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1.
Jpn Dent Sci Rev ; 60: 40-43, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38204963

RESUMO

The publication status of dental journals in Japan was examined, with a focus on metrics such as Journal Impact Factor (JIF), Eigenfactor, Article Influence Score, and percentage of open access. A total of 18 journals published by Japanese dental organizations were identified in the Journal Citation Reports (JCR), with JIF values ranging from 0.4 to 6.6. The highest JIF was observed in The Japanese Dental Science Review. Additionally, 16 journals were not listed on the JCR. The authors explored the implications of these findings on the visibility and impact of Japanese dental research, and discussed the potential benefits of embracing open-access publications for greater global dissemination. This study highlighted the opportunities for journals to enhance their international recognition by meeting the criteria for JIF inclusion and embracing open-access publications. By adopting effective publication strategies, the dental community in Japan will be able to contribute to the advancement of dentistry globally, ensuring broader accessibility and recognition of its research contributions.

2.
Dent Mater J ; 42(4): 478-484, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37121735

RESUMO

This study investigated the effect of 10-methacryloyloxydecyl dihydrogen phosphate (MDP) in methyl methacrylate (MMA) monomer on the adhesion of tri-n-butylborane (TBB)-initiated resins (MDP/MMA-TBB resins) to human enamel. Enamel surface conditions were either polished only or phosphatized surfaces. The 1.0, 1.7, and 2.0 mol% MDP/MMA-TBB resins, 4-methacryloxyethyl trimellitate anhydride (4-META)/MMA-TBB resin and MMA-TBB resin were prepared as luting materials. The shear bond strength was determined before and after thermocycles, and the results were compared using non-parametric statistical analyses (each, n=15). The MDP/MMA-TBB resins showed significantly better bond durability to enamel than other resins with or without etching. The 1.7 and 2.0 mol% MDP/MMA-TBB resins were suggested to be the optimum MDP concentrations from pre- and post-thermocycling results for the non-etched specimens. The TBB initiator resin including MDP was shown to be effective in bonding to human enamel, and this effect was enhanced in combination with phosphate treatment.


Assuntos
Colagem Dentária , Metilmetacrilatos , Humanos , Metilmetacrilatos/química , Metilmetacrilato/química , Compostos de Boro/química , Metacrilatos/química , Esmalte Dentário , Colagem Dentária/métodos , Teste de Materiais , Cimentos de Resina/química
3.
Dent Mater J ; 42(3): 418-425, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36935125

RESUMO

This study evaluated the effect of luting system with acidic primers on the durability of bonds with Ti-15Mo-5Zr-3Al titanium alloy (Ti-15Mo-5Zr-3Al) and its component metals. Adherend metals were Ti-15Mo-5Zr-3Al, Ti, Mo, Zr, and Al. Four primers were evaluated as adhesion promoters: Alloy Primer (ALP), Estenia Opaque Primer (EOP), M. L. Primer (MLP), and Super Bond liquid (SBL). An acrylic resin was used as the luting material. Pre- and post-thermocycling shear bond strength was determined to evaluate the bonding durability, and the results were compared using non-parametric statistical analyses (n=11/group). The post-thermocycling bond strength in MPa (median) associated with ALP, EOP, MLP, and SBL were 18.8, 19.8, 4.1, and 0.8, respectively, for Ti-15Mo-5Zr-3Al. The results showed that two primers containing 10-methacryloyloxydecyl dihydrogen phosphate (MDP) were effective for the durability of bonding of Ti-15Mo-5Zr-3Al to the resin. MDP enhanced the bonding durability of the resin bonded to either Ti, Zr, or Al.


