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Cumhur SIPAHI, Mutlu ÖZCAN
2012 Volume 31 Issue 3 Pages
333-337
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
JOURNAL
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This study compared the bond strength between metal alloys and 5 ceramic systems. Ceramic systems (Vita VMK68, Ivoclar IPSd. SIGN, Ceramco II, Matchmaker and Finesse) were fired onto either Ni-Cr or Co-Cr base metal alloy. Metal-ceramic interfaces were subjected to shear loading until failure. The ceramic type significantly affected the bond strength results (
p<0.05). For Ni-Cr alloy, the results ranged between 15.4–25.3 MPa and for Co-Cr alloy between 13.3–19.0 MPa. The highest mean bond strength value was obtained with the combination of Ni-Cr alloy-Ceramco II (25.3 MPa), the lowest bond strength was received from the combination of Co-Cr alloy-Ivoclar IPS d.SIGN ceramic (13.3 MPa). Adhesive failures between metal and ceramic were significantly more frequent with Ni-Cr alloy (31 out of 50) than with Co-Cr (20 out of 50) (
p<0.05). Ceramco II presented the highest bond strength with both Ni-Cr and Co-Cr being significantly different from one another.
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Matthias KARL, Friedrich GRAEF, Manfred WICHMANN, Nina BECK
2012 Volume 31 Issue 3 Pages
338-345
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The effect of ceramic veneering on the passivity of fit of cast metal and CAD/CAM-fabricated zirconia ceramic implant-supported three-unit cement-retained restorations was investigated, as well as the effect of misfit stress on the marginal integrity of ceramic veneers. Superstructures were fabricated using cast metal or by CAD/CAM milling of presintered or HIP zirconia ceramic (
n=10). Before and after veneering, strain gages were used to measure
in vitro the strain developed in all the restorations as a result of superstructure fixation. Fluorescent penetrant method was used to detect microcracks developed in ceramic veneers. Cast frameworks showed significantly higher strain values than CAD/CAM frameworks (
p=0.000). Veneering significantly increased strain development in all CAD/CAM frameworks (
p=0.000). Compared to zirconia ceramic restorations, significantly more microcracks were observed in cast restorations (
p=0.000) both before and after superstructure fixation.
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Yutaka KIMURA, Kenichi MATSUZAKA, Masao YOSHINARI, Takashi INOUE
2012 Volume 31 Issue 3 Pages
346-353
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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Initial attachment of human oral keratinocytes (HOKs) cultured on mirror-surfaced commercially pure titanium (Ti) or yttria-stabilized tetragonal zirconia polycrystals (TZP) was investigated. Numbers of viable attached HOKs, their mRNAs and proteins expression of laminin
γ2 and integrin
β4 were evaluated using the WST-1 assay, quantitative real-time PCR and enzyme-linked immunosorbent assay, respectively. Localization of laminin
γ2 and integrin
β4 was observed using immunofluorescent staining. Cell spreading was evaluated by measuring the perimeter of actin on fluorescent stained images, and cell morphology was examined using scanning electron microscopy. At 1 h TZP elicited less of initial attachment than Ti in terms of mRNAs expression and proteins expression of laminin
γ2 and integrin
β4 (
p<0.05). However, at 48 h TZP was showed similar initial attachment in comparison to Ti. Therefore, it was suggested that TZP has a potential to form epithelial attachment like Ti.
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Mohammed Q. AlQAHTANI, Rana M. AlJURAIS, Maan M. AlSHAAFI
2012 Volume 31 Issue 3 Pages
354-361
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The purpose of this study was to quantitatively evaluate the effects of different shades of light-polymerized resin cement on the color of two different thicknesses (0.5 mm and 0.7 mm) of three different ceramic materials (Esthetic, e.max, and ZirPress). A spectrophotometer (Color Eye 7000A - CIE (
L*a*b*) was used to measure the color of specimens on the control substrate without cement, and then on (Translucent, White Opaque, B0.5, A1, and A3 of RelyX™ Veneer cement). The mean values of color difference (
ΔE) were higher for Esthetic, followed by ZirPress, with the lowest values for e.max. The mean values of
ΔE decreased when the thickness of ceramic increased from 0.5 mm to 0.7 mm. It was observed that the White Opaque had significantly increased
ΔE values when compared with (TR, B0.5, A1, and A3), whereas no significant difference between B0.5 and TR, and between B0.5 and A3.
