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1.
Arq. bras. cardiol ; 119(4 supl.1): 115-115, Oct, 2022.
Artigo em Inglês | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1397216

RESUMO

BACKGROUND: Percutaneous mitral balloon commissurotomy (PMBC) remains the preferred treatment for patients with severe symptomatic rheumatic mitral stenosis (MS) and suitable anatomy. The objective of this study was to propose a new score for the prediction of immediate and late success. METHODS. This is a retrospective, single-center, single-arm registry encompassing all 1915 consecutive patients with rheumatic mitral stenosis recruited and referred to PMBC between August 3rd 1987 and July 19th 2010. All data were previously collected and recorded in a dataset. Clinical status was determined according to the New York Heart Association (NYHA) classification. Long-term outcome was a composite of incidence of major adverse cardiac events (cardiovascular death, new PMBC or mitral valve repair surgery) up to 24 years of clinical follow-up (from 1988 until December 3rd, 2011), including cardiovascular death, need for new PMBC, or mitral valve replacement surgery. RESULTS. Mean patient age was 36.8 ± 12.9 years, most (86.4%) were female, and Wilkins score was between 9-11 in 49.1% of patients. In the multivariate analysis, the predictors of immediate success were age (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.96-0.99; p=0.01), left atrium size (OR, 0.96; 95% CI, 0.93-0.99; p=0.01), mean pre-procedure mitral gradient (OR, 0.93; 95% CI, 0.89-0.96; p<0.001), intermediate Wilkins score 9-11 (OR, 0.62; 95% CI, 0.40- 0.94; p=0.02), and high Wilkins score ≥12 (OR, 0.35; 95% CI, 0.16-0.76; p<0.01). For prediction of late events, age (hazard ratio [HR], 0.98; 95% CI, 0.97-0.98; p<0.001), New York Heart Association class III-IV (HR, 1.50; 95% CI, 1.18-1.92; p<0.001), left atrium size (HR, 1.02; 95% CI, 1.02-0.04; p<0.01), and high Wilkins score ≥12 (HR, 2.02; 95% CI, 1.30-3.15; p<0.01) were significant. Two nomograms were developed using significant predictors from the model (one for immediate results and another for long-term results). CONCLUSIONS: In this large population, not only the Wilkins score, but also clinical and hemodynamic features, seem to be relevant in predicting immediate and late success for patients with rheumatic MS who underwent PMBC.


Assuntos
Hemodinâmica , Valva Mitral , Estenose da Valva Mitral
2.
Arq. bras. cardiol ; 117(5 supl. 1): 209-209, nov., 2021.
Artigo em Inglês | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1348789

RESUMO

INTRODUCTION: Percutaneous mitral balloon commissurotomy (PMBC) remains the preferred treatment for patients with severe symptomatic rheumatic mitral stenosis (MS) and suitable anatomy. OBJECTIVE: The objective of this study was to propose a new score for the prediction of immediate and late success. METHODS: This is a retrospective, single-center, single-arm registry encompassing all 1915 consecutive patients with rheumatic mitral stenosis recruited and referred to PMBC between August 3rd 1987 and July 19th 2010. All data were previously collected and recorded in a dataset. Clinical status was determined according to the New York Heart Association (NYHA) classification. Long-term outcome was a composite of incidence of major adverse cardiac events (cardiovascular death, new PMBC or mitral valve repair surgery) up to 24 years of clinical follow-up (from 1988 until December 3rd, 2011), including cardiovascular death, need for new PMBC, or mitral valve replacement surgery. RESULTS: Mean patient age was 36.8 ± 12.9 years, most (86.4%) were female, and Wilkins score was between 9-11 in 49.1% of patients. In the multivariate analysis, the predictors of immediate success were age (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.96-0.99; p = 0.01), left atrium size (OR, 0.96; 95% CI, 0.93-0.99; p = 0.01), mean pre-procedure mitral gradient (OR, 0.93; 95% CI, 0.89-0.96; p < 0.001), intermediate Wilkins score 9-11 (OR, 0.62; 95% CI, 0.40-0.94; p = 0.02), and high Wilkins score ≥12 (OR, 0.35; 95% CI, 0.16-0.76; p < 0.01). For prediction of late events, age (hazard ratio [HR], 0.98; 95% CI, 0.97-0.98; p < 0.001), New York Heart Association class III-IV (HR, 1.50; 95% CI, 1.18-1.92; p < 0.001), left atrium size (HR, 1.02; 95% CI, 1.02-0.04; p < 0.01), and high Wilkins score ≥12 (HR, 2.02; 95% CI, 1.30-3.15; p < 0.01) were significant. Two nomograms were developed using significant predictors from the model (one for immediate results and another for long-term results). CONCLUSIONS: In this large population, not only the Wilkins score, but also clinical and hemodynamic features, seem to be relevant in predicting immediate and late success for patients with rheumatic MS who underwent PMBC.


