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1.
Sci Rep ; 13(1): 20848, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012343

RESUMO

Circulating tumor DNA (ctDNA) provides molecular information on tumor heterogeneity. The prognostic usefulness of ctDNA after first-line epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are limited. Therefore, the present study evaluated ctDNA during osimertinib administration as a second-line or more setting to identify the relationship between EGFR mutation levels and outcomes in patients with advanced non-small cell lung cancer (NSCLC). Forty patients with EGFR T790M-positive NSCLC receiving osimertinib after prior EGFR-TKI treatment were registered. Plasma samples were collected at osimertinib pretreatment, after 1 month of treatment, and at the time of progressive disease (PD). ctDNA analysis was performed by digital polymerase chain reaction. The detection rate of copy numbers of exon 19 deletion, L858R, and T790M in plasma samples was significantly lower 1 month after osimertinib than at pretreatment, and significantly higher at PD than at 1 month, whereas that of C797S was significantly higher at PD than at 1 month. No statistically significant difference was observed in the copy numbers of exon 19 deletion, L858R, T790M, and C797S between complete response or partial response and stable disease or PD. The detection of T790M at PD after osimertinib initiation was a significant independent prognostic factor for predicting shorter prognosis, and the presence of major EGFR mutations at pretreatment and PD was closely linked to worse survival after osimertinib initiation. Molecular testing based on ctDNA is helpful for predicting outcomes of osimertinib treatment in T790M-positive NSCLC after previous EGFR-TKI treatment.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , DNA Tumoral Circulante/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores ErbB , Antineoplásicos/uso terapêutico , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Compostos de Anilina/uso terapêutico
2.
Rheumatol Int ; 41(9): 1641-1650, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34056682

RESUMO

Anti-neutrophil cytoplasmic antibodies-associated vasculitis (AAV) occurs in elderly people, and patients with anti-myeloperoxidase autoantibodies (MPO-ANCA)-positive AAV are often complicated with interstitial lung disease (ILD). This study aimed to evaluate the age-related clinical features of elderly patients with MPO-ANCA-positive AAV-ILD. This study retrospectively investigated 63 patients with MPO-ANCA-positive AAV-ILD, all of whom were 65 years or older at diagnosis. Clinical characteristics, causes of death and survival rates among three groups stratified by age (65-74 years, n = 29; 75-79 years, n = 18; over 80 years, n = 16) were compared. This study also examined the association with severe infections in these patients. Among the three age groups, there were significant differences in sex (P = 0.032), serum Krebs von den Lungen-6 (P < 0.01), and total ground-glass opacity score (P = 0.011). The causes of death were mainly severe infections and complications of ILD. Kaplan-Meier curve analysis showed a significantly lower 5-year survival rate in the oldest group (P < 0.01). Regarding severe infections in these patients, the 5-year cumulative incidence of severe infections was higher in the patients receiving steroid pulse therapy (P = 0.034). The clinical characteristics of MPO-ANCA-positive AAV-ILD differ with age in elderly patients, with age being an important poor prognostic factor in these patients. The administration of steroid pulse therapy is a significant risk factor of severe infection in MPO-ANCA-positive elderly patients with AAV-ILD.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Doenças Pulmonares Intersticiais/imunologia , Idoso , Idoso de 80 Anos ou mais , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/mortalidade , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/fisiopatologia , Autoanticorpos/sangue , Feminino , Humanos , Estimativa de Kaplan-Meier , Doenças Pulmonares Intersticiais/mortalidade , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Estudos Retrospectivos
3.
Respir Med Case Rep ; 32: 101361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33643837

RESUMO

A 67-year-old man with stage IV B lung adenocarcinoma was treated with pembrolizumab. The patient was admitted to the hospital because of influenza on the day of the second cycle of pembrolizumab treatment. He was diagnosed with pneumonia and was treated with antiviral drugs and steroids. However, the patient eventually died. In this case, treatment with immune checkpoint inhibitors might have affected the immune response caused by influenza virus infection, that might have caused lung injury, which is an immune-related adverse event (irAE). Hence, it is important that, caution should be taken to prevent transmission of viral infection, and Therefore, it is important to prevent viral infections, but caution should also be paid to the possibility that infections may cause irAEs in patients with lung cancer.