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Md.Sofiqul ISLAM, Noriko HIRAISHI, Mohannad NASSAR, Ryohei SONO, Masay ...
2012 Volume 31 Issue 3 Pages
362-367
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The aims of this study were to investigate the effects of hesperidin, a citrus flavonoid, on human root dentin demineralization and collagen preservation, and compare it with chlorhexidine and grape seed extract. Specimens were assigned to different treatment groups: hesperidin, chlorhexidine and grape seed extract. Specimens were subjected to pH cycling by demineralization for 14 h, incubation in testing solutions for 2 h and remineralization in presence of bacterial-derived collagenase for 8 h, for 8 days. Calcium release was measured by means of an atomic absorption spectrophotometer, and degraded collagen matrix was investigated by hydroxyproline assay. Specimens were assessed longitudinally with transverse micro-radiography to investigate lesion depth and mineral loss. In hesperidin and grape seed extract groups, demineralization was reduced when the collagen matrix was preserved. The hesperidin group showed the lowest value in lesion depth and mineral loss, indicating that hesperidin inhibited demineralization and probably enhanced remineralization even under fluoride-free conditions.
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Atsushi KUWABARA, Norio HORI, Tomofumi SAWADA, Noriyuki HOSHI, Akira W ...
2012 Volume 31 Issue 3 Pages
368-376
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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We investigated whether surface roughness and control of surface electric charge of a hydroxyapatite (HA)/titanium oxide (TiO
2) hybrid coating could enhance biological responses associated with bone formation. After acid etching, a titanium surface was modified with HA and TiO
2 by the dual sputtering deposition technique using radiofrequency sputtering. These surfaces were analyzed for surface roughness and surface electric charge intensity. Rat bone marrow-derived osteoblast-like cells were cultured on HA/TiO
2 hybrid surfaces with different electric charges. The attachment and spreading behavior of these cells were significantly increased on the hybrid surface (
p<0.05).
In vivo experiment, the strength of bone-titanium implant integration with a hybrid surface was 3 times that of a control (
p<0.05). The dual sputtering deposition technique created a HA/TiO
2 hybrid structure. Our results show that the surface electric charge on a titanium surface is an important factor for enhancing biological responses.
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Bogna STAWARCZYK, Beatrice SENER, Albert TROTTMANN, Malgorzata ROOS, M ...
2012 Volume 31 Issue 3 Pages
377-383
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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This study determined the discoloration of five CAD/CAM resins, four manually polymerized resins, and glass-ceramic as control group. Specimens were divided into three groups (
N=300,
n=30) to be stored in coffee, black tea and red wine (
n=10). The discoloration was measured using a spectrophotometer after 1, 7, 29, 90, 180 days storage. All tested groups showed color change (
ΔE) at all time points. The manually polymerized resin composites GD (Gradia) and CM (CronMix K), and the CAD/CAM resin composite HC (Blanc High-class) showed significantly higher
ΔE compared to all other groups in all tested media. The discoloration was extrinsic and decreased after polishing for the majority of the tested materials. Except CAD/CAM resin HC (Blanc High-class), all CAD/CAM resins showed similar color stability compared to the control group.
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Fucong TIAN, Adrian U Jin YAP, Xiaoyan WANG, Xuejun GAO
2012 Volume 31 Issue 3 Pages
384-388
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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This study investigated the color stability of pre-reacted glass-ionomer containing composite restoratives. The materials evaluated included one regular (Beautifil II [BF]), two flowable (Beautifil Flow [F02, F10]) and two recently introduced flowable “plus” (Beautifil Flow Plus [F00, F03]) pre-reacted glass-ionomer containing composite restoratives. Twelve specimens of each material (A3 shade) were fabricated, allowed to set for 24 h at 37°C and randomly divided into 4 groups. After baseline spectrophotometric (Crystaleye, Olympus) color measurements, specimens were immersed in water, cola, red wine and coffee for 7 days. Post-immersion color measurements were taken and color changes (
ΔE) were computed accordingly. Statistical analysis was done using ANOVA and post-hoc Scheffe’s test (
p<0.05). For pre-reacted glass-ionomer containing composites, color changes after immersion in coffee and red wine were significantly greater than in cola and water. Differences in
ΔE values between materials were solution dependent. The least color change was generally observed with the flowable “plus” pre-reacted glass-ionomer containing composites.
