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1.
Public Underst Sci ; : 9636625241254505, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38863437

RESUMO

Today, the dominant climate change discourses affirm its anthropogenic nature and the urgency for policies. However, minority discourses remain active in the worldwide debate, refining arguments beyond simple denial-as shown regarding formal/official discourses of the United States and European far-right parties. This makes it necessary to examine the public understanding of climate change in everyday, informal minority discourses, looking at how they work for broadening societal space for "quarantining" the transformative potential of climate change meanings/policies. For this, we analyze readers' comments on climate change articles from two Portuguese newspapers, drawing from the frameworks of neutralization techniques and meaning barriers. Findings show that although denial of anthropogenic climate change remains, discursive efforts concentrate on person-stigmatizing depictions of climate change actors, delegitimized as "elites" in populist vocabularies, reflecting a consistent alignment between everyday discourses and those of the United States and European official far-right. We discuss the functions this pattern may have for the growth of climate change minority positions.

2.
Sports Biomech ; 21(10): 1303-1311, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32727291

RESUMO

The paddling stroke rate (SR) is one of the key determinants of flat water kayak performance. The aim of this study was to analyse the way in which the kayak paddler changes the duration of the water and aerial phases due to the increase in stroke rate. Ten elite kayak paddlers (five males and five females) were analysed performing 200 m on-water trials in an individual kayak (K1), at four different stroke rates (60, 80, 100 strokes per minute and race pace). The duration of the water and aerial phases, SR and impulse were computed based on the data collected using the FPaddle system. Results corroborate the importance of reaching higher SR to increase kayak velocity (r = 0.904, p < 0.001). Both water and aerial phase durations correlated negatively with SR (r = -0.929, p < 0.001; R = -0.909, p < 0.001, respectively). However, with the first, the correlation was linear (r2 = 0.883), and for the second, the trend of relationship was curvilinear (r2 = 0.893). Due to differences in correlation, the results suggest that at high SR (above 120 strokes per minute) to continue increasing SR it will be more productive to reduce the duration of the water phase.


Assuntos
Esportes , Esportes Aquáticos , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Navios , Água
3.
Materials (Basel) ; 14(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34576635

RESUMO

The widespread application of innovative thermal enhanced façade solutions requires an adequate durability evaluation. The present work intends to assess the durability of a new aerogel cement-based rendering system through the adaptation of different accelerated aging cycles, such as heating-freezing, freeze-thawing, and heat-cold. Several mechanical properties and also capillary and liquid water absorptions were tested for uncoated and coated specimens. A decrease in the mechanical strength, especially after freeze-thaw cycles, was observed. However, the water action promoted the late hydration of the cement paste contributing to the densification of the matrix and, consequently, the increase of the adhesive strength. Additionally, a decrease in the dynamic modulus of elasticity and an increase in the Poisson's ratio were observed after aging, which indicates a higher capacity of the render to adapt to substrate movements, contributing to a reduction of cracking.

4.
Arch Ital Urol Androl ; 92(4)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33348961

RESUMO

PURPOSE: The aim of this study was to evaluate the clinical impact of perineural invasion (PNI) in prostate biopsy in patients submitted to radical prostatectomy and on active surveillance (AS). MATERIALS AND METHODS: We performed a single center, retrospective, cohort study on patients diagnosed with clinically localized prostate cancer and submitted to radical prostatectomy between January 2010 and December 2016. We evaluated clinical and anatomopathological characteristics from the biopsy and radical prostatectomy specimen and correlated with biochemical recurrence (BCR) using a survival analysis. We also evaluated the impact of PNI in patients with criteria for active surveillance. RESULTS: The cohort analyzed consists of 107 patients, with a mean age of 63.1 years and a mean PSA prior to biopsy of 7.8 ng/ml. In prostate biopsy, 66.4% of the patients had a Gleason score of 6, 30.9% had a Gleason score of 7, and 2.7% had a Gleason score of 8 or higher, with PNI being detected in 57 (53.3%) of the patients. Regarding the anatomopathological characteristics of the surgical specimen, invasion of the seminal vesicles was observed in 6.5%, lymph nodes involvement in 9.3% and positive surgical margins in 27.1% of the cases. During follow-up, BCR was recorded in 24.3% of cases. Clinicopathological features were stratified according to the presence or absence of PNI, with statistical significance in relation to the Gleason Score (p = 0.001), pathologic T stage (p = 0.001), D'Amico risk (p = 0.002) and upstaging of the Gleason score (p = 0.045). The survival analysis revealed a relationship between PNI and BCR (hazard ratio = 2.98; 95% CI: 1.36-6.58; p = 0.007). Regarding the men potentially eligible for AS, the presence of PNI on the biopsy presented a significant relation with Gleason upgrade (p = 0.004) and extraprostatic extension (p = 0.017). CONCLUSIONS: The presence of PNI in prostate biopsy is related to adverse anatomopathological factors, being a potential predictor of BCR and have a possible role in the selection of patients for AS.


