84 resultados para Próteses parciais removíveis
Resumo:
Due to advances in the manufacturing process of orthopedic prostheses, the need for better quality shape reading techniques (i.e. with less uncertainty) of the residual limb of amputees became a challenge. To overcome these problems means to be able in obtaining accurate geometry information of the limb and, consequently, better manufacturing processes of both transfemural and transtibial prosthetic sockets. The key point for this task is to customize these readings trying to be as faithful as possible to the real profile of each patient. Within this context, firstly two prototype versions (α and β) of a 3D mechanical scanner for reading residual limbs shape based on reverse engineering techniques were designed. Prototype β is an improved version of prototype α, despite remaining working in analogical mode. Both prototypes are capable of producing a CAD representation of the limb via appropriated graphical sheets and were conceived to work purely by mechanical means. The first results were encouraging as they were able to achieve a great decrease concerning the degree of uncertainty of measurements when compared to traditional methods that are very inaccurate and outdated. For instance, it's not unusual to see these archaic methods in action by making use of ordinary home kind measure-tapes for exploring the limb's shape. Although prototype β improved the readings, it still required someone to input the plotted points (i.e. those marked in disk shape graphical sheets) to an academic CAD software called OrtoCAD. This task is performed by manual typing which is time consuming and carries very limited reliability. Furthermore, the number of coordinates obtained from the purely mechanical system is limited to sub-divisions of the graphical sheet (it records a point every 10 degrees with a resolution of one millimeter). These drawbacks were overcome by designing the second release of prototype β in which it was developed an electronic variation of the reading table components now capable of performing an automatic reading (i.e. no human intervention in digital mode). An interface software (i.e. drive) was built to facilitate data transfer. Much better results were obtained meaning less degree of uncertainty (it records a point every 2 degrees with a resolution of 1/10 mm). Additionally, it was proposed an algorithm to convert the CAD geometry, used by OrtoCAD, to an appropriate format and enabling the use of rapid prototyping equipment aiming future automation of the manufacturing process of prosthetic sockets.
Resumo:
Composite materials have a wide application in various sectors, such as the medical field in the manufacture of prostheses, in automotive and aerospace. Thus it is essential to the development of new composite and a better understanding in the face of various loading conditions and service. Several structural elements are manufactured in the presence of geometric discontinuity (notch, hole, etc ) in their longitudinal sections and/or cross-cutting, and these affect the mechanical response of these elements. The objective is to study the mechanical response of laminated polymer matrix hybrid composites reinforced with glass fiber/jute in a uniaxial tensile test. The mechanical response takes in account both the influence of the presence of a geometric discontinuity (semicircular notches) and the orientation of fibers in the layers (anisotropy). The semicircular notches are located in longitudinal section (with a reduction in cross section) of the same. In this analysis, the anisotropy is characterized by types of configurations (with different orientations of fibers in the outer layers). A comparative study of mechanical properties with and without the presence of notches is developed. Both configurations consist of four layers of woven jute fiber bidirectional and a central layer of bidirectional woven glass fibers. In addition to the mechanical properties was also studied the characteristics of the fracture developed in each composite laminate. The results showed that in the comparative study, the anisotropy and the presence of semicircular notches directly influences the mechanical behavior of laminates composites, mainly in reducing the tensile strength, and well as the final characteristics of the fracture
Resumo:
Currently there is still a high demand for quality control in manufacturing processes of mechanical parts. This keeps alive the need for the inspection activity of final products ranging from dimensional analysis to chemical composition of products. Usually this task may be done through various nondestructive and destructive methods that ensure the integrity of the parts. The result generated by these modern inspection tools ends up not being able to geometrically define the real damage and, therefore, cannot be properly displayed on a computing environment screen. Virtual 3D visualization may help identify damage that would hardly be detected by any other methods. One may find some commercial softwares that seek to address the stages of a design and simulation of mechanical parts in order to predict possible damages trying to diminish potential undesirable events. However, the challenge of developing softwares capable of integrating the various design activities, product inspection, results of non-destructive testing as well as the simulation of damage still needs the attention of researchers. This was the motivation to conduct a methodological study for implementation of a versatile CAD/CAE computer kernel capable of helping programmers in developing softwares applied to the activities of design and simulation of mechanics parts under stress. In this research it is presented interesting results obtained from the use of the developed kernel showing that it was successfully applied to case studies of design including parts presenting specific geometries, namely: mechanical prostheses, heat exchangers and piping of oil and gas. Finally, the conclusions regarding the experience of merging CAD and CAE theories to develop the kernel, so as to result in a tool adaptable to various applications of the metalworking industry are presented