Assuntos
Valvuloplastia com Balão , Estenose da Valva Mitral
3.
J. invasive cardiol ; 32(6): 211-217, June, 2020. tab, graf
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1140579

RESUMO

Abstract: Objectives. Percutaneous mitral balloon commissurotomy (PMBC) remains the preferred treatment for patients with severe symptomatic rheumatic mitral stenosis (MS) and suitable anatomy. The objective of this study was to propose a new score for the prediction of immediate and late success. Methods. This is a single-center, retrospective analysis of all 1582 patients with severe mitral stenosis who underwent PMBC from August 1987 to July 2010. The composite outcome was cardiovascular death, new PMBC, or mitral valve repair surgery up to 24 years of follow-up. Results. Mean patient age was 36.8 ± 12.9 years, most (86.4%) were female, and Wilkins score was between 9-11 in 49.1% of patients. In the multivariate analysis, the predictors of immediate success were age (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.96-0.99; P=.01), left atrium size (OR, 0.96; 95% CI, 0.93-0.99; P=.01), mean preprocedure mitral gradient (OR, 0.93; 95% CI, 0.89-0.96; P<.001), intermediate Wilkins score 9-11 (OR, 0.62; 95% CI, 0.40-0.94; P=.02), and high Wilkins score ≥12 (OR, 0.35; 95% CI, 0.16-0.76; P<.01). For prediction of late events, age (hazard ratio [HR], 0.98; 95% CI, 0.97-0.98; P<.001), New York Heart Association class III-IV (HR, 1.50; 95% CI, 1.18-1.92; P<.001), left atrium size (HR, 1.02; 95% CI, 1.02-0.04; P<.01), and high Wilkins score ≥12 (HR, 2.02; 95% CI, 1.30-3.15; P<.01) were significant. Two nomograms were developed using significant predictors from the model. Conclusions. In this large population, not only the Wilkins score, but also clinical and hemodynamic features, seem to be relevant in predicting immediate and late success for patients with rheumatic MS who underwent PMBC.


Assuntos
Valva Mitral/cirurgia , Estenose da Valva Mitral , Hemodinâmica
4.
J Invasive Cardiol ; 32(6): 211-217, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32269178

RESUMO

OBJECTIVES: Percutaneous mitral balloon commissurotomy (PMBC) remains the preferred treatment for patients with severe symptomatic rheumatic mitral stenosis (MS) and suitable anatomy. The objective of this study was to propose a new score for the prediction of immediate and late success. METHODS: This is a single-center, retrospective analysis of all 1582 patients with severe mitral stenosis who underwent PMBC from August 1987 to July 2010. The composite outcome was cardiovascular death, new PMBC, or mitral valve repair surgery up to 24 years of follow-up. RESULTS: Mean patient age was 36.8 ± 12.9 years, most (86.4%) were female, and Wilkins score was between 9-11 in 49.1% of patients. In the multivariate analysis, the predictors of immediate success were age (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.96-0.99; P=.01), left atrium size (OR, 0.96; 95% CI, 0.93-0.99; P=.01), mean preprocedure mitral gradient (OR, 0.93; 95% CI, 0.89-0.96; P<.001), intermediate Wilkins score 9-11 (OR, 0.62; 95% CI, 0.40-0.94; P=.02), and high Wilkins score ≥12 (OR, 0.35; 95% CI, 0.16-0.76; P<.01). For prediction of late events, age (hazard ratio [HR], 0.98; 95% CI, 0.97-0.98; P<.001), New York Heart Association class III-IV (HR, 1.50; 95% CI, 1.18-1.92; P<.001), left atrium size (HR, 1.02; 95% CI, 1.02-0.04; P<.01), and high Wilkins score ≥12 (HR, 2.02; 95% CI, 1.30-3.15; P<.01) were significant. Two nomograms were developed using significant predictors from the model. CONCLUSIONS: In this large population, not only the Wilkins score, but also clinical and hemodynamic features, seem to be relevant in predicting immediate and late success for patients with rheumatic MS who underwent PMBC.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Estenose da Valva Mitral , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/diagnóstico , Estenose da Valva Mitral/cirurgia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
5.
Data Brief ; 29: 105311, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32211458