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Ahmed JAMLEH, Chihiro KOBAYASHI, Yoshio YAHATA, Arata EBIHARA, Hideaki ...
2012 Volume 31 Issue 3 Pages
389-393
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The dispersion of the lifetime of NiTi instruments, and their deflecting load (DL) changes during cyclic fatigue were investigated. A total of 120 ProFile NiTi rotary instruments were tested using a specially designed cyclic fatigue testing apparatus with three pins. Using these pins, the instrument was bent and rotated at 300 rpm to fracture. DL was recorded using a load cell attached to the central pin. For each sample, the working time was converted to number of cycles to fracture (NCF) and the mean DL (DL
m) was calculated. The averages of NCF and DL
m of 120 samples were 584.3±180.5 cycles and 6.44±0.91 N, respectively. All samples showed a sequential decrease in DL during rotation. Based on the present study, it is impossible to estimate the lifetime of a NiTi instrument from NCF. Thus, the change in DL could be an alternative criterion to determine the remaining lifetime.
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Amir NAZARI, Yasushi SHIMADA, Alireza SADR, Junji TAGAMI
2012 Volume 31 Issue 3 Pages
394-400
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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This study was aimed to determine the effectiveness of grinding and pre-etching in promotion of adhesion to human intact enamel using the self-etch adhesive (SEA) Adper Easy Bond (3M ESPE). Etch-and-rinse adhesive Adper Single Bond (3M ESPE) served as control. Composite cylinders (AP-X Kuraray) were built and after 24 h micro-shear bond strengths (MSBS) were measured. Bonding interfaces were evaluated under scanning electron microscope (SEM). For evaluation of average roughness (Ra) and morphological analysis, treated enamel surfaces were observed under SEM and confocal laser scanning microscope (CLSM) with 3D surface profiling. Highest bond strengths were obtained by pre-etching and grinding showed a less significant role. Phosphoric acid (PA) etching compare to grinding created significantly rougher surface (Ra: 0.72 and 0.43 μm respectively). Therefore, this study recommends pre-etching the intact enamel prior to application of the adhesive instead of grinding.
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Cem SAHIN, Zafer C. CEHRELI, Muhittin YENIGUL, Bulent DAYANGAC
2012 Volume 31 Issue 3 Pages
401-408
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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To investigate the permeability of deep dentin following immediate sealing with different etch-and-rinse and self-etch adhesives (Single Bond 2, Adper Prompt L-Pop, Clearfil Protect Bond, Clearfil S3 Bond, G-Bond) and a dentin desensitizer (Gluma). Fluid-transport model was used to measure fluid conductance during and after application of adhesives. Polyvinylsiloxane impressions of bonded dentin were taken to monitor fluid transudation from the surface of the adhesives. The area and number of dentinal fluid droplets and/or blisters were calculated using image analysis. None of the adhesives were able to block fluid conductance completely. The fluid conductance values of the adhesives displayed the following statistical ranking (
p<0.05): G-Bond≤Clearfil Protect Bond<Smear-layer-covered dentin<S
3 Bond≤Single Bond 2≤Adper Prompt L-Pop<Gluma Desensitizer<Acid-etched dentin. Highly significant correlation was observed between the permeability of the tested adhesives and the area fraction of fluid droplets/blisters on the adhesive surfaces (
r=0.99,
p<0.01).
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Yasushi SHIMADA, Alireza SADR, Amir NAZARI, Hisaichi NAKAGAWA, Masayuk ...