Assuntos
Próstata/inervação , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Conduta Expectante , Idoso , Biópsia por Agulha , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Análise de Sobrevida
5.
Arch Ital Urol Androl ; 92(4)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33348973

RESUMO

The Doege-Potter syndrome is a rare paraneoplastic syndrome presenting with hypoglycaemia due to ectopic secretion of insulin-like growth factor II (IGF-II) from a solitary fibrous tumor. The underlying tumor can be benign or malignant and rarely present in extrapleural sites. We describe the case of a 83-year-old male diagnosed with a Doege-Potter syndrome due to a kidney tumor.


Assuntos
Hipoglicemia/etiologia , Neoplasias Renais/complicações , Síndromes Paraneoplásicas/etiologia , Idoso de 80 Anos ou mais , Humanos , Fator de Crescimento Insulin-Like II/biossíntese , Neoplasias Renais/metabolismo , Masculino , Síndromes Paraneoplásicas/metabolismo
6.
Rev Col Bras Cir ; 47: e20202469, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32491031

RESUMO

PURPOSE: The aim of this study was to evaluate the impact of penile rehabilitation in restoring erectile function in patients submitted to anterior resection of the rectum (ARR) or radical prostatectomy (RP), comparing the results between these two groups. MATERIALS AND METHODS: We performed a unicenter retrospective cohort study, on patients evaluated in our multidisciplinary oncosexology consultation, between January 2015 and January 2018, submitted to RP or ARR (males) and presenting sexual dysfunction. We evaluate the patient and oncologic characteristics, the type of sexual dysfunction, marital status, assessed the International Index of Erectile Function (IIEF-5) on the first and last consultation and the therapeutic approach. A statistical analysis was performed. RESULTS: A total of 55 patients were included, 60% (33) performed ARR and 40% (22) RP. Regarding the sexual dysfunction after surgery, erectile dysfunction (ED) was found in the majority of patients (>95%). On the initial IIEF-5 scoring, ARR and RP patients had, most frequently, severe or moderate ED (score 5-11), 78.8% and 59.1% respectively. When reassessed the IIEF-5 scoring of each patient during follow-up, there was an improvement in 69.7% of ARR patients and 72.7% of RP patients (p=0.81). Regarding the therapeutic approach, 84.8% of ARR patients used phosphodiesterase-5 inhibitors (PDE5I) exclusively, 3% used Alprostadil injection, while RP patients used 63.6% and 31.8%, respectively (p<0.05). CONCLUSIONS: Despite the technical differences of these surgeries, from the sexual point of view these patients benefit with a penile rehabilitation.


Assuntos
Alprostadil/uso terapêutico , Disfunção Erétil/reabilitação , Inibidores da Fosfodiesterase 5/uso terapêutico , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Agentes Urológicos/uso terapêutico , Adulto , Idoso , Disfunção Erétil/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Ereção Peniana/efeitos dos fármacos , Prostatectomia/efeitos adversos , Reto , Estudos Retrospectivos
8.
Rev. Col. Bras. Cir ; 47: e20202469, 2020. tab, graf
Artigo em Português | LILACS | ID: biblio-1136599