Resumo:
The present work has the main goal to study the modeling and simulation of a biphasic separator with induced phase inversion, the MDIF, with the utilization of the finite differences method for the resolution of the partial differencial equations which describe the transport of contaminant s mass fraction inside the equipment s settling chamber. With this aim, was developed the deterministic differential model AMADDA, wich was admensionalizated and then semidiscretizated with the method of lines. The integration of the resultant system of ordinary differential equations was realized by means of a modified algorithm of the Adam-Bashfort- Moulton method, and the sthocastic optimization routine of Basin-Hopping was used in the model s parameter estimation procedure . With the aim to establish a comparative referential for the results obtained with the model AMADDA, were used experimental data presented in previous works of the MDIF s research group. The experimental data and those obtained with the model was assessed regarding its normality by means of the Shapiro-Wilk s test, and validated against the experimental results with the Student s t test and the Kruskal-Wallis s test, depending on the result. The results showed satisfactory performance of the model AMADDA in the evaluation of the MDIF s separation efficiency, being possible to determinate that at 1% significance level the calculated results are equivalent to those determinated experimentally in the reference works
Resumo:
The semiarid rainfall regime is northeastern Brazil is highly variable. Climate processes associated with rainfall are complex and their effects may represent extreme situations of drought or floods, which can have adverse effects on society and the environment. The regional economy has a significant agricultural component, which is strongly influenced by weather conditions. Maximum precipitation analysis is traditionally performed using the intensity-duration-frequency (IDF) probabilistic approach. Results from such analysis are typically used in engineering projects involving hydraulic structures such as drainage network systems and road structures. On the other hand, precipitation data analysis may require the adoption of some kind of event identification criteria. The minimum inter-event duration (IMEE) is one of the most used criteria. This study aims to analyze the effect of the IMEE on the obtained rain event properties. For this purpose, a nine-year precipitation time series (2002- 2011) was used. This data was obtained from an automatic raingauge station, installed in an environmentally protected area, Ecological Seridó Station. The results showed that adopted IMEE values has an important effect on the number of events, duration, event height, mean rainfall rate and mean inter-event duration. Furthermore, a higher occurrence of extreme events was observed for small IMEE values. Most events showed average rainfall intensity higher than 2 mm.h-1 regardless of IMEE. The storm coefficient of advance was, in most cases, within the first quartile of the event, regardless of the IMEE value. Time series analysis using partial time series made it possible to adjust the IDF equations to local characteristics
Resumo:
The fauna of Brazilian reef fishes comprises approximately 320 species distributed along the coast of the mainland and islands ocean. Little is known about the levels of connectivity between their populations, but has been given the interest in the relations between the offshore and the islands of the Brazil, in a biogeographical perspective. The oceanic islands Brazilian hosting a considerable number of endemic species, which are locally abundant, and divide a substantial portion of its reef fish fauna with the Western Atlantic. Among the richest families of reef fish in species are Pomacentridae. This study analyzed through analysis of sequences of the mitochondrial DNA control region (D-loop), the standards-breeding population of C. Multilineata in different areas of the NE coast of Brazil, involving both oceanic islands (Fernando de Noronha Archipelago and of St. Peter and St. Paul) and continental shelf (RN and BA). To this aim, partial sequences were used in the region HVR1 of mtDNA (312pb). The population structure and parameters for the estimates of genetic variability, molecular variance (AMOVA), estimation of the index for fixing (FST) and number of migrants were determined. The phylogenetic relationships between the populations were estimated using neighbor-joining (NJ) method. A group of Bayesian analysis was used to verify population structure, according to haplotype frequency of each individual. The genetic variability of populations was extremely high. The populations sampled show moderate genetic structure, with a higher degree of genetic divergence being observed for the sample of the Archipelago of St. Peter and St. Paul. At smaller geographical scale, the sample of Rio Grande do Norte and the Archipelago of Fernando de Noronha do not have genetic differentiation. Three moderately differentiated population groups were identified: a population group (I), formed by the Rio Grande do Norte (I') and the archipelago of Fernando de Noronha (I''), and two other different groups formed by the island population of the archipelago of Saint Peter and St. Paul (II) and Bahia (III). The genetic patterns found suggest that the species has suffered a relatively recent radiation favoring the absence of shared haplotypes. C. multilineata seems to constitute a relatively homogenous population along the West Atlantic coast, with evidence of a moderate population genetic structure in relation to the Archipelago of St. Peter and St. Paul. These data supports the importance of the dispersal larvae by marine current and the interpopulation similarity this species.