2012 Volume 31 Issue 3 Pages
409-417
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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Internal adaptation of restorations to the cavity wall is one of the important topics in clinical dentistry. The purpose of this study was to investigate the possibility to utilize the non-invasive tomographic imaging system for teaching the importance of cavity adaptation at dental school pre-clinical training. Swept-source optical coherence tomography (SS-OCT) was used for detection of marginal and internal defects in the composite resin restorations as an educational device. Class 1 and Class 2 composite restorations to melamine resin molar tooth were assigned to the students and prepared during the skill test, and SS-OCT imaging was performed to evaluate students’ works. SS-OCT could detect the internal gaps and voids within the restorations in tomography images synthesized based on the backscatter signal from within the restoration. It is suggested that the SS-OCT is promising diagnostic modality, as well as educational imaging device for the detection of internal gaps in adhesive restorations.
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Atsushi MINE, Jan DE DE MUNCK, Marcio V. CARDOSO, Kirsten L. VAN LANDU ...
2012 Volume 31 Issue 3 Pages
418-426
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The purpose of this study was to evaluate if a low-shrinking composite can improve the bonding effectiveness of adhesives in highly constrained conditions. A low-shrinking composite (‘els-extra low shrinkage’, Saremco) was bonded in standardized occlusal Class-I cavities using a three-step (‘cmf’, Saremco) and a two-step etch-and-rinse adhesive (‘XP Bond’, Dentsply). Both adhesives were also combined with a conventional composite (‘Z100’, 3M ESPE). Half of the restored cavities were exposed to 20,000 thermo-cycles. 3-way ANOVA revealed a significant effect for the factors ‘adhesive’ and ‘composite’ (both
p<0.0001), but not for ‘thermo-cycling’ (
p=0.994). Significantly higher bond strengths were recorded for the low-shrinking composite than for the control composite, using either of the adhesives. The low-shrinking composite in combination with the three-step etch-and-rinse adhesive performed best in the high C-factor Class-I cavity. The two-step etch-and-rinse adhesive suffered strongly from polymerization-shrinkage stress, which could be partially restored by using the low-shrinking composite.
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Koichi YAMAKI, Yu KATAOKA, Fukunaga OHTSUKA, Takashi MIYAZAKI
2012 Volume 31 Issue 3 Pages
427-432
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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Titanium surfaces processed by wire-type electric discharge machining (EDM) are microfabricated surfaces with an irregular morphology, and they exhibited excellent
in vitro bone biocompatibility. In this study, the efficiency of
in vivo osteogenesis on EDM surfaces was investigated by surgically placing screw-shaped EDM-processed and machined-surface implants into the femurs of four Japanese white rabbits. The volume and process of new bone formation were evaluated by an X-ray micro-CT scanner, coupled with histopathological observations at 1, 2, and 4 weeks post-implantation. Before surgical implantation, the surface topography and contact angle of each implant surface were examined. Bone formation increased over time on both implant surfaces, with both implant types yielding statistically equivalent bone volume at 4 weeks post-implementation. However, at 1 week post-implantation, amount of new bone at EDM-processed implant was markedly greater than that at machined-surface implant. Moreover, new bone appeared to initiate directly from the EDM surfaces, while new bone appeared to generate from pre-existing host bone to the machined surfaces. Thus, EDM seemed to be a promising method for surface modification of titanium implants to support enhanced osteogenesis.
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Hao YU, Wolfgang BUCHALLA, Hui CHENG, Annette WIEGAND, Thomas ATTIN
2012 Volume 31 Issue 3 Pages
433-442
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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This study aimed to investigate the effect of topical fluoride application on the acid susceptibility of restorative materials. Four restorative materials were investigated in this study: 2 composite resins (Tetric EvoCeram and Filtek Silorane), a polyacid-modified resin composite (Dyract Extra), and a conventional glass-ionomer cement (Ketac Fil Plus). The samples were treated once with 1 of 8 different fluoride solutions (TiF
4, NaF, AmF, and SnF
2, each at native pH or pH 4) for 3 min or remained untreated (control). The samples were then eroded by citric acid (pH 2.6) for 5 days (6×1 min daily). Erosive substance loss, surface topographic and compositional changes were investigated using surface profilometry, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), respectively, after fluoride pretreatment and after erosion. The results indicate high-concentrated AmF solution at native pH was effective in inhibiting erosion in the conventional glass-ionomer cement and polyacid-modified resin composite.
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Ken ODAGIRI, Tomofumi SAWADA, Norio HORI, Kazuhide SEIMIYA, Takeshi OT ...