4.
Mod Rheumatol ; 31(1): 177-185, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32149542

RESUMO

OBJECTIVES: Anti-melanoma differentiation-associated gene 5 (MDA5) autoantibody-positive and age at onset ≥60 years are poor prognosis factors in polymyositis (PM) and dermatomyositis (DM) associated with interstitial lung disease (ILD) among Japanese patients. However, the influence of age on the clinical features of anti-MDA5 autoantibody-positive patients with DM remains unclear. METHODS: We retrospectively examined 40 patients with DM and anti-MDA5 autoantibodies according to age. We compared patients aged <60 and ≥60 years with respect to clinical features including laboratory test findings, high-resolution lung computed tomography data, treatment content, and complications such as infections and prognosis. We also examined clinical features between surviving and deceased patients in the older patient group. RESULTS: Of 40 enrolled patients, 13 were classified as old and 27 as young. Older patients had significantly fewer clinical symptoms including arthralgia/arthritis (p < .01), skin ulceration (p = .02), and higher mortality than younger patients (p = .02) complicated with rapidly progressive ILD (RP-ILD), combination immunosuppressive therapy, and strictly controlled infections. CONCLUSION: Clinical features and mortality of anti-MDA5 autoantibody-positive DM patients were influenced by age. Patients aged ≥60 years had a worse prognosis, and combination immunosuppressive therapy was often ineffective for RP-ILD in older patients.


Assuntos
Autoanticorpos/imunologia , Dermatomiosite/patologia , Helicase IFIH1 Induzida por Interferon/imunologia , Adulto , Fatores Etários , Idoso , Dermatomiosite/tratamento farmacológico , Dermatomiosite/epidemiologia , Dermatomiosite/imunologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mortalidade
5.
Sci Rep ; 10(1): 6199, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32277100

RESUMO

Novel amorphous iron hydrides (AIHs) are synthesized for the first time under ambient conditions by employing novel "quiescent reaction", without stirring for mixing solutions, during a conventional aqueous reduction-precipitation process. The kind and morphology of AIHs are dependent on the processing condition, where two types are found, with one form consisting of a tangle of uniform nanowires and the other being granular in nature. Both AIHs undergo transformation to crystalline α-Fe by heat treatment at 600 °C. The nanowire AIH exhibits the hydrogen content of 0.10 wt%, while the granular AIH of 0.22 wt%. Their magnetic and thermal properties are accordingly different, and the non-diffusive hydrogen contributes to stability of AIHs. It is strongly suggested that, by use of quiescent reaction, iron-hydrogen clusters are formed and preserved at an early stage of precipitation reaction, and subsequently aggregated into novel AIHs, preventing α-Fe crystallization. Hence, the AIHs would be categorized as metastable hydrides stabilized with iron-hydrogen clusters. In addition, newly discovered quiescent reaction in aqueous solution, from which unprecedented AIHs are derived, sheds new light on fundamental and essential aqueous reaction.