RESUMO

Data described in this article are related to the research article entitled "Amphotericin B-loaded Eudragit RL100 nanoparticles coated with hyaluronic acid (AMP EUD nanoparticles/HA) for the treatment of vulvovaginal candidiasis" [1]. In this work, we report original data on the statistical experimental design to formulate uncoated AMP EUD nanoparticles, data on the validation of spectrophotometric method to quantify the AMP released from uncoated EUD nanoparticles and coated with HA to obtain the in vitro drug release profiles as well as the drug encapsulation efficiency. In addition, we describe original data on characterization, including diameter size, polydispersity index, zeta potential, FTIR, DSC/TG, and XRD; data on diameter of in vitro inhibition halos of Candida albicans; and on the vaginal burden of infected animals treated with uncoated AMP EUD nanoparticles and AMP EUD nanoparticles/HA. Finally, different histological sections of endocervix collected from treated and untreated animals were inserted into this manuscript.

6.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(Suppl. 2b): 229-229, Jun. 2019.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1010342

RESUMO

INTRODUÇÃO: A valvuloplastia mitral percutânea por balão (VMP) continua sendo o tratamento preferencial para pacientes com estenose mitral (EM) reumática sintomática grave e com anatomia adequada. O objetivo deste estudo foi propor uma nova pontuação para predizer sucesso imediato e tardio. MÉTODOS: Trata-se de uma análise retrospectiva unicêntrica de todos os 1582 pacientes com estenose mitral grave submetidos à VMP de agosto de 1987 a julho de 2010 com valva nativa. O desfecho composto foi morte de origem cardiovascular, nova VMP ou cirurgia de reparo mitral até 24 anos de seguimento. RESULTADOS: A média de idade foi 36,8 ± 12,9 anos, a maioria do sexo feminino (86,4%), e o escore de Wilkins foi entre 9 e 11 (49,1%). Na análise multivariada, os preditores de sucesso imediato foram idade [OR (razão dos riscos): 0,98, IC (intervalo de confiança) 95%: 0,96-0,99, p = 0,01], tamanho do átrio esquerdo (OR: 0,96, IC95%: 0,93-0,99, p = 0,01) , gradiente mitral médio pré-procedimento do (OR: 0,93, IC95%: 0,89-0,96, p = 0,0001), Wilkins-score 9-11 (OR: 0,62, IC 95%: 0,40-0,94, p = 0,02) e Wilkins-score pontuação ≥ 12 (OR: 0,35, IC 95%: 0,16-0,76, p = 0,008). Para predição de eventos tardios, idade [RR (risco relativo): 0,98, IC 95%: 0,97-0,98, p = 0,0001], NYHA III-IV (RR: 1,50, IC 95%: 1,18-1,92, p = 0,0009), tamanho do átrio esquerdo (RR: 1,02; IC95%: 1,02-0,04; p = 0,003); Wilkins-score 9-11 (RR: 1,10; IC95%: 0,87-1,38; p = 0,40) e Wilkins-score ≥ 12 (RR: 2,02, IC 95%: 1,30-3,15, p = 0,001) foram significativos. Dois nomogramas foram desenvolvidos usando preditores significativos do modelo. Nós avaliamos a precisão preditiva do nomograma usando a curva ROC AUC e o nomograma foi calibrado. CONCLUSÕES: Nesta grande população, não apenas o escore estabelecido de Wilkins, mas também as características clínicas e hemodinâmicas, parecem ser relevantes na predição de sucesso imediato e tardio em pacientes com EM reumática submetidos à VMP. CONCLUSÕES: Nesta grande população, não apenas o escore estabelecido de Wilkins, mas também as características clínicas e hemodinâmicas, parecem ser relevantes na predição de sucesso imediato e tardio em pacientes com EM reumática submetidos à VMP. (AU)