2012 Volume 31 Issue 3 Pages
443-448
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The effects of certain disinfectants on the stability of a polymethyl methacrylate denture base resin were investigated, including those of a novel disinfection method using reactive oxygen species (ROS). The surface roughness and flexural strength were analyzed to assess the effects of the disinfectants on material properties. The following disinfectants were tested: 5% sodium hypochlorite, 70% alcohol, and ROS. Furthermore, the attachment of
Candida albicans to the resin surface was investigated. The disinfection method using sodium hypochlorite significantly increased the surface roughness and decreased flexural strength. The surface roughness and flexural strength of the ROS-treated specimens did not significantly differ from those of the control specimens, and the ROS-treated specimens exhibited diminished
Candida attachment. These results demonstrate that the ROS disinfection method preserves acceptable material stability levels in polymethyl methacrylate resins.
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Soichi KURODA, Daiichiro YOKOYAMA, Akikazu SHINYA, Harunori GOMI, Akiy ...
2012 Volume 31 Issue 3 Pages
449-457
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The present study was designed to measure the durability of glass fiber-reinforced hybrid resins (FRC) in clinical applications. Accordingly, we studied the effects of static and dynamic loading as well as temperature changes inside the oral cavity, a moist environment, on the bending strength of FRC. The bending strength was measured using several tests, including an open-air bending strength test (AE), a 24-h water immersion test (WC1D), a 2-year water immersion test (WC2Y), a thermal cycling test (TC), a repeated in-water impact test at 37°C/10
5 (WI37), and a repeated in-water impact test at 55°C/10
5 (WI55). The following tests are ordered from greatest to least with respect to GF’s bending strength: AE, WI37, WI55, WC1D, WC2Y, and TC. Likewise, the following tests are ordered from greatest to least with respect to EV’s bending strength: AE, WC1D, WC2Y, WI37, WI55, and TC.
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Makiko SAITA, Kyou KOBATASHI, Fumihiko YOSHINO, Hiriko HASE, Toru NONA ...
2012 Volume 31 Issue 3 Pages
458-464
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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It is well known that clinical bleaching can be achieved with a solution of 30% hydrogen peroxide (H
2O
2) or H
2O
2/titanium dioxide (TiO
2) combination. This study examined the hypothesis that TiO
2 coated with hydroxyapatite (HAp-TiO
2) can generate reactive oxygen species (ROS). ROS are generated
via photocatalysis using electron spin resonance (ESR). The bleaching properties of HAp-TiO
2 in the presence of H
2O
2 can be measured using hematoporphyrin litmus paper and extracted teeth. We demonstrate that superoxides (O
2•−) and hydroxyl radicals (HO
•) can be generated through excitation of anatase TiO
2, rutile TiO
2, anatase HAp-TiO
2, and rutile HAp-TiO
2 in the presence of H
2O
2. The combination of R HAp-TiO
2 with H
2O
2 produced the highest level of HO
• generation and the most marked bleaching effects of all the samples. The superior bleaching effects exhibited by R HAp-TiO
2 with H
2O
2 suggest that this combination may lead to novel methods for the clinical application of bleaching treatments.
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Masaaki TAKECHI, Koji OHTA, Yoshiaki NINOMIYA, Misato TADA, Masayuki M ...
2012 Volume 31 Issue 3 Pages
465-471
Published: 2012
Released on J-STAGE: May 28, 2012
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We fabricated 3-dimensional scaffolds consisting of biodegradable poly(D, L-lactide-co-glycolic acid)(PLGA)(75/25) with hydroxyapatite particles containing atelocollagen (aAC). The aim of this study was to evaluate this new type of scaffold in regard to its basic properties and biocompatibility. Characterization of the obtained scaffolds was performed to know the porosity, shrinkage, diametral tensile strength, and biocompatibility. Composite scaffolds made of PLGA with hydroxyapatite particles containing atelocollagen (PL-aAC) showed a greater strength and stability than PLGA scaffolds. PL-aAC also exhibited superior performance in terms of cell attachment and proliferation as compared to PLGA, while histological findings showed that PL-aAC had an excellent response toward soft tissues. Our results strongly suggest that PL-aAC is more useful for cell transplantation as compared to PLGA for bone tissue engineering.