6.
Clin Rheumatol ; 38(12): 3443-3450, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31420814

RESUMO

BACKGROUND: Dermatomyositis (DM) with autoantibody against melanoma differentiation-associated gene-5 (MDA5) is characterized by elevated risk of rapidly progressive interstitial lung disease (RP-ILD) with a potentially fatal course. Pneumomediastinum (PNM) is a common pulmonary manifestation which accompanies ILD. However, the clinical features of the patients with anti-MDA5 antibody-positive DM who develop PNM remain unclear. METHODS: We retrospectively examined 31 patients with DM having anti-MDA5 antibody and compared the clinical features between patients with PNM (PMN(+)) (n = 11) and those without (PNM(-) (n = 20). In addition, we evaluated the treatment-related prognoses in PNM(+) group. RESULTS: CT score (total ground-glass opacity (GGO) score, P = 0.02; total fibrosis score, P = 0.02) before treatment, and mortality (P = 0.04) were significantly higher in PNM(+) group. The cumulative survival rate as assessed by Kaplan-Meier method was significantly lower for the PNM(+) group (P = 0.02). Among 11 PMN(+) patients, 9 patients (9/11, 81.8%) underwent intensive immunosuppression therapy for RP-ILD, and 5 patients (5/11, 45.5%) did not respond to it and died from the respiratory failure. At the time of diagnosis of PNM, nonsurvivors had worse liver function (ALT, P = 0.03; LDH, P = 0.01), worse respiratory status (A-aDO2, P = 0.01), and worse CT score (total GGO score, P < 0.01). CONCLUSIONS: A subgroup of patients with DM having anti-MDA5 antibody complicated by PNM as well as RP-ILD did respond to intensive immunosuppression therapy. Initial aggressive immunosuppressive therapy should be considered for these patients.Key Points• This study clearly demonstrate the presence of PNM was associated with elevated risk of death due to respiratory failure from RP-ILD among patients with DM having circulating anti-MDA5-antibody.•This study demonstrate evaluation of CT image may be helpful to find patients with better response to the intense immunosuppression therapy for the patients with DM having circulating anti-MDA5-antibody and PNM.


Assuntos
Dermatomiosite/complicações , Helicase IFIH1 Induzida por Interferon/imunologia , Enfisema Mediastínico/etiologia , Adulto , Idoso , Dermatomiosite/diagnóstico , Dermatomiosite/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
7.
Respir Med ; 140: 1-5, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29957268

RESUMO

BACKGROUND: Anti-melanoma differentiation-associated gene 5 (MDA5) autoantibodies have been identified as myositis-specific autoantibodies that are often associated with clinically amyopathic dermatomyositis (CADM) and a poor prognosis due to rapidly progressive interstitial lung disease (RP-ILD) in East Asian patients. Besides anti-MDA5 autoantibodies, patients with CADM may have myositis-associated autoantibodies (MAAs), which characterize other connective tissue diseases such as rheumatoid arthritis and Sjögren's syndrome. However, the clinical significance of the coexistence of anti-MDA5 autoantibodies and MAAs in patients with CADM remains unclear. METHODS: We retrospectively analyzed 24 patients with CADM who had anti-MDA5 autoantibodies. Their clinical phenotypes including laboratory test results, high-resolution lung computed tomography data, response to therapy, and prognosis were compared between those who were positive and negative for MAAs, such as antinuclear antibody (ANA), anti-cyclic citrullinated peptide (CCP), anti-SSA, and anti-SSB antibodies. RESULTS: Among 24 patients, 9 (37.5%) additionally had at least one of the MAAs examined in this study: 1 patient was positive for ANA, 5 for anti-CCP, 5 for either anti-SSA or anti-SSB, 1 for anti-cardiolipin, and 1 for anti-Scl-70. Although all anti-MDA5-positive patients with CADM had ILD, the MAA-positive patients showed a lower risk of developing RP-ILD (p = 0.03), a more favorable response to combination therapy of corticosteroids and immunosuppressive agents, and a lower mortality rate than patients with no MAAs (p = 0.03). CONCLUSIONS: Our data suggest that anti-MDA5-positive patients with CADM who also have MAAs have a better prognosis than those without MAAs; thus, anti-MDA5 autoantibodies by themselves may not be strong predictors of worse clinical outcomes in patients with CADM. Coexistent MAAs could be biomarkers for a favorable prognosis in anti-MDA5-positive patients with CADM.