RESUMO

RESUMO Objetivo: O objetivo deste estudo foi avaliar o impacto da reabilitação peniana na recuperação da função erétil em pacientes submetidos a ressecção anterior do reto (RAR) ou a prostatectomia radical (PR), comparando os resultados entre esses dois grupos. Materiais e Métodos: Foi realizado estudo de coorte retrospetivo unicêntrico, em pacientes avaliados na nossa consulta multidisciplinar de oncosexologia, entre janeiro de 2015 e janeiro de 2018, submetidos a PR ou RAR (homens) com disfunção sexual. Avaliamos as características oncológicas dos pacientes, idade, estado civil, tipo de disfunção sexual, Índice Internacional de Função Erétil (IIEF-5) na primeira e última consulta e terapêutica utilizada. Foi realizada análise estatística. Resultados: Foram incluídos 55 pacientes, 60% (33) realizaram RAR e 40% (22) PR. Em relação à disfunção sexual após a cirurgia, a disfunção erétil (DE) foi encontrada na maioria dos pacientes (> 95%). Na pontuação inicial do IIEF-5, os pacientes com RAR e PR apresentaram, com maior frequência, DE moderada ou grave (escore 5-11), em 78,8% e 59,1% dos casos, respetivamente. Ao reavaliar a pontuação do IIEF-5 de cada paciente durante o acompanhamento, verificou-se melhoria em 69,7% dos pacientes com RAR e 72,7% dos pacientes com PR (p = 0,81). Quanto à abordagem terapêutica, 84,8% dos pacientes com RAR foram medicados com inibidores da fosfodiesterase-5 (PDE5I) exclusivamente e 3% com injeção de Alprostadil. Os pacientes com PR foram medicados com PDE5I em 63,6% e com injeção de Alprostadil em 31,8% (p <0,05). Conclusões: Apesar das diferenças técnicas destas cirurgias, do ponto de vista sexual, os pacientes se beneficiaram com a reabilitação peniana.


ABSTRACT Purpose: The aim of this study was to evaluate the impact of penile rehabilitation in restoring erectile function in patients submitted to anterior resection of the rectum (ARR) or radical prostatectomy (RP), comparing the results between these two groups. Materials and Methods: We performed a unicenter retrospective cohort study, on patients evaluated in our multidisciplinary oncosexology consultation, between January 2015 and January 2018, submitted to RP or ARR (males) and presenting sexual dysfunction. We evaluate the patient and oncologic characteristics, the type of sexual dysfunction, marital status, assessed the International Index of Erectile Function (IIEF-5) on the first and last consultation and the therapeutic approach. A statistical analysis was performed. Results: A total of 55 patients were included, 60% (33) performed ARR and 40% (22) RP. Regarding the sexual dysfunction after surgery, erectile dysfunction (ED) was found in the majority of patients (>95%). On the initial IIEF-5 scoring, ARR and RP patients had, most frequently, severe or moderate ED (score 5-11), 78.8% and 59.1% respectively. When reassessed the IIEF-5 scoring of each patient during follow-up, there was an improvement in 69.7% of ARR patients and 72.7% of RP patients (p=0.81). Regarding the therapeutic approach, 84.8% of ARR patients used phosphodiesterase-5 inhibitors (PDE5I) exclusively, 3% used Alprostadil injection, while RP patients used 63.6% and 31.8%, respectively (p<0.05). Conclusions: Despite the technical differences of these surgeries, from the sexual point of view these patients benefit with a penile rehabilitation.


Assuntos
Humanos , Masculino , Adulto , Idoso , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Alprostadil/uso terapêutico , Inibidores da Fosfodiesterase 5/uso terapêutico , Disfunção Erétil/reabilitação , Prostatectomia/efeitos adversos , Reto , Ereção Peniana/efeitos dos fármacos , Estudos Retrospectivos , Agentes Urológicos/uso terapêutico , Disfunção Erétil/etiologia , Pessoa de Meia-Idade
9.
J. coloproctol. (Rio J., Impr.) ; 38(4): 260-266, Oct.-Dec. 2018. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-975971

RESUMO

ABSTRACT Background: In the therapeutic decision about the malignant colon polyp, several factors predicting residual disease after the endoscopic resection guide the decision of surveillance or surgical intervention. This is a challenging decision, because even in the presence of high-risk predictors currently used, only 15-30% of the patients will have residual disease in the surgical specimen. Objective: To evaluate patients with a diagnosis of malignant colon polyp at the Hospital Center of São João, who were indicated for surgical treatment, studying the predictors of residual disease in the surgical specimen. Methods: A retrospective study was carried out, based on the patients with malignant colon polyp diagnosed and treated at the Hospital Center of São João in the city of Porto, Portugal, between 2009 and 2016. The endoscopic, anatomopathological, surgical and follow-up data were reviewed. Results: Of the total number of patients in the study (n = 96), 59 (61.5%) were indicated for surgery after a multidisciplinary discussion. Of this group, 21 patients (35.6%) had residual disease in the surgical specimen, with presence of lymph node invasion in 8 patients (13.6%). The presence of malignancy in the surgical resection specimen was statistically significantly associated with: size of the resected polyp (p = 0.023); sessile polyp (p = 0.007); piecemeal resection (p = 0.002). Conclusions: The persistence of malignancy in the surgical specimen was associated with larger sessile polyps and piecemeal removal. A significant number of patients did not show malignancy in the surgical resection specimen, with more markers being required to better stratify patients.