Assuntos
Humanos , Valva Mitral , Estenose da Valva Mitral
7.
J Mater Sci Mater Med ; 27(1): 10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26676856

RESUMO

Intraocular delivery systems have been developed to treat many eye diseases, especially those affecting the posterior segment of the eye. However, ocular toxoplasmosis, the leading cause of infectious posterior uveitis in the world, still lacks an effective treatment. Therefore, our group developed an intravitreal polymeric implant to release clindamycin, a potent anti-Toxoplasma antibiotic. In this work, we used different techniques such as differential scanning calorimetry, thermogravimetry, X-ray diffraction, scanning electron microscopy, and fourier-transform infrared spectroscopy to investigate drug/polymer properties while manufacturing the delivery system. We showed that the lyophilization, hot molding process, and sterilization by gamma irradiation did not change drug/polymer physical-chemistry properties. The drug was found to be homogeneously dispersed into the poly lactic-co-glycolic acid (PLGA) chains and the profile release was characterized by an initial burst followed by prolonged release. The drug profile release was not modified after gamma irradiation and non-covalent interaction was found between the drug and the PLGA. We also observed the preservation of the drug activity by showing the potent anti-Toxoplasma effect of the implant, after 24-72 h in contact with cells infected by the parasite, which highlights this system as an alternative to treat toxoplasmic retinochoroiditis.


Assuntos
Antiprotozoários/administração & dosagem , Clindamicina/administração & dosagem , Raios gama , Temperatura Alta , Ácido Láctico , Ácido Poliglicólico , Toxoplasma/efeitos dos fármacos , Corpo Vítreo , Varredura Diferencial de Calorimetria , Linhagem Celular , Liofilização , Humanos , Microscopia Eletrônica de Varredura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
8.
Curr Eye Res ; 39(1): 99-102, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24325382

RESUMO

PURPOSE: To evaluate the in vivo release and ocular toxicity of a tacrolimus-loaded PLGA intravitreal implant. METHODS: Tacrolimus-loaded PLGA implants were inserted into the vitreous cavity of rabbits' eye. At different time points, the vitreous was retrieved and the concentration of tacrolimus released from the implants was determined. Clinical examination was performed to evaluate the implant tolerance. RESULTS: PLGA implants provided controlled and prolonged release of tacrolimus. Approximately 99.97% of the drug was released from the devices at 6 weeks. Ophthalmic examination revealed no evidence of toxic effects of implants. CONCLUSIONS: Tolerance and feasibility of the tacrolimus-loaded PLGA implants, as sustained intraocular drug delivery systems, were demonstrated.


Assuntos
Ácido Láctico/toxicidade , Ácido Poliglicólico/toxicidade , Próteses e Implantes/efeitos adversos , Tacrolimo/toxicidade , Uveíte/tratamento farmacológico , Animais , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/toxicidade , Corioide/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/efeitos adversos , Estudos de Viabilidade , Feminino , Imunossupressores/farmacologia , Imunossupressores/toxicidade , Injeções Intravítreas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Retina/efeitos dos fármacos , Esclera/efeitos dos fármacos , Tacrolimo/farmacologia , Corpo Vítreo/efeitos dos fármacos
9.
ROBRAC ; 21(57)out. 2012. ilus
Artigo em Português | LILACS | ID: lil-657318

RESUMO

Grande variedade de tratamento é indicada para dentes traumatizados, com fratura de esmalte e dentina, durante a infância e adolescência, dependente da quantidade de remanescente dentário. Dentre as possibilidades de tratamento para recuperação estética, funcional e biomecânica, materiais odontológicos que mimetizam propriedades das estruturas dentárias são almejados. Pinos de fibra de vidro tem sido cada vez mais utilizados pela capacidade de distribuir as tensões de forma favorável, minimizando o risco de fraturas em dentes com mínimo remanescente coronário, podendo ser associados à restaurações diretas e indiretas. O objetivo do presente relato de caso clínico é apresentar alternativa de tratamento com maior preservação de remanescente assegurando retenção do material restaurador, selamento do canal radicular e adequada longevidade de tratamento para dentes com fratura coronária com envolvimento de esmalte e dentina, em paciente hebiátrico.