Assuntos
Colagem Dentária , Titânio , Titânio/química , Colagem Dentária/métodos , Teste de Materiais , Metacrilatos/química , Resistência ao Cisalhamento , Cimentos de Resina/química
4.
Front Plant Sci ; 14: 1071648, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938036

RESUMO

Bitter gourd is an important vegetable crop grown throughout the tropics mainly because of its high nutritional value. Sex expression and identification of gynoecious trait in cucurbitaceous vegetable crops has facilitated the hybrid breeding programme in a great way to improve productivity. In bitter gourd, gynoecious sex expression is poorly reported and detailed molecular pathways involve yet to be studied. The present experiment was conducted to study the inheritance, identify the genomic regions associated with gynoecious sex expression and to reveal possible candidate genes through QTL-seq. Segregation for the gynoecious and monoecious sex forms in the F2 progenies indicated single recessive gene controlling gynoecious sex expression in the genotype, PVGy-201. Gynoecious parent, PVGy-201, Monoecious parent, Pusa Do Mausami (PDM), and two contrasting bulks were constituted for deep-sequencing. A total of 10.56, 23.11, 15.07, and 19.38 Gb of clean reads from PVGy-201, PDM, gynoecious bulk and monoecious bulks were generated. Based on the ΔSNP index, 1.31 Mb regions on the chromosome 1 was identified to be associated with gynoecious sex expression in bitter gourd. In the QTL region 293,467 PVGy-201 unique variants, including SNPs and indels, were identified. In the identified QTL region, a total of 1019 homozygous variants were identified between PVGy1 and PDM genomes and 71 among them were non-synonymous variants (SNPS and INDELs), out of which 11 variants (7 INDELs, 4 SNPs) were classified as high impact variants with frame shift/stop gain effect. In total twelve genes associated with male and female gametophyte development were identified in the QTL-region. Ethylene-responsive transcription factor 12, Auxin response factor 6, Copper-transporting ATPase RAN1, CBL-interacting serine/threonine-protein kinase 23, ABC transporter C family member 2, DEAD-box ATP-dependent RNA helicase 1 isoform X2, Polygalacturonase QRT3-like isoform X2, Protein CHROMATIN REMODELING 4 were identified with possible role in gynoecious sex expression. Promoter region variation in 8 among the 12 genes indicated their role in determining gynoecious sex expression in bitter gourd genotype, DBGy-1. The findings in the study provides insight about sex expression in bitter gourd and will facilitate fine mapping and more precise identification of candidate genes through their functional validation.

5.
J Prosthodont Res ; 67(2): 189-195, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35644569

RESUMO

PURPOSE: To investigate the effect of prosthodontic treatment on the ingestible food profile in adult Japanese outpatients, and to identify the related risk factors that can deteriorate the profile. METHODS: The participants were 277 outpatients who visited university-based specialty clinics in Japan for prosthodontic treatment. The demographic data, number of present teeth assessed via intraoral examination, and oral health-related quality of life assessed by the total Oral Health Impact Profile (OHIP-J54) scores of all participants were recorded before treatment. Ingestible food profile score (IFS) was recorded using a validated food intake questionnaire. Eligible participants who answered the questionnaire before and after treatment were categorized into five groups based on the prosthodontic treatments they received (i.e., crowns, bridges, removable partial dentures, removable complete dentures, and removable complete and partial dentures). RESULTS: Multivariate analysis of covariance revealed a statistically significant main effect of prosthodontic intervention (time course: before and after treatment) on mean IFS (P=0.035, F=4.526), even after adjusting for covariates (age, number of present teeth, and treatment modality). Multiple linear regression analysis revealed that the low number of present teeth (r=0.427, P<0.001) and a high OHIP-J54 total score (r=-0.519, P<0.001) of the patients at the baseline were significantly associated with their baseline IFSs, even after adjusting for confounding variables. CONCLUSIONS: The findings of this multicenter follow-up study indicate the importance of prosthodontic rehabilitation in improving patients' ingestible food profiles.


