: The osseointegration capacity of titanium implants has been investigated over the past 50 years. We considered the ultimate goal of osseointegration to which form a desirable interfacial layer and a bone matrix with adequate biomechanical properties.

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