Assuntos
Autoanticorpos/sangue , Dermatomiosite/diagnóstico , Helicase IFIH1 Induzida por Interferon/imunologia , Adulto , Idoso , Biomarcadores/sangue , Dermatomiosite/tratamento farmacológico , Dermatomiosite/imunologia , Progressão da Doença , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Estimativa de Kaplan-Meier , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/imunologia , Masculino , Pessoa de Meia-Idade , Miosite/imunologia , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
8.
Dent Mater J ; 37(1): 78-86, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28883302

RESUMO

This study evaluated the effect of zirconia framework design on fracture load of implant-supported zirconia-based prostheses after thermal cycling and mechanical loading. Three different zirconia framework designs were investigated: uniform-thickness (UNI), anatomic (ANA), and supported anatomic (SUP) designs. Each framework was layered with feldspathic porcelain (ZAC group) or indirect composite material (ZIC group). The specimens then underwent fracture load testing after thermal cycling and cyclic loading. In the ZAC group, mean fracture load was significantly lower for UNI design specimens than for the other framework designs. In the ZIC group, there was no significant difference in mean fracture load between ANA design specimens and either UNI or SUP design specimens. To improve fracture resistance of implant-supported zirconia-based prostheses after artificial aging, uniformly thick layering material and appropriate lingual support with zirconia frameworks should be provided.


Assuntos
Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Zircônio/química , Resinas Compostas/química , Desenho Assistido por Computador , Projeto do Implante Dentário-Pivô , Materiais Dentários/química , Porcelana Dentária/química , Análise do Estresse Dentário , Cimentos de Ionômeros de Vidro/química , Teste de Materiais
9.
Clin Oral Implants Res ; 28(9): 1119-1126, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27412687

RESUMO

OBJECTIVES: The objective of this in vitro study was to investigate fracture loads of screw-retained zirconia-based molar restorations (hybrid abutment crown) fabricated with different restorative materials and designs. MATERIAL AND METHODS: Forty-four screw-retained zirconia-based molar restorations were fabricated on dental implants and divided into four groups (n = 11): porcelain-layered zirconia-based restorations (PLZ), indirect composite-layered zirconia-based restorations (ILZ), metal-ceramic restorations (MC), and monolithic zirconia restorations (MONO). The zirconia-based restorations in the PLZ, ILZ, and MONO groups were adhesively bonded on implant abutments with a dual-polymerized resin material. All restorations were tightened on implant bodies with titanium screws and were tested for fracture resistance. The Kruskal-Wallis test and Steel-Dwass test were used to evaluate differences in fracture loads (α = 0.05). RESULTS: As compared with the other groups, the MONO specimens had a significantly higher mean fracture resistance (7.54 kN); no significant differences were found among the PLZ (1.96 kN), ILZ (1.80 kN), and MC (1.45 kN) groups (P > 0.05). For the PLZ, ILZ, and MC groups, all specimens fractured within the layering materials. In contrast, the fracture mode for the MONO group was complete fracture of the restorations. CONCLUSIONS: All restorations withstood the masticatory forces. Fracture loads were significantly higher for screw-retained implant-supported monolithic zirconia restorations than for screw-retained bilayered restorations. For the screw-retained bilayered zirconia-based restorations, the fracture resistance of ILZ restorations was comparable to that of PLZ restorations and MC restorations.