Assuntos
Prótese Parcial Removível , Qualidade de Vida , Adulto , Humanos , População do Leste Asiático , Seguimentos , Saúde Bucal , Pacientes Ambulatoriais , Prostodontia , Alimentos , Dieta
6.
J Prosthodont Res ; 67(1): 150-156, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35569998

RESUMO

PURPOSE: To clarify the effect of a multi-purpose primer combining several functional monomers on two prosthodontic materials (cast titanium and a gold alloy) after airborne-particle abrasion. METHODS: Disk-shaped adherends were prepared from cast titanium (CP Titanium JIS2) and a gold alloy (Casting Gold M.C. Type IV). A silane-containing two-liquid primer (M&C primer (MC)) and two silane-free single-liquid primers (Alloy Primer (AP) and V-Primer (VP)) were used as surface-treatment agents. The shear bond strengths were determined before and after thermocycling to evaluate the adhesive durability, and the results were compared using a non-parametric statistical analysis. The effect of airborne-particle abrasion with alumina on the titanium surface was analyzed by X-ray photoelectron spectroscopy (XPS). RESULTS: There was no significant difference in bond strength between the MC and AP before and after thermocycling, whereas VP showed significantly lower values. XPS revealed that the titanium acquired hydrophilic properties after the airborne-particle abrasion. CONCLUSIONS: The novelty of this study is that it shows that the presence/absence of the silane had no effect on the bonding of cast titanium with an acrylic resin. The study also showed that the multi-purpose primer can be used without any problems with both cast titanium and gold alloy, in combination with airborne-particle abrasion with alumina.


Assuntos
Resinas Acrílicas , Colagem Dentária , Resinas Acrílicas/química , Ligas de Ouro/química , Titânio/química , Metacrilatos/química , Resistência ao Cisalhamento , Óxido de Alumínio/química , Teste de Materiais , Cimentos de Resina/química , Propriedades de Superfície
7.
Front Plant Sci ; 14: 1258042, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38333042

RESUMO

Introduction: Momordica balsamina is the closest wild species that can be crossed with an important fruit vegetable crop, Momordica charantia, has immense medicinal value, and placed under II subclass of primary gene pool of bitter gourd. M. balsamina is tolerant to major biotic and abiotic stresses. Genome characterization of Momordica balsamina as a wild relative of bitter gourd will contribute to the knowledge of the gene pool available for improvement in bitter gourd. There is potential to transfer gene/s related to biotic resistance and medicinal importance from M. balsamina to M. charantia to produce high-quality, better yielding and stress tolerant bitter gourd genotypes. Methods: The present study provides the first and high-quality chromosome-level genome assembly of M. balsamina with size 384.90 Mb and N50 30.96 Mb using sequence data from 10x Genomics, Nanopore, and Hi-C platforms. Results: A total of 6,32,098 transposons elements; 2,15,379 simple sequence repeats; 5,67,483 transcription factor binding sites; 3,376 noncoding RNA genes; and 41,652 protein-coding genes were identified, and 4,347 disease resistance, 67 heat stress-related, 05 carotenoid-related, 15 salt stress-related, 229 cucurbitacin-related, 19 terpenes-related, 37 antioxidant activity, and 06 sex determination-related genes were characterized. Conclusion: Genome sequencing of M. balsamina will facilitate interspecific introgression of desirable traits. This information is cataloged in the form of webgenomic resource available at http://webtom.cabgrid.res.in/mbger/. Our finding of comparative genome analysis will be useful to get insights into the patterns and processes associated with genome evolution and to uncover functional regions of cucurbit genomes.