Resumo:
For a complete comprehension of the effect of tooth loss is necessary to listen to the patients that have it. This study, of qualitative approach, investigate, in the dental history of users of SUS, listening to his/her experiences with the services of dental care, the reason that lead his/her to dental lost and the repercussion of this in his/her life. The collect of data was made by narrative interview, obeying to a pre-defined schema. The subjects interviewed were six (three of urban zone and three of rural zone), all of them were users of Family Health Units. The criterions of inclusion were the followings: the presence of tooth lost (total lost in both dental arch or in one of them, or partial lost in at least six elements in one of the arches); age between 25 and 59; male or female; to live in municipal district of São Tomé/RN or Natal/RN. Based on previous interviews was elaborated the odontological history of each patient. Such narratives, systemized in odontological history, were analyzed taking as base the studies of Souza71 and the proposal of Schutze, suggested for Jovchelovitch, Bauer34. The results show that toothache was the main reason for the search of odontological care. The patients confront the ache with home-made medicaments, allopathic ones, and searching for dental care. The searching for exodontics was stimulated for geographic access difficulties or for repressed demand, which as a result produced the aggravation of the lesions and the discredit in restoration s treatment. The self-care practice of tooth-brush with juá or toothpaste and the controlled ingestion of sugar was not sufficient to avoid dental lost. Guilty sentiments were identified in relation with lack of care with teeth. The acceptance of dental lost as a natural factor is an important motivation in lack of pain and in the belief that it was a simple part of life in old age. Life with dental prosthesis makes clear the difference between which was natural and which was unnatural, and difficulties with the prosthesis appeared. The limitation of the prosthesis in its functional aspect can be compensated by esthetic restitution, making possible smiling expression. Starting with this study and considering the high number of dental lost, mainly in low-rent population, which live with toothless limitations or bad-quality prosthesis which do not rehabilitate adequately, we suggested the realization of qualitative researches which include, also, another actors in heath care services such as professionals and administrators
Resumo:
Aim: To evaluate user satisfaction and quality of prosthetic treatments performed in specialized dental clinics (CEOs) of Natal Metropolitan Region - RN. Methods: Cross-sectional study with subjects who underwent prosthetic CEOs in the cities of Natal, Macaíba, Parnamirim and Sao Goncalo do Amarante in the period 2007 to 2009. Data collection was performed by questionnaire, clinical examination of the oral cavity and examination of fabricated denture. This analysis involved the following aspects: retention, stability, aesthetics and prosthesis fixation. The variables are presented by means of absolute numbers and proportions. The determination of the association between the independent and dependent variables was conducted by the association of Chi-square test and Fisher exact test. Results: A total of 149 users, totaling 233 conventional dentures (148 upper and 85 lower). Most patients (56.4%) were rehabilitated with conventional complete dentures. The technical quality of the denture was regarded as satisfactory in the majority (52.7%), whereas the inferior dentures were rated as unsatisfactory in 90.5% of cases. Satisfaction with the prosthesis was 69.1% (N = 103). The average time to begin treatment was 3 months to receive while the prosthesis was 4 months old. The presence of injury from the upper prosthesis occurred in 21.5% of cases (N = 32), candidiasis being the most frequent (N = 18). The technical quality of the upper prosthesis (p=0,041), as well as retention (p=0,002) and stability (p<0,001) were significantly associated with user satisfaction. Conclusions: The specialized Dental clinics has been fulfilling its role of providing treatment of intermediate complexity for low-income population with the majority of satisfield patients, even when their dentures have problems of technical quality
Resumo:
Nas últimas décadas, com a significativa redução da cárie dentária em crianças e adolescentes, uma maior atenção tem sido dada a outros problemas bucais como as oclusopatias. Em termos epidemiológicos no Brasil, esta tem ocupado o terceiro lugar dentre os problemas de saúde oral na população e, portanto, a inclusão destas como um problema de saúde pública se deve não apenas à sua alta prevalência, mas também ao impacto social, que interfere diretamente na qualidade de vida das pessoas. Diante do exposto é que este estudo objetiva buscar o impacto da presença e severidade das oclusopatias e suas respectivas necessidades de tratamento na qualidade de vida de adolescentes escolares de um município. Sendo assim, foram examinados 356 escolares na faixa etária de 15 -19 anos e determinadas a prevalência, severidade e necessidade de tratamento de oclusopatias através dos índices DAI, IOTN e ICON. O impacto sócio dentário das oclusopatias na qualidade de vida dos adolescentes foi analisado através do índice CS-OIDP. A fim de se verificar possíveis influências de variáveis estudadas na determinaçao do impacto na qualidade de vida das oclusopatias, estas serão coletadas através do estatus sócio-econômico, gênero, idade e tipo escola. Nos resultados parciais, relacionado a 50% da amostra, se observou uma maior prevalência do escolares de escola pública(68,1%), idade entre 15-16 anos(74,7%), gênero feminino(52,7%) e maior prevalência do SES baixo(77,5%). A análise estatística usando o teste qui-quadrado mostrou uma associação significativa do impacto da oclusopatia na qualidade de vida apenas quando avaliada com o índice ICON e o A-IOTN do examinado, comprovando uma associação da necessidade de tratamento com a presença do impacto na qualidade de vida. Com isso, busca-se comprovar e enfatizar a necessidade de se estabelecer políticas públicas que trabalhem na prevenção e interceptação dessas oclusopatias na população, melhorando, portanto, a qualidade de vida e saúde oral dos adolescentes.