Assuntos
Parafusos Ósseos , Materiais Dentários , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Dente Molar , Zircônio , Projeto do Implante Dentário-Pivô , Teste de Materiais
10.
Clin Oral Implants Res ; 26(12): 1407-13, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25115334

RESUMO

OBJECTIVES: To evaluate the effects of framework design and layering material on the fracture strength of implant-supported zirconia-based molar crowns. MATERIAL AND METHODS: Sixty-six titanium abutments (GingiHue Post) were tightened onto dental implants (Implant Lab Analog). These abutment-implant complexes were randomly divided into three groups (n = 22) according to the design of the zirconia framework (Katana), namely, uniform-thickness (UNI), anatomic (ANA), and supported anatomic (SUP) designs. The specimens in each design group were further divided into two subgroups (n = 11): zirconia-based all-ceramic restorations (ZAC group) and zirconia-based restorations with an indirect composite material (Estenia C&B) layered onto the zirconia framework (ZIC group). All crowns were cemented on implant abutments, after which the specimens were tested for fracture resistance. The data were analyzed with the Kruskal-Wallis test and the Mann-Whitney U-test with the Bonferroni correction (α = 0.05). RESULTS: The following mean fracture strength values (kN) were obtained in UNI design, ANA design, and SUP design, respectively: Group ZAC, 3.78, 6.01, 6.50 and Group ZIC, 3.15, 5.65, 5.83. In both the ZAC and ZIC groups, fracture strength was significantly lower for the UNI design than the other two framework designs (P = 0.001). Fracture strength did not significantly differ (P > 0.420) between identical framework designs in the ZAC and ZIC groups. CONCLUSIONS: A framework design with standardized layer thickness and adequate support of veneer by zirconia frameworks, as in the ANA and SUP designs, increases fracture resistance in implant-supported zirconia-based restorations under conditions of chewing attrition. Indirect composite material and porcelain perform similarly as layering materials on zirconia frameworks.


Assuntos
Coroas , Projeto do Implante Dentário-Pivô , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Dente Molar , Desenho Assistido por Computador , Análise do Estresse Dentário , Humanos , Técnicas In Vitro , Distribuição Aleatória , Titânio , Zircônio
11.
Dent Mater J ; 33(5): 607-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25273039

RESUMO

This study evaluated fracture load of single-tooth, implant-supported, zirconia-based, porcelain- and indirect composite-layered restorations after artificial aging. Forty-four zirconia-based molar restorations were fabricated on implant abutments and divided into four groups, namely, zirconia-based all-ceramic restorations (ZAC group) and three types of zirconia-based composite-layered restorations (ZIC-P, ZIC-E, and ZIC groups). Before layering an indirect composite material, the zirconia copings in the ZIC-P and ZIC-E groups were primed with Clearfil Photo Bond and Estenia Opaque Primer, respectively. All restorations were cemented on the abutments with glass-ionomer cement and then subjected to thermal cycling and cyclic loading. All specimens survived thermal cycling and cyclic loading. The fracture load of the ZIC-P group (2.72 kN) was not significantly different from that of the ZAC group (3.05 kN). The fracture load of the zirconia-based composite-layered restoration primed with Clearfil Photo Bond (ZIC-P) was comparable to that of the zirconia-based all-ceramic restoration (ZAC) after artificial aging.


Assuntos
Porcelana Dentária , Restauração Dentária Permanente , Fraturas dos Dentes/terapia , Zircônio , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura
12.
Clin Oral Implants Res ; 25(8): 983-91, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23730807

RESUMO

OBJECTIVES: This study evaluated the fracture resistance of single-tooth implant-supported zirconia-based indirect composite-layered molar restorations. MATERIAL AND METHODS: Forty-four titanium abutments (GingiHue Post) were placed on dental implants (Osseotite Implant). Standardized single-tooth cement-retained implant-supported mandibular molar restorations were fabricated for each of four test groups (n = 11) as follows: porcelain-fused-to-metal crowns (PFM), zirconia-based all-ceramic crowns (ZAC), zirconia-based indirect composite-layered crowns primed with Estenia Opaque Primer for zirconia frameworks (ZIC-E), and zirconia-based indirect composite-layered crowns (ZIC). The crowns were luted with a glass-ionomer cement (Ketac Cem Easymix). Fracture resistance (N) was determined by force application of a perpendicular load to the crowns with a universal testing machine. One-way analysis of variance (ANOVA) and the Tukey's HSD test were used to assess differences in fracture resistance values (α = 0.05). RESULTS: Mean fracture resistances (SD) were 3.09 (0.22) kN, 3.11 (0.34) kN, 2.84 (0.21) kN, and 2.50 (0.36) kN for the PFM, ZAC, ZIC-E, and ZIC groups, respectively. Fracture resistance in the ZIC specimens was significantly lower (P < 0.044) than that in the other groups, which did not significantly differ. CONCLUSIONS: The fracture resistance of single-tooth implant-supported zirconia-based indirect composite-layered molar crowns primed with Estenia Opaque Primer for zirconia frameworks (ZIC-E) is comparable to that of porcelain-fused-to-metal (PFM) and zirconia-based all-ceramic (ZAC) restorations. Application of Estenia Opaque Primer to zirconia ceramic framework provides superior fracture resistance in implant-supported zirconia-based indirect composite-layered molar crowns.