8.
Geriatr Gerontol Int ; 22(12): 1032-1039, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36408675

RESUMO

AIM: To examine the relationship between the number of present and functional teeth at baseline and future incidence of loss of independence. METHODS: Participants were community-dwelling older individuals who participated in a comprehensive geriatric health examination conducted in Kusatsu town, Japan, between 2009 and 2015. The primary endpoint was the incidence of loss of independence among participants, defined as the first certification of long-term care insurance in Japan. The numbers of present and functional teeth at baseline were determined via an oral examination. Demographics, clinical variables (e.g., history of chronic diseases and psychosocial factors), blood nutritional markers, physical functions, and perceived masticatory function were assessed. RESULTS: This study included 1121 individuals, and 205 individuals suffered from loss of independence during the follow-up period. Kaplan-Meier estimates of loss of independence for participants with smaller numbers of present and functional teeth were significantly greater than for those with larger numbers of teeth. Cox proportional hazard analyses indicated that a smaller number of present teeth was not a significant risk factor after adjusting for demographic characteristics. However, the number of functional teeth was a significant risk factor after the adjustment (hazard ratio: 1.975 [1.168-3.340]). Additionally, higher hazard ratios were observed in other adjusted models, but they were not statistically significant. CONCLUSIONS: The number of functional teeth may be more closely related to the future incidence of loss of independence than the number of present teeth. This novel finding suggests that prosthodontic rehabilitation for tooth loss possibly prevents the future incidence of this life-event. Geriatr Gerontol Int 2022; 22: 1032-1039.


Assuntos
Perda de Dente , Humanos , Idoso , Japão/epidemiologia , Perda de Dente/epidemiologia , Certificação , Vida Independente , Seguro de Assistência de Longo Prazo
9.
Dent Mater J ; 41(2): 279-285, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980767

RESUMO

This study assessed the effect of a primer containing 10-methacryloyloxydecyl-(2-thiohydantoin-4-yl)propionate (MDTHP) on the bonding of noble metal alloys to an acrylic resin. Three noble metal alloys were selected as adherends, and V-Primer containing 6-(4-vinylbenzyl-n-propyl)amino-1,3,5-triazine-2,4-dithione was used as a comparative control. The disk specimens of each noble metal alloy were wet-ground and divided into three conditions: specimens primed with MDTHP primer or V-Primer, and specimens without priming. An acrylic resin was bonded to each specimen, and the specimens were performed the shear bond test. The MDTHP primer showed higher shear bond strength than the V-Primer for all specimens. X-ray photoelectron spectroscopic analysis showed that MDTHP was adsorbed on the Au-Pt-Pd alloy surface even after acetone cleaning. MDTHP binds not only with Cu but also with Au and Ag, promoting the bond strength of noble metal alloys. The effectiveness of MDTHP on dental noble metal alloys was suggested.


Assuntos
Colagem Dentária , Metacrilatos , Ligas , Ligas Dentárias/química , Ligas de Ouro/química , Teste de Materiais , Metacrilatos/química , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície , Tioidantoínas
10.
Dent Mater J ; 41(1): 117-125, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34483203

RESUMO

The effects of mechanical retentive devices and various surface treatments on the shear bond strength between a veneering composite resin and zirconia was investigated. Zirconia disks were classified into three surface-treatment groups: airborne-particle abrasion, overglazing, and overglazing with white alumina particles of three different grain sizes (50, 70, and 105 µm) attached onto zirconia disks (ZR-50, ZR-70, and ZR-105, respectively). They were further divided into four groups (n=44): unprimed, Clearfil Porcelain Bond Activator (CA), Clearfil Photo Bond (CB), and CA+CB. An indirect composite resin was bonded to zirconia specimens. Shear bond strengths were measured. For the ZR-70 and ZR-105 groups, the CB and CA+CB specimens exhibited higher bond strengths than the other two specimens after thermocycling. The ZR-70 and ZR-105 groups achieved micromechanical interlocking, and priming with a phosphate monomer (MDP) yielded stable bond strengths between the composite resin and zirconia with alumina particles attached as retentive devices.


Assuntos
Resinas Compostas , Colagem Dentária , Cerâmica , Porcelana Dentária , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
11.
Dent Mater J ; 41(1): 60-67, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471042

RESUMO

This study assessed the gloss and surface roughness of computer-aided design/computer-aided manufacturing (CAD/CAM) resin composites corroded with acidulated phosphate fluoride (APF) application. One ceramic block, ten CAD/CAM resin composites for premolars, and four CAD/CAM resin composites for molars were assessed. The surface topography of the materials before and after APF application was observed using an electron microscope. The results were analyzed by Wilcoxon signed-rank test and Dunnett's many to one test (p<0.05). Gloss after APF application was significantly lower for all CAD/CAM resin composites except Artesano. Ra after APF application was significantly higher for all CAD/CAM resin composites except Artesano, Dentcraft HR Block, and Estelite P Block, and Sa was significantly higher for all CAD/CAM resin composites. Irregular surface topography was observed after APF application and the surface features differed among the materials. Therefore, APF application may be detrimental to the surface properties of CAD/CAM resin composites.