Wide range of treatment is indicated for traumatized teeth with enamel and dentin fracture during childhood and adolescence, dependent on the amount of remaining. Among the treatment options for recovery aesthetic and functional biomechanics, dental materials that mimic properties of dental structures are desired. Glass fiber posts have been increasingly used for its ability to distribute stresses favorably, minimizing the risk of fractures in teeth with minimal remaining coronal, and may be associated with direct and indirect restorations. The purpose of this case report is to present an alternative treatment with greater preservation of remnant ensuring retention of the restorative material, sealing the root canal and adequate treatment for longevity of teeth with coronal fracture involving enamel and dentin of a hebiatric patient.

10.
ROBRAC ; 21(58)jul.-set. 2012. ilus
Artigo em Português | LILACS | ID: lil-676054

RESUMO

A colagem de fragmento dentário é alternativa estética e conservadora para dentes traumatizados. O objetivo deste trabalho foi realizar revisão sistemática da literatura científica de pesquisas clínicas que abordaram a colagem de fragmento dentário, compreendendo o período de 1955 até Março de 2012, associando-a a caso clínico para ilustrar técnica que parece ser adequada. Para a busca bibliográfica utilizou-se o site Pubmed/Medline com os seguintes descritores: "tooth fragment reattachment" e "dental bonding fragments". Foram obtidos 147 resumos, os quais foram lidos por dois revisores individualmente. Obtiveram-se 41 pesquisas laboratoriais, 6 pesquisas clínicas, 5 revisões de literatura e 94 casos clínicos. Porém, apenas 5 artigos foram considerados nesta revisão, de acordo com os critérios de inclusão e exclusão estabelecidos. Consideraram-se os seguintes aspectos: meio de armazenagem do fragmento, técnica de preparo do remanescente e do fragmento, materiais para a colagem e sucesso clínico. Adicionalmente, apresenta-se relato de caso clínico, de paciente de 8 anos de idade, envolvendo a colagem de fragmento após fratura coronária dos dentes 11 e 21 com acompanhamento clínico de 12 meses. Após avaliação sistemática da literatura, percebe-se que são poucos artigos que descrevem criteriosamente a técnica, abordando os critérios de interesse estabelecidos. A colagem de fragmento dentário demonstrou altas taxas de sucesso, principalmente nos primeiros 24 meses das avaliações clínicas. E parece ser eficaz quanto à manutenção da função mastigatória, à saúde periodontal e à satisfação do paciente. Além de conservadora, é fácil, rápida, de excelente resultado estético e funcional, resgatando ainda o equilíbrio emocional do paciente.


The tooth fragment reattachment is conservative and aesthetic alternative traumatized teeth. The aim of this study was realize systematic review of literature seeking clinical researches approaching of tooth fragment reattachment between the period of 1955 until 2012 march and associate it with a an clinical case, that illustrates a proper technique. For bibliographic search was used the PubMed / Medline website using the following keywords: "tooth fragment reattachment" and "dental bonding fragments." One hundread and forty seven abstracts were obtained, which were read by two reviewers, individually. Forty-one laboratorial researches, six clinical trials, five literature reviews and night-four clinical cases were obtained. However, only five were considered in this review, in accordance to the established inclusion and exclusion criteria. The following aspects were considered: medium storage of the fragment, preparation technique of dental remaining and fragment, bonding materials and clinical success. In addition, it was presented a case report of an 8 year old patient, involving the bonding of fragment after coronary fracture of teeth 11 and 21 with clinical follow up of 12 months. After systematic evaluation of the literature, it were found few articles with a careful description of the technique addressing the established interest criteria. The collage of fragments showed high success rates, especially in the first 24 months of clinical evaluations, and seems to be effective in maintenance of chewing, periodontal health and patient satisfaction. Besides being conservative, it's easy, fast, excellent both in cosmetic and functional outcome, and can also rescue the patient's emotional balance.