Assuntos
Implantes Dentários para Um Único Dente , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Análise do Estresse Dentário , Dente Molar/cirurgia , Dente Suporte , Planejamento de Prótese Dentária , Humanos , Técnicas In Vitro , Titânio , Zircônio
13.
Acta Odontol Scand ; 71(3-4): 457-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23638856

RESUMO

OBJECTIVE: The purpose of the present study was to evaluate the durability of bond strength between an indirect composite material and zirconia ceramics after thermocycling (100 000 cycles) and to assess the effect of various priming agents for zirconia surface treatments. MATERIALS AND METHODS: A CAD/CAM system (Katana, Noritake Dental Supply) was used to fabricate 96 zirconia disks as a bonding substrate. The specimens were randomly divided into six groups (n = 16) and treated with one of the following acidic priming agents: Alloy Primer (ALP, Kuraray), Clearfil Ceramic Primer (CCP, Kuraray), Clearfil Photo Bond (CPB, Kuraray), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + Activator, Kuraray), Estenia Opaque Primer (EOP, Kuraray) and Porcelain Liner M Liquid A (PLA, Sun Medical). The specimens were bonded with an indirect composite material (Estenia C&B Dentin, Kuraray). Shear bond strengths were tested before and after 100 000 thermocycles and the data were analyzed by using the Steel-Dwass test and Mann-Whitney U-test. RESULTS: After 100 000 thermocycles, the PLA group showed the lowest bond strength (p = 0.010), whereas the CPB + Activator (23.9 MPa; p < 0.014) and CPB (22.7 MPa; p < 0.028) groups had significantly higher bond strengths than the other groups. The Mann-Whitney U-test revealed that bond strengths did not significantly decrease after thermocycling, except for specimens in the PLA (p = 0.038) and CCP (p = 0.028) groups. CONCLUSIONS: Application of a combination of hydrophobic phosphate monomer (MDP) and initiator results in a durable long-term bond between Katana zirconia and Estenia C&B composite material.


Assuntos
Cerâmica , Facetas Dentárias , Zircônio/química , Teste de Materiais , Microscopia Eletrônica de Varredura
14.
Clin Oral Implants Res ; 24(9): 977-84, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22713113