Assuntos
Fluoreto de Fosfato Acidulado , Resinas Compostas , Cerâmica , Desenho Assistido por Computador , Coroas , Teste de Materiais , Propriedades de Superfície
12.
J Prosthodont Res ; 66(2): 333-338, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-34544942

RESUMO

PURPOSE: This study evaluated the influence of firing procedures and layering thickness of porcelain on internal adaptation of maxillary anterior cantilever zirconia resin-bonded fixed dental prostheses (RBFDPs). METHODS: The maxillary right central incisor on a model was prepared for a single-retainer zirconia RBFDP. A total of 36 frameworks of cantilever zirconia RBFDPs were classified into three groups (CB0.5, CB1.0, and CB2.0 groups) based on the thickness of the cut-back on the facial surface (0.5 mm, 1.0 mm, and 2.0 mm, respectively). Feldspathic porcelain was layered onto the facial surface of the zirconia RBFDP frameworks. Internal space widths between the abutment tooth and the framework were measured before and after porcelain firing by a replica technique. The internal space values before and after porcelain firings were compared using the paired t-test within the same group (α = 0.05). Differences in internal space values (distortion) between before and after porcelain firing were compared using one-way analysis of variance and Tukey multiple comparison tests. RESULTS: For all framework designs, internal space values after porcelain firing were significantly higher than those before firing. Among all groups, the CB0.5 group showed the lowest internal distortion values for the whole measured area. The CB2.0 group showed higher distortion values than the CB1.0 group. CONCLUSION: Porcelain firing procedures negatively impacted the internal space in cantilever zirconia RBFDPs. In addition, the increased volume of layering porcelain had a negative effect on the internal distortion of maxillary anterior cantilever zirconia RBFDPs.


Assuntos
Colagem Dentária , Prótese Dentária , Porcelana Dentária , Zircônio
13.
Mol Genet Genomics ; 296(6): 1323-1335, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34609588

RESUMO

Sex form is one of the most important characteristics in papaya cultivation in which hermaphrodite is the preferable form. Self-pollination of H*-TSS No.7, an inbred line derived from a rare X chromosome mutant SR*, produced all-hermaphrodite progeny. The recessive lethal allele controlling the all-hermaphrodite phenomenon was proposed to be the recessive Germination suppressor (gs) locus. This study employed next-generation sequencing technology and genome comparison to identify the candidate Gs gene. One specific gene, monodehydroascorbate reductase 4 (MDAR4) harboring a unique polymorphic 3 bp deletion in H*-TSS No.7 was identified. The function of MDAR4 is known to be involved in the hydrogen peroxide (H2O2) scavenging pathway and is associated with seed germination. Furthermore, MDAR4 showed higher expression in the imbibed seeds than that in the dry seeds indicating its potential role in the seed germination. Perhaps this is the very first report providing the evidences that MDAR4 is the candidate of Gs locus in H*-TSS No.7. In addition, Gs allele-specific markers were developed which would be facilitated for breeding all-hermaphrodite lines.