RESUMO Contexto: Na decisão terapêutica do pólipo maligno do cólon diversos fatores preditores de doença residual após a recessão endoscópica norteiam a decisão de vigilância ou intervenção cirúrgica. Esta é uma decisão desafiadora, uma vez que mesmo na presença dos preditores de alto risco usados atualmente, apenas 15% a 30% dos doentes terão doença residual na peça cirúrgica. Objetivo: Avaliar os doentes com diagnóstico de pólipo maligno do cólon no Centro Hospitalar de São João que foram orientados para tratamento cirúrgico, estudando os preditores de doença residual na peça cirúrgica. Métodos: Foi realizado um estudo retrospetivo, tendo por base os doentes com pólipo maligno do cólon diagnosticado e tratado no Centro Hospitalar de São João no Porto, Portugal, entre 2009 e 2016. Os dados endoscópicos, anatomopatológicos, cirúrgicos e o seguimento foram revistos. Resultados: Do total de doentes em estudo (n = 96); 59 (61,5%) tiveram indicação para cirurgia após discussão multidisciplinar. Deste grupo, 21 doentes (35,6%) apresentavam doença residual na peça cirúrgica, com presença de invasão ganglionar em 8 doentes (13,6%). A presença de malignidade na peça de ressecção cirúrgica associava-se de forma estatisticamente significativa a: tamanho do pólipo ressecado (p = 0,023); pólipo séssil (p = 0,007); ressecção em piecemeal (p = 0,002). Conclusões: A persistência de malignidade na peça cirúrgica associou-se a pólipos sésseis, de maiores dimensões e à remoção em piecemeal. Um número importante de doentes não apresentava malignidade na peça de ressecção cirúrgica, sendo necessários mais marcadores para melhor estratificar os doentes.


Assuntos
Humanos , Masculino , Feminino , Pólipos do Colo/terapia , Neoplasia Residual/cirurgia , Endoscopia , Neoplasias do Colo , Ressecção Endoscópica de Mucosa
10.
Sports Biomech ; 17(4): 453-461, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29160152

RESUMO

Using theoretical principles, the components of drag (friction D F, pressure D PR and wave D W) of a single-seat kayak were analysed. The purpose was to examine the effect of changes in wetted surface area due to changes in kayaker's weight and the relative contribution of D F, D PR and D W to the total passive drag as function of velocity. The total passive drag values were based on experimental data collected in a single-seat kayak. Three different kayaker simulated weights were tested - 65, 75 and 85 kg. D F was the drag component that contributed the greatest percentage (between 60 and 68% at 5.56 m/s the top velocity tested) to the total passive drag for all the velocities tested and simulated weights. D W was the most affected by the increase in kayaker's simulated weight, mainly when comparing 65/75 to 85 kg. Results support the importance of a kayak design selection that minimises the kayak's drag for the individual weight of the kayaker. Also, the results suggest that the path for better hydrodynamic kayak performance should seek changes that can reduce D F, D PR and D W with D F offering the most potential to reduce passive drag.


Assuntos
Hidrodinâmica , Equipamentos Esportivos , Esportes Aquáticos/fisiologia , Peso Corporal , Desenho de Equipamento , Fricção , Humanos , Masculino , Pressão
11.
Int J Prosthodont ; 31(1): 23­30, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29145529