RESUMO

OBJECTIVES: To evaluate and compare the shear-bond strength of a gingiva-colored indirect composite material to three different implant framework materials (zirconia ceramics, gold alloy, and titanium), and to investigate the effect of surface pretreatment by air-particle abrasion and four priming agents. MATERIAL AND METHODS: A gingiva-colored indirect composite (Ceramage) was bonded to three framework materials (n = 80): commercially pure titanium (CP- Ti ), ADA (American Dental Association)-type 4 casting gold alloy (Type IV), and zirconia ceramics (Zirconia) with or without airborne-particle abrasion. Before bonding, the surface of the specimens was treated using no (control) or one of four priming agents: Alloy Primer (ALP), Estenia Opaque Primer (EOP), Metal Link Primer (MLP), and V-Primer (VPR). Shear-bond strength was determined after 24-h wet storage. Data were analyzed using Steel-Dwass for multiple comparisons, and Mann-Whitney U-test (P = 0.05). RESULTS: For both CP- Ti and Zirconia substrates, three groups, ALP, EOP, and MLP, showed significantly higher bond strengths (P < 0.05) than the other groups with or without airborne-particle abrasion. For Type IV substrates, significantly higher bond strengths were obtained in ALP and MLP groups (P < 0.01) compared with the other groups with airborne-particle abrasion. CONCLUSIONS: Application of priming agents containing specific phosphoric ester groups significantly enhances the bond strength of a gingiva-colored composite material to commercially pure titanium and zirconia frameworks. Combined use of a thione monomer with a phosphoric monomer enhances the bond strengths to airborne-particle abraded type IV gold alloy.


Assuntos
Colagem Dentária/métodos , Cimentos Dentários/química , Implantes Dentários , Facetas Dentárias , Ouro/química , Titânio/química , Zircônio/química , Cor , Corrosão Dentária , Análise do Estresse Dentário , Humanos , Metacrilatos/química , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Tionas/química , Triazinas/química
15.
Acta Odontol Scand ; 71(5): 1092-100, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23163257

RESUMO

OBJECTIVE: To evaluate shear bond strength of a gingiva-colored indirect composite to three implant framework materials, before and after thermocycling, and verify the effect of surface pre-treatment for each framework. MATERIALS AND METHODS: Commercially pure titanium (CP-Ti), American Dental Association (ADA) type 4 casting gold alloy (Type IV) and zirconia ceramics (Zirconia) were assessed. For each substrate, 96 disks were divided into six groups and primed with one of the following primers: Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Activator), Estenia Opaque Primer (EOP), Metal Link (MLP) and V-Primer (VPR). The specimens were then bonded to a gingiva-colored indirect composite (Ceramage Concentrate GUM-D). Shear bond strengths were measured at 0 and 20 000 thermocycles and data were analyzed with the Steel-Dwass test and Mann-Whitney U-test. RESULTS: Shear bond strengths were significantly lower after thermocycling, with the exception of Type IV specimens primed with CPB (p = 0.092) or MLP (p = 0.112). For CP-Ti and Zirconia specimens, priming with CPB or CPB+Activator produced significantly higher bond strengths at 0 and 20 000 thermocycles, as compared with the other groups. For Type IV specimens, priming with ALP or MLP produced higher bond strengths at 0 and 20 000 thermocycles. CONCLUSIONS: Shear bond strength of a gingiva-colored indirect composite to CP-Ti, gold alloy and zirconia ceramics was generally lower after thermocycling. Application of a hydrophobic phosphate monomer and polymerization initiator was effective in maintaining bond strength of CP-Ti and zirconia ceramics. Combined use of a thione monomer and phosphoric monomer enhanced the durable bond strength of gold alloy.


Assuntos
Implantes Dentários , Materiais Dentários , Gengiva , Humanos , Microscopia Eletrônica de Varredura , Osseointegração , Propriedades de Superfície
16.
J Oral Sci ; 54(1): 39-46, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22466885

RESUMO

The present study evaluated the effect of various surface treatments for zirconia ceramics on shear bond strength between an indirect composite material and zirconia ceramics. In addition, we investigated the durability of shear bond strength by using artificial aging (20,000 thermocycles). A total of 176 Katana zirconia disks were randomly divided into eight groups according to surface treatment, as follows: group CON (as-milled); group GRD (wet-ground with 600-grit silicon carbide abrasive paper); groups 0.05, 0.1, 0.2, 0.4, and 0.6 MPa (airborne-particle abrasion at 0.05, 0.1, 0.2, 0.4, and 0.6 MPa, respectively); and group HF (9.5% hydrofluoric acid etching). Shear bond strength was measured at 0 thermocycles in half the specimens after 24-h immersion. The remaining specimens were subjected to 20,000 thermocycles before shear bond strength testing. Among the eight groups, the 0.1, 0.2, 0.4, and 0.6 MPa airborne-particle abraded groups had significantly higher bond strengths before and after thermocycling. The Mann-Whitney U-test revealed no significant difference in shear bond strength between 0 and 20,000 thermocycles, except in the 0.2 MPa group (P = 0.013). From the results of this study, use of airborne-particle abrasion at a pressure of 0.1 MPa or higher increases initial and durable bond strength between an indirect composite material and zirconia ceramics.