Assuntos
Carica/genética , Cromossomos de Plantas/genética , Organismos Hermafroditas/genética , NADH NADPH Oxirredutases/genética , Genoma de Planta/genética , Germinação/genética , Peróxido de Hidrogênio/metabolismo , Polinização/genética , Polinização/fisiologia , Sementes/crescimento & desenvolvimento , Deleção de Sequência/genética
14.
Materials (Basel) ; 14(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918316

RESUMO

This study was conducted to clarify the influence of the copper surface oxidation and reduction on the shear-bond strength with functional monomers. Unheated copper specimens (UH; n = 88) were wet-ground. Three-quarters of the UH were then heated (HT). Two-thirds of the HT was then immersed in a hydrochloric acid solution (AC). Half of the AC was then reheated (RH). Each group was further divided into two groups (n = 11), which were primed by either 6-methacryloyloxyhexyl 2-thiouracil-5-carboxylate (MTU-6) or 10-methacryloyloxydecyl dihydrogen phosphate (MDP). The shear-bond strength tests were used for bonding with an acrylic resin. The surface roughness values and chemical states of the four groups were analyzed using a confocal scanning laser microscope and X-ray photoelectron spectroscopy (XPS). The shear-bond strengths of HT and RH were the lowest in the MTU-6-primed groups. The result of AC was significantly lower than others in the MDP-primed groups. The XPS results showed that the surfaces of UH and AC consisted of Cu2O and Cu. The surface changed to CuO upon heating. The presence or absence of copper-oxide films showed the opposite trends in the effectiveness of MTU-6 and MDP to improve bond strength. The results could elucidate the effects of functional monomers on copper-oxide films.

15.
J Prosthodont Res ; 65(3): 267-272, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-33612664

RESUMO

Purpose In this review, we evaluate the survival rate of resin-bonded fixed partial dentures (RBFPDs) made of metal alloys.Methods An electronic search of English peer-reviewed dental literature on PubMed was conducted to identify all publications reporting on RBFPDs made of metal alloys until March 2019. The searched keywords were: bridge OR fixed partial denture OR fixed prosthesis OR fixed prostheses AND resin bonded AND metal OR alloy AND survival OR longevity (RBFPD was not included). Furthermore, the "Related Articles" feature of PubMed was used to identify further references of interest during the primary search. A definitive list of articles was screened to extract qualitative data after the application of the inclusion and exclusion criteria, and the results were analyzed.Results Overall, 977 publications were found through an electronic and manual search, out of which 130 articles were selected after screening based on title and abstract. A total of 52 publications passed the second review phase after assessment for eligibility, from which 24 studies were excluded after full-text screening. Finally, a total of 28 studies were selected.Conclusions The survival rate of RBFPDs differed greatly depending on the type of metal alloy, adhesion system, and observation period assessed, e.g. the 10-year survival rate ranged from 18% to 88%. The wide range of survival rates of the RBFPDs reported indicates that though RBFPD is a reliable prosthesis, it is prone to failure if some processes are not completed.


Assuntos
Prótese Adesiva , Ligas , Falha de Restauração Dentária , Planejamento de Dentadura , Retenção de Dentadura , Prótese Parcial Fixa
16.
Dent Mater J ; 40(3): 664-673, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33456028

RESUMO

This study investigated the influence of roughening procedures and application of primers on shear bond strengths of CAD/CAM composite resin material or ceramic material to zirconia frameworks. A CAD/CAM composite resin block (Katana Avencia Block; AVE) and lithium disilicate glass-ceramic block (IPS e.max CAD; IEC) were used as veneer materials. The veneers were divided into three surface treatment groups; HF, hydrofluoric acid etching; AB, airborne-particle abrasion; and CON, no surface treatment. Each veneer was primed with four agents: Clearfil Porcelain Bond Activator (ACT), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Porcelain Bond Activator (CPB+ACT), and no priming (UP). The zirconia frameworks and AVE or IEC veneers were resin-bonded. In the AVE specimen, AB treatment showed significantly higher shear bond strength than the other treatments at 0 and 20,000 thermocycles, except for UP and CPB+ACT groups at 20,000 thermocycles. Airborne-particle abrasion is necessary for resin bonding to Avencia blocks.