RESUMO

PURPOSE: This study describes the development of a methodology for using three-dimensional (3D) image superimposition to measure volumetric changes in bone level around dental implants in comparison with linear measures. MATERIALS AND METHODS: The sample was comprised of 46 dental implants of 6-mm length and 4.1-mm diameter placed in the posterior maxilla and posterior mandible in 20 patients. All implants received screw-retained single crowns. Radiographic images were taken using cone beam computed tomography (CBCT) and digital periapical radiography after implantation and after 12 and 24 months of functional loading (after crown installation). Tridimensional reconstructions of the bone perimeter closest to the implant were developed, superimposed, and volumetrically measured. Linear measures of bone levels were recorded in periapical radiography images. A multilevel regression model tested volumetric and linear bone loss. RESULTS: The mean peri-implant linear bone loss for the first and second years was 0.2 ± 0.4 mm and 0.1 ± 0.2 mm, respectively, and the mean volumetric bone loss for the first and second years was 7.2 ± 6.1 mm³ and 6.4 ± 7.8 mm³, respectively. It was estimated that an increase of 1 mm of linear bone loss was associated with a mean volumetric bone loss of approximately 14 mm³ (P < .001). CONCLUSION: The findings showed that linear and volumetric bone loss measures are related. Measuring volumetric bone changes around implants is possible provided that the CBCT images have proper contrast and sharpness, particularly around the implant outline. Improvements in image quality and in the filters for bone tissue detection would be important for this methodology to be made faster and used clinically.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Implantação Dentária Endóssea , Implantes Dentários , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Interpretação de Imagem Radiográfica Assistida por Computador
12.
Water Sci Technol ; 75(12): 2916-2925, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28659532

RESUMO

The aim of this study was to evaluate the effect of water masses on the surface temperature with direct impact on the surrounding area. Three systems were used for the study: a fully vegetated system (subsurface flow constructed wetland (CW)), a lake with no vegetation and a lake partially vegetated with Lemna minor. Infrared thermography was applied for the different systems analysis, allowing the determination of the surface temperature spatial distribution. In general, the presence of plants and water in the analyzed systems contributed to lowering the surface temperatures when comparing to its surroundings. Differences up to about 22 °C were observed in the temperature between the CW canopy and the surrounding soil, and up to about 19 °C between the lake and the surrounding border. Different plant species (Canna flaccida, Canna indica and Zantedeschia aethiopica) inhabiting the CW were also compared and slightly higher average surface temperatures were observed for C. indica. The above mentioned results are relevant in terms of supporting a strategy for water systems inclusion, for example a lake or a CW, in a site as means of having influence in the surface temperature and to some extent in the heat island effect supporting a sustainable environmental management.


Assuntos
Biodegradação Ambiental , Temperatura , Áreas Alagadas , Água , Zingiberales
13.
J Appl Biomech ; 31(4): 258-63, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25838207

RESUMO

In sprint kayaking the role that paddling technique plays in optimizing paddle forces and resultant kayak kinematics is still unclear. The aim of this study was to analyze the magnitude and shape of the paddle force-time curve at different stroke rates, and their implications for kayak performance. Ten elite kayak paddlers (5 males and 5 females) were analyzed while performing 2000-m on-water trials, at 4 different paces (60, 80, and 100 strokes per minute, and race pace). The paddle and kayak were instrumented with strain gauges and accelerometers, respectively. For both sexes, the force-time curves were characterized at training pace by having a bell shape and at race pace by a first small peak, followed by a small decrease in force and then followed by a main plateau. The force profile, represented by the mean force/peak force ratio, became more rectangular with increasing stroke rate (F[3,40] = 7.87, P < .01). To obtain a rectangular shape to maximize performance, kayak paddlers should seek a stronger water phase with a rapid increase in force immediately after blade entry, and a quick exit before the force dropping far below the maximum force. This pattern should be sought when training at race pace and in competition.


Assuntos
Braço/fisiologia , Desempenho Atlético/fisiologia , Navios , Esportes/fisiologia , Aceleração , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Equipamentos Esportivos , Análise e Desempenho de Tarefas
14.
J Public Health Res ; 4(3): 589, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26753162