11.
Int J Artif Organs ; 34(2): 198-209, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21374562

RESUMO

PURPOSE: The transplant of retinal pigment epithelium (RPE) cells on supports may well be an effective therapeutic approach to improve the visual results of patients with age-related macular degeneration. In this study, two biodegradable polyurethanes were investigated as supports for human RPE cells (ARPE-19). METHODS: Polyurethane aqueous dispersions based on poly(caprolactone) and/or poly(ethylene glycol) as soft segments, and isophorone diisocyanate and hydrazine as hard segments were prepared. Polyurethane films were produced by casting the dispersions and allowing them to dry at room temperature for one week. The ARPE-19 cells were seeded onto the polyurethane films and they were investigated as supports for in vitro adhesion, proliferation, and uniform distribution of differentiated ARPE-19 cells. Additionally, the in vivo ocular biocompatibility of the polyurethane films was evaluated. RESULTS: The RPE adhered to and proliferated onto the polyurethane supports, thus establishing cell-PUD surface interactions. Upon confluence, the cells formed an organized monolayer, exhibited a polygonal appearance, and displayed actin filaments which ran along the upper cytoplasm. At 15 days of seeding, the occluding expression was confirmed between adjacent cells, representing the barrier functionality of epithelial cells on polymeric surfaces and the establishment of cell-cell interactions. Results from the in vivo study indicated that polyurethanes exhibited a high degree of short-term intraocular biocompatibility. CONCLUSIONS: Biodegradable polyurethane films display the proper mechanical properties for an easy transscleral-driven subretinal implantation and can be considered as biocompatible supports for a functional ARPE-19 monolayer.


Assuntos
Materiais Biocompatíveis , Proliferação de Células , Células Epiteliais/fisiologia , Poliuretanos/química , Epitélio Pigmentado da Retina/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Citoesqueleto de Actina/fisiologia , Animais , Adesão Celular , Diferenciação Celular , Linhagem Celular , Células Epiteliais/transplante , Feminino , Humanos , Hidrazinas/química , Imuno-Histoquímica , Isocianatos/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Poliésteres/química , Polietilenoglicóis/química , Ratos , Ratos Endogâmicos BN , Epitélio Pigmentado da Retina/transplante , Fatores de Tempo
12.
Indian J Dent Res ; 20(2): 153-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19553714

RESUMO

BACKGROUND: Post design and material has very important effects on dentinal stress distribution since the post placement can create stresses that lead to root fracture. MATERIALS AND METHODS: In this study we use finite element analysis (FEA) to evaluate stress distribution on endodontically treated maxillary central incisors that have been restored with different prefabricated posts. Six models were generated from the image of anatomical plate: Four metallic posts (ParaPost XH, ParaPost XT, ParaPost XP, and Flexi-Flange) and one fiberglass post (ParaPost Fiber Lux). The sixth model was a control-a sound maxillary central incisor. We used CAD software and exported the models to ANSYS 9.0. All the materials and structures were considered elastic, isotropic, homogeneous, and linear except the fiberglass post which was considered orthotropic. The values for the mechanical properties were obtained by a review of the literature and the model was meshed with 8-node tetrahedral elements. A load of 2N was applied to the lingual surface at an angle of 135 degrees. RESULTS: The stress results were recorded by shear stress and von Mises criteria; it was observed that there was no difference for stress distribution among the titanium posts in the radicular portions and into posts. There was higher stress concentration on the coronary portion with the titanium posts than with the glass fiber post. It seems that the metallic posts' external configuration does not influence the stress distribution. CONCLUSION: Fiber posts show more homogeneous stress distribution than metallic posts. The post material seems to be more relevant for the stress distribution in endodontically treated teeth than the posts' external configuration.


Assuntos
Planejamento de Prótese Dentária , Análise de Elementos Finitos , Incisivo/fisiopatologia , Maxila/fisiopatologia , Técnica para Retentor Intrarradicular/instrumentação , Silicatos de Alumínio/química , Fenômenos Biomecânicos , Resinas Compostas/química , Simulação por Computador , Desenho Assistido por Computador , Coroas , Materiais Dentários/química , Porcelana Dentária/química , Dentina/fisiopatologia , Elasticidade , Vidro/química , Humanos , Teste de Materiais , Modelos Biológicos , Compostos de Potássio/química , Software , Estresse Mecânico , Titânio/química , Raiz Dentária/fisiopatologia , Dente não Vital/fisiopatologia
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