Assuntos
Colagem Dentária , Cerâmica , Porcelana Dentária , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
17.
Eur J Oral Sci ; 129(2): e12762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33501688

RESUMO

This study determined the shear bond strength (SBS) between an indirect gingival composite resin and glazed gingival porcelain after various surface treatments. A total of 176 porcelain disks with natural glazing were used and assigned to one of four groups: no surface treatment, airborne-particle abrasion, hydrofluoric acid etching, or a combination of airborne-particle abrasion followed by hydrofluoric acid etching. Each group was divided into two subgroups: one subgroup was unprimed, and the other was silanized. An indirect composite resin was then bonded to the porcelain disks. Half of the specimens in each group (n = 11) were exposed to 5000 thermocycles. SBSs were measured, and data were analyzed with the Kruskal-Wallis and Steel-Dwass tests. Among silanized specimens, those treated with the combination of airborne-particle abrasion and hydrofluoric acid etching exhibited the highest bond strengths both before and after thermocycling. However, the SBS values of the silanized and unprimed hydrofluoric acid etched specimens did not differ significantly. Airborne-particle abrasion followed by hydrofluoric acid etching with silane application yielded stronger, more durable bonds between the indirect gingival composite resin and glazed gingival porcelain.


Assuntos
Colagem Dentária , Implantes Dentários , Condicionamento Ácido do Dente , Resinas Compostas , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
18.
Dent Mater ; 37(3): e176-e181, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33341246

RESUMO

OBJECTIVE: The purpose of this study was to assess the effects of an experimental primer containing acetone solution and a sulfur-containing functional monomer, 10-methacryloyloxydecyl-(2-thiohydantoin-4-yl)propionate (MDTHP), on the bonds between noble metals and acrylic resin. METHODS: The experimental primer used as the control for comparison consisted of 6-(4-vinylbenzyl-n-propyl)amino-1,3,5-triazine-2,4-dithione (VBATDT) in acetone. These primers were prepared as equimolar functional monomers (0.1 mol%). A self-polymerizing acrylic resin initiated with tri-n-butylborane (TBB) was used as the luting agent. Four elemental metal disks (silver, copper, palladium, and gold) were used as adherend specimens. All the disks were wet-ground with silicon carbide paper (#1500). Bonding reactions were performed on 12 combinations of the four metals, and the disks were either primed with MDTHP or VBATDT or were unprimed (control). Shear bond strengths were determined pre- and post-thermocycling (5-55 °C, dwell time 60 s, 20,000 cycles). The results were statistically analyzed via a non-parametric test (α = 0.05). RESULTS: The post-thermocycling shear bond strengths of the MDTHP primer were as follows (median, n = 11): 13.2 MPa on silver, 25.9 MPa on copper, 4.1 MPa on palladium, and 11.3 MPa on gold. The MDTHP primer showed higher post-thermocycling shear bond strength on all the four metals. Additionally, on silver and copper, the MDTHP bond strengths were higher than on the other metals. SIGNIFICANCE: Within the limitation of current of experimental setting, the MDTHP compound may be applicable as a functional monomer for bonding noble metal alloys.


Assuntos
Colagem Dentária , Cimentos de Resina , Compostos de Boro , Cimentos Dentários , Ligas de Ouro , Teste de Materiais , Metacrilatos , Resistência ao Cisalhamento , Tioidantoínas
19.
J Oral Sci ; 63(1): 119-120, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33281146

RESUMO

Cast titanium restoration for molars has high biocompatibility and is covered by the Japanese national health insurance. Titanium casting requires specific investment material and casting apparatus. A cast restoration for the mandibular left second molar was fabricated using titanium in this study. A wax pattern fabricated on a definitive cast was invested in calcium aluminate-bonded magnesia investment material. Titanium was cast using an argon gas pressure one-chamber casting apparatus. No defects were observed on the surface and the hole was clearly reproduced. A smooth surface on the restoration was obtained by polishing at low speed. Reproductivity and polishing properties of the titanium restoration fabricated in this study were comparable to those of conventional dental metal restorations.


Assuntos
Revestimento para Fundição Odontológica , Titânio , Compostos de Alumínio , Compostos de Cálcio , Técnica de Fundição Odontológica , Óxido de Magnésio , Teste de Materiais , Propriedades de Superfície
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