RESUMO

BACKGROUND: Modern societies spend most of their time indoors, namely at home, and the indoor environment quality turns out to be a crucial factor to health, quality of life and well-being of the residents. The present study aims to understand how indoor environment relates with quality of life and how improving housing conditions impacts on individuals' health. DESIGN AND METHODS: This study case will rely on the following assessments in both rehabilitated and non-rehabilitated social housing: i) field measurements, in social dwellings (namely temperature, relative humidity, carbon dioxide concentration, air velocity, air change rate, level of mould spores and energy consumption); ii) residents' questionnaires on social, demogaphic, behavioural, health characteristics and quality of life. Also, iii) qualitative interviews performed with social housing residents from the rehabilitated houses, addressing the self-perception of living conditions and their influence in health status and quality of life. All the collected information will be combined and analysed in order to achieve the main objective. EXPECTED IMPACT: It is expected to define a Predicted Human Life Quality (PHLQ) index, that combines physical parameters describing the indoor environment measured through engineering techniques with residents' and neighbourhood quality of life characteristics assessed by health questionnaires. Improvement in social housing should be related with better health indicators and the new index might be an important tool contributing to enhance quality of life of the residents. Significance for public healthThis study will contribute to understand how indoor environment relates with quality of life and how improving housing conditions impacts on individuals' health, in social housing neighbourhoods. As so, it is important to share the undertaken methodology carried out by a multidisciplinary team, in order to allow other researchers following comparable studies to adopt a similar approach. The case study results will allow to define building rehabilitation policies, improving residents' quality of life and adding great contribution to public health promotion.

15.
Rev. odonto ciênc ; 24(4): 420-425, Oct.-Dec. 2009. ilus, graf, tab
Artigo em Inglês | LILACS, BBO - odontologia (Brasil) | ID: biblio-873969

RESUMO

Purpose: To analyze the stress distribution on a cantilever-fixed partial denture after simulation of maximum mastication loads in order to optimize its design. Methods: A cantilever-fixed partial denture framework was designed in the CAD-CAM system Everest®Kavo v2.0 using two materials, titanium and zirconium, with connectors of 5.28 mm² and 9.05 mm², respectively. A finite element model was built for stress analysis using simulations of mastication load. Results: For zirconia, only the molar cantilever with the smaller connector area and a 0.5-mm fillet exceeded the considered threshold resistance value of 575 MPa. All the other designs yielded resistances below this value. For titanium, only cantilevers with 9.05 mm² connector area and fillets of 1 or 1.4 mm presented stress values inferior to titanium yield strengh. Conclusion: Within the limitations of this study, it can be concluded that titanium cantilever-fixed partial denture frameworks with a 5.28 mm² connector area cannot support maximum mastication loads; frameworks of this material require larger connectors with fillets introduced in the gingival embrasure. Zirconia, however, supports maximum bite forces in most situations with both molar and premolar design cantilevers. Precaution should be taken when dealing with smaller connectors of 5.28 mm².


Objetivo: Analisar a distribuição de tensões em próteses parciais fixas em cantilever após aplicação de cargas simuladoras da mastigação, de forma a otimizar o seu desenho. Metodologia: Obteve-se a infra-estrutura de uma prótese parcial fixa em cantilever no sistema CAD-CAM Everest®Kavo v2.0, considerando dois materiais: titânio e zircônia, com conectores de 5,28 mm² e 9,05 mm², respectivamente. Gerou-se um modelo de elementos finitos, onde foram efetuadas análises de tensões com cargas simuladoras da mastigação. Resultados: Para zircônia, apenas o cantilever molar com área de conector mais reduzida, e concordância de 0,5 mm, excedeu o valor de resistência 575 MPa. Para o titânio, apenas o cantilever de 9,05 mm², com concordâncias de 1 e 1,4 mm, apresentou valores inferiores à tensão do titânio. Conclusão: Dentro das limitações deste estudo pode-se concluir que as infra-estruturas de titânio em cantilever não suportam cargas mastigatórias máximas com uma área de conector de 5,28 mm² e requerem conectores de áreas superiores, com concordâncias introduzidas na embrasura gengival. A zircônia geralmente suporta forças mastigatórias máximas com cantilever molar ou pré-molar. Deve-se ter precaução quando a área dos conectores é reduzida para 5,28 mm².


Assuntos
Prótese Parcial Fixa , Titânio , Zircônio , Resistência à Tração
16.
Acta Med Port ; 17(2): 141-4, 2004.
Artigo em Português | MEDLINE | ID: mdl-15921644

RESUMO

The authors discuss the endoscopic techniques as an adjunctive in the evaluation and treatment of maxillo-facial fractures, particularly in the mandible, with special attention to the reduction and osteosynthesis near the condyle for those fractures with clear surgical indication. And also as a support in to the correct execution of the transbuccal techniques for treatment of body and angle fractures and in the repair of the orbital floor. The perspective of this work is the systematic search for quality, with diminution of iatrogenic effects and surgical risk, aims of modern surgery, even if with some technical difficulties and consumption of extra time, efforts.


Assuntos
Endoscópios , Fraturas Maxilares/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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