Assuntos
Resinas Compostas , Colagem Dentária , Porcelana Dentária , Condicionamento Ácido do Dente , Abrasão Dental por Ar , Polimento Dentário , Análise do Estresse Dentário , Temperatura Alta , Metacrilatos , Poliuretanos , Distribuição Aleatória , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Fatores de Tempo , Zircônio
17.
Clin Oral Investig ; 16(5): 1401-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22139462

RESUMO

OBJECTIVES: This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks. MATERIALS AND METHODS: A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR-AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR-PO-AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR-PO-HF). Indirect composite (Estenia C&B) was bonded to zirconia specimens with no (CON) or one of four priming agents--Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)--with or without an opaque material (Estenia C&B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel-Dwass test and Mann-Whitney U test were used to compare shear bond strength. RESULTS: In ZR-AB specimens, the initial bond strength of the CPB and CPB + Activator groups was significantly higher as compared with the other three groups (P < 0.05), whereas the PLB and CPB + Activator groups had the highest pre- and post-thermocycling bond strengths in ZR-PO-AB and ZR-PO-HF specimens. Among CON disks without opaque material, bond strength was significantly lower in ZR-AB specimens than in ZR-PO-AB and ZR-PO-HF specimens (P < 0.05). CONCLUSION: Feldspathic porcelain coating of a Katana zirconia framework enhanced the bond strength of Estenia C&B indirect composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia. CLINICAL RELEVANCE: The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.


Assuntos
Colagem Dentária/métodos , Restauração Dentária Permanente/métodos , Condicionamento Ácido do Dente , Abrasão Dental por Ar , Silicatos de Alumínio , Desenho Assistido por Computador , Cimentos Dentários , Porcelana Dentária , Análise do Estresse Dentário , Metacrilatos , Poliuretanos , Compostos de Potássio , Cimentos de Resina , Zircônio
18.
Anticancer Res ; 22(2A): 545-57, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12014622

RESUMO

Dendritic cells (DCs) are antigen-presenting cells that initiate and modulate immune responses, including tumor immunity. In this study we examined, immunohistochemically, the distribution of DC subsets in the primary tumor, adjacent tissue and regional lymph nodes (RLNs) of patients with oral squamous cell carcinoma (OSCC). The numbers of S100+ and CD1a+ DCs in tissue adjacent to the primary tumor were greater in patients without metastasis to RLNs (PN- cases), compared with those with metastasis (PN+ cases), while greater numbers of CD83+ DCs in the primary tumors were found in PN+ cases. In the RLNs, the numbers of S100+ and CD1a+ DCs were less in PN+ cases than in PN- cases, while the numbers of CD83+ DCs were greater in PN+ cases compared with those in PN- cases. These results suggest that the distribution of DC subsets in OSCC may reflect the degree of tumor immunity induced in the host bearing OSCC.


Assuntos
Carcinoma de Células Escamosas/imunologia , Células Dendríticas/patologia , Neoplasias Bucais/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/metabolismo , Antígenos CD1/imunologia , Antígenos CD1/metabolismo , Carcinoma de Células Escamosas/patologia , Células Dendríticas/imunologia , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/imunologia , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Estadiamento de Neoplasias , Proteínas S100/imunologia , Proteínas S100/metabolismo
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