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Hiroaki YAMAGUCHI, Satoshi INO, Naho HAMANO, Shusaku OKADA, Toshio TER ...
2012 Volume 31 Issue 3 Pages
472-480
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The purpose of our study was to evaluate the effects of surface modifications on the bond strength between veneering porcelains and Yttria-stabilized tetragonal zirconia (Y-TZP). In a bond strength tests, the effect of control, 70 μm alumina-sandblasting, 30 μm and 110 μm silica-coating of the Y-TZP surface on bonding were evaluated with veneering porcelains. In addition, the effect of surface modification on the flexural strength of Y-TZP was also evaluated. The data was analyzed using one-way ANOVA and Tukey test. All specimens showed bond strength values in excess of 25 MPa, the minimum allowed by ISO9693. In addition, significantly differences were found between the control and the 30 μm silica-coated. On the other hand the flexural strength of Y-TZP does not significantly difference for any surface modification. These results indicate that silica-coating may provide an effective pre-treatment for this enhancement of the bond strength while maintaining the strength of Y-TZP.
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Chika YAHAGI, Tomohiro TAKAGAKI, Alireza SADR, Masaomi IKEDA, Toru NIK ...
2012 Volume 31 Issue 3 Pages
481-488
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The purpose of this study was to evaluate the effect of lining with a flowable composite on internal adaptation of composite restorations using three all-in-one adhesive systems; Bond Force (BF), G-Bond Plus (GP), and OptiBond All-in-one (OP), and a two-step self-etching adhesive system; Clearfil SE Bond (SE). They were applied to each cylindrical cavity prepared on the human dentin. The cavity surface was lined with/without a flowable resin composite prior to filling with a resin composite (FL/NL). After water storage for 24 h, the specimens were sectioned and polished, and internal adaptation of the restorations was assessed using a confocal laser scanning microscopy. For SE, a perfect cavity adaptation was recognized in both FL and NL. For BF, GP and OP, cavity adaptation was material dependent in NL, whereas no gap formation was observed in FL. However, voids formation was observed at the composite-adhesive-dentin interface in every all-in-one adhesive system.
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Koji TANABE, Hideki NOMOTO, Naoto OKUMORI, Tadashi MIURA, Masao YOSHIN ...
2012 Volume 31 Issue 3 Pages
489-493
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The aim was to investigate the local osteogenic effect of fluvastatin incorporated into a biodegradable gelatin-hydrogel (GH) scaffold. The GH scaffolds were prepared through crosslinking by ultraviolet irradiation followed by freeze-drying. Two circular defects were surgically created on fifteen-week-old male rats calvaria. All defects of each rat were randomly filled with two of three treatments, specifically: fluvastatin incorporated into a GH disk (Flu-GH), distilled water incorporated into a GH disk, and no treatment. New bone formation was quantitatively analyzed after 7, 14, and 28 days using a micro-computed tomography (micro-CT) system, and histologically observed. Evaluation by micro-CT revealed a significant difference in new bone formation among the three kinds of defect. A highly osteogenic effect was observed in the Flu-GH group. The results showed that the fluvastatin incorporated into a biodegradable GH scaffold promoted osteogenesis in rat calvarial bone, indicating its potential for bone regeneration.
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Xin WU, Masafumi NAKAGAWA, Fumio TERAOKA
2012 Volume 31 Issue 3 Pages
494-498
Published: 2012
Released on J-STAGE: May 28, 2012
Advance online publication: May 14, 2012
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The aim of this study is to investigate the internal morphology of all-ceramic prostheses before seating. Micro X-ray CT was used to inspect three dimensionally the locations and sizes of pores within experimentally fabricated all-ceramic crowns as well as measure the veneer and core thickness. Scanning electron microscopy (SEM) was used to examine the fracture sites of clinically failed prostheses. Micro X-ray CT analysis revealed the distribution patterns of pores within the all-ceramic prostheses, and SEM fractographic analysis indicated a strong relationship between the existence of pores and crack propagation. Therefore, micro X-ray CT is a useful tool for nondestructive inspection of the internal morphology of all-ceramic prostheses to identify the critical defects before seating.
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