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Volume 7 (1988)
- Issue 2 Pages 141-
- Issue 1 Pages 1-
Volume 7, Issue 1
Displaying 1-12 of 12 articles from this issue
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Tadao FUKUSHIMA, Jack L. FERRACANE, Takashi HORIBE, Toru OKABE1988 Volume 7 Issue 1 Pages 1-12,133
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe shear bond strength of the bonding agents, containing 2-succinoxyethyl methacrylate (2SEM) and three succinoxyethyl methacrylate derivatives (2SPrM, SPPM and Bis SGMA), to four polished dental alloys under dry and wet conditions was measured, in order to investigate the relationship between the chemical structure and the decrease of bond strength in water. The bond strength of most of bonding agents was higher than that of controls (BGDMA and acrylic resin) under dry conditions. The bond strength was reduced by immersion in water. The bond strength of most of bonding agents to nonprecious alloys under wet conditions was higher than that of the controls. The average bond strength of 100mol% 2SEM, 100mol% 2SPrM and 30mol% Bis SGMA bonding agents was superior to that of the others. The decrease in bond strength in water may be dependent upon the amount of water sorption of the bonding agents, as well as the magnitude of the stress at the resin-alloy interface. This interface stress may be altered by water sorption.View full abstractDownload PDF (1936K) -
Hiromasa KATO, Kazuo ITOH, Sadao WAKUMOTO1988 Volume 7 Issue 1 Pages 13-18,133
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe bonding ability of bonding agents and composites from three manufacturers, which have both chemically and visible light activated systems, were evaluated by measuring the contraction gap width between the material and the cavity wall in a dentin cavity.
The visible light cured composites were inferior to the same manufacturer's chemically cured composites in marginal adaptation to a cylindrical dentin cavity. However, the adaptation of composites to the cavity wall was improved when the light cured bonding agent was polymerized prior to the placement of chemically cured composite resin.View full abstractDownload PDF (959K) -
Adhesion of MMA/TBB-O Resin to Dentin Improved by 1-35 (MTYA)Tohru HAYAKAWA, Hiroshi ENDO, Tetsuo HARA, Kyoko FUKAI, Kozo HORIE1988 Volume 7 Issue 1 Pages 19-23,133
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe adhesion between MMA/TBB-O resin to dentin treated with 1-35 (MTYA) was investigated. The dentin was etched either with 40% phosphoric acid (H3PO4), 10% citric acid or 10% citric acid-3% FeCl3 (10-3) solution. After the 1-35 (MTYA) treatment, MMA/TBB-O resin was applied to the treated surface. The tensile bond strengths were measured after 1 day in 37°C water.
They were respectively 18MPa for 60s H3PO4 etching, 23MPa for 60s citric acid etching, 20MPa for 30s 10-3 etching, and 16MPa for 60s 10-3 etching. Without the 1-35 (MTYA) treatment, the bond strengths were 0MPa for H3PO4 etching and citric acid etching, and about 5-8MPa for 10-3 etching. The thickness of the resin reinforced dentin was not proportional to the bond strengths.View full abstractDownload PDF (2180K) -
Kouichi WATANABE, Seigo OKAWA, Osamu MIYAKAWA, Syuji NAKANO, Nobuhiro ...1988 Volume 7 Issue 1 Pages 24-38,134
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThin oxide films formed on commercial metal/porcelain Ni-Cr alloy containing Be, were studied by using the electron probe microanalyzer (EPMA) with the glass lining technique and by the X-ray diffraction method with the Debye-Scherrer camera. Oxidation was restricted to form thin oxide films as follows; at 700°C for 5 minutes in air, at 1, 000°C for 2 minutes in air, and at 1, 000°C for 40 minutes in vacuum (10-3 Torr). In the case of oxidation in air, the major oxides were NiO and Cr2O3, and the ratios of Cr2O3 to NiO were 0.57 at 700°C and 2.5 at 1, 000°C. For oxidation in vacuum, only BeO and BeCr2O4 were detected. In all cases, the fine structure of the oxide film was modified in correspondence with the substrate alloy phase. These structural data and morphological data are discussed with respect to the general oxidation theory.View full abstractDownload PDF (8965K) -
Mutsuo YAMAUCHI, Makoto SAKAI, Joji KAWANO1988 Volume 7 Issue 1 Pages 39-47,134
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSPure titanium cast plate denture produced by Ohara's titanium casting system were inserted in eight patients. The pure titanium cast plate dentures enabled satisfactory fitness and had good adaptability to the mucosal surface. Furthermore, they are lighter in weight than conventional cast dentures. X-ray examination revealed some casting defects, but these defects were not serious enough to be conducive to damages. Follow-up observation of the patients with these dentures indicated no clinical problems. However, inadequate adhesiveness with resin was a technical problem encountered. Examination of the castability of pure titanium using this system showed that casting in the meshtype wax pattern failed to produce a complete form of mesh, while casting in the plate-type wax patterns produced a complete contour of the plates. X-ray examination of the plate cast, however, revealed some casting defects.View full abstractDownload PDF (5551K) -
Koichi FUJII, Junichi OKU, Hiroyuki ARIKAWA, Hiroto YAMAUCHI, Hideo OH ...1988 Volume 7 Issue 1 Pages 48-54,134
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSWorking time and setting time of four commercial sealants were investigated by means of a rheometer for composite resins. Temperatures in extracted human tooth were also examined by means of a thermocouple during the setting of sealant brushed into the pit and fissures. In addition, unreacted substances in the cured materials were studied using a high performance liquid chromatography.
The working time was 0.52-1.09min at 23°C and the setting time was 0.91-1.38min at 32°C. The temperature of the dentin at a point 1.20mm from the roof of the pulp chamber ranged from 0.18 to 0.21°C, as specimens of each material 0.5mm thickness were cured. The percentages of unreacted substances were calculated as the ratio of the area under the chromatogram curve obtained before and after curing, and these ranged from 19.7 to 45.8 for specimens of the four materials with a thickness of 0.5mm.
Probably, temperatures during the setting of the four materials tested had little effect on the damage to dental pulp.View full abstractDownload PDF (1802K) -
Part 3 Cytotoxicity Test to Mouse Fibroblasts in Culture of UV and Visible Light-activated Composite ResinsKatsuichiro INOUE, Hiroyuki ARIKAWA, Koichi FUJII, Akira NIIHARA, Ryui ...1988 Volume 7 Issue 1 Pages 55-61,135
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSAgar overlay cytotoxicity tests of 18 commercial light-activated composite resins were carried out, using L929 mouse fibroblasts in culture, and the difference of adverse reaction to L-cell among certain materials was compared. In addition, the unreacted substances in the cured material, such as Bis-GMA and Triethyleneglycol dimethacrylate, were measured using a high performance liquid chromatograph, and the relationship between the amount of unreacted substance and the injured toxic area (cm2) of L-cell was presented and discussed. From the results, with the exception of a few materials, adequate correlation between both factors was estimated. The injured area of L-cell was enlarged as the unreacted substances in the cured material increased.View full abstractDownload PDF (1073K) -
The effect of Resin-Bonded Bridge Design Parameters on Crack Growth along Adhesive LayerNaoyuki SHINOHARA1988 Volume 7 Issue 1 Pages 62-73,135
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe effects of resin-bonded bridge geometry on crack growth along the adhesive layer were analyzed by the use of elastic energy release rate g concept, together with the finite element technique. The values of g and the critical load for crack propagation in the adhesive layer are presented for various horizontal crack length a*, safety factor n, and metal frame configuration and thickness tm. Based on this analysis, suggestions for the design of resin-bonded bridge are suggested, in order to increase its durability.View full abstractDownload PDF (1408K) -
Effect of Calcium and Fluorine AdditionSeiji BAN, Shozo TSURUTA, Tetsuo WATANABE, Motohiko KIKUCHI, Jiro HASE ...1988 Volume 7 Issue 1 Pages 74-86,136
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSZnO-Al2O3 powders containing calcium and fluorine were prepared by the homogeneous co-precipitation method. The effect of the addition of calcium and fluorine on the characteristics of ZnO-Al2O3 powders and the properties of the experimental zinc phosphate cement were examined. The particle size of ZnO increased with increasing amounts of calcium and fluorine, whereas content amounts of ZnO and Al2O3 changed little with the addition of both elements. The properties of the experimental cements showed that compressive strength decreased, the setting time decreased and neutralization on the cement surface accelerated with the addition of both elements. The solubility of the cements in either 1% lactic acid or 1% citric acid was smaller than that of a commercial zinc phosphate cement.View full abstractDownload PDF (2905K) -
Masao IRIE, Hiroyuki NAKAI1988 Volume 7 Issue 1 Pages 87-93,136
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe mechanical properties of glass ionomers, with and without silver addition, for manual mixing and for mechanical mixing, were examined using commercial products. The shear bond strength of the same materials to non-treated human tooth was also examined. The mechanical properties and bond strength of silver-added materials were significantly lower than those of conventional ones. The bond strength to dentin was similar regardless of the addition of silver; however, that to enamel was statistically lower with silver-added materials. No significant difference was observed between the materials for manual mixing and mechanical mixing, whether the material was silver-added or not. The bond strength correlated highly with diametral tensile and flexural strength, but the compressive strength did not have such a relationship.View full abstractDownload PDF (1398K) -
Michihiko TAKEYA, Nobushige MURAKAMI, Masako UNEMORI, Masako MOTOMURA, ...1988 Volume 7 Issue 1 Pages 94-110,136
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSComparisons of simple surface preparation of the dental Au-Ag-Pd alloy for improving the adhesion to 4-META/MMA-TBB resin cement were carried out by bonding metal to metal and metal to the etched enamel.
The anodized surface with phosphoric acid after sandblasting kept sufficient bond strengths during immersion in water at 37°C for three months, whereas that after cleansing showed a marked decrease in bond strengths during immersing times from one up to three months. Bond strengths of the surface only sandblasted were low in the early stage of water immersion but increased during immersing times from one up to three months.
It appeared that 4-META/MMA-TBB resin cement continuously formed new adhesion even during immersion in water.View full abstractDownload PDF (8778K) -
YOSHIO KOZONO, M. Eng., D.D. Sc.1988 Volume 7 Issue 1 Pages 111-118
Published: June 25, 1988
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSDownload PDF (863K)
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