Resumo:
Nas últimas décadas, com a significativa redução da cárie dentária em crianças e adolescentes, uma maior atenção tem sido dada a outros problemas bucais como as oclusopatias. Em termos epidemiológicos no Brasil, esta tem ocupado o terceiro lugar dentre os problemas de saúde oral na população e, portanto, a inclusão destas como um problema de saúde pública se deve não apenas à sua alta prevalência, mas também ao impacto social, que interfere diretamente na qualidade de vida das pessoas. Diante do exposto é que este estudo objetiva buscar o impacto da presença e severidade das oclusopatias e suas respectivas necessidades de tratamento na qualidade de vida de adolescentes escolares de um município. Sendo assim, foram examinados 356 escolares na faixa etária de 15 -19 anos e determinadas a prevalência, severidade e necessidade de tratamento de oclusopatias através dos índices DAI, IOTN e ICON. O impacto sócio dentário das oclusopatias na qualidade de vida dos adolescentes foi analisado através do índice CS-OIDP. A fim de se verificar possíveis influências de variáveis estudadas na determinaçao do impacto na qualidade de vida das oclusopatias, estas serão coletadas através do estatus sócio-econômico, gênero, idade e tipo escola. Nos resultados parciais, relacionado a 50% da amostra, se observou uma maior prevalência do escolares de escola pública(68,1%), idade entre 15-16 anos(74,7%), gênero feminino(52,7%) e maior prevalência do SES baixo(77,5%). A análise estatística usando o teste qui-quadrado mostrou uma associação significativa do impacto da oclusopatia na qualidade de vida apenas quando avaliada com o índice ICON e o A-IOTN do examinado, comprovando uma associação da necessidade de tratamento com a presença do impacto na qualidade de vida. Com isso, busca-se comprovar e enfatizar a necessidade de se estabelecer políticas públicas que trabalhem na prevenção e interceptação dessas oclusopatias na população, melhorando, portanto, a qualidade de vida e saúde oral dos adolescentes.
Resumo:
The aim of this study is to quantify the presence of major and minor elements in the sediments of estuary Potengi. Four georeferenced sampling points were used in the study, at which sediment samples were collected in the channel of the river and on the right and left banks. In addition, dissolved oxygen, salinity and water conductivity were taken in situ at the time of sample collection. The percentage of organic matter, determined by gravimetry, and granulometric analysis of the sediment samples were conducted in the laboratory. To quantify the major and minor elements a prior test to open the sample was conducted with standard NIST 1646ª estuarine sediment to choose the best methodology to be adopted. The sediment samples were dissolved in microwaves with nitric acid and chloridric acid, according to methodology proposed by US EPA 3051ª. Quantitative analyses of the elements Al, Fe, Cd, Cr, Cu, Mn, Ni, Pb and Zn were conducted by inductively coupled plasma optical emission spectrometry (ICPOES). The results showed that the partial concentrations of the elements analyzed are below average worldwide shale levels, the standard described by Turekian and Wedepohl (1961)
Resumo:
In this work we used chemometric tools to classify and quantify the protein content in samples of milk powder. We applied the NIR diffuse reflectance spectroscopy combined with multivariate techniques. First, we carried out an exploratory method of samples by principal component analysis (PCA), then the classification of independent modeling of class analogy (SIMCA). Thus it became possible to classify the samples that were grouped by similarities in their composition. Finally, the techniques of partial least squares regression (PLS) and principal components regression (PCR) allowed the quantification of protein content in samples of milk powder, compared with the Kjeldahl reference method. A total of 53 samples of milk powder sold in the metropolitan areas of Natal, Salvador and Rio de Janeiro were acquired for analysis, in which after pre-treatment data, there were four models, which were employed for classification and quantification of samples. The methods employed after being assessed and validated showed good performance, good accuracy and reliability of the results, showing that the NIR technique can be a non invasive technique, since it produces no waste and saves time in analyzing the samples
Resumo:
In this work calibration models were constructed to determine the content of total lipids and moisture in powdered milk samples. For this, used the near-infrared spectroscopy by diffuse reflectance, combined with multivariate calibration. Initially, the spectral data were submitted to correction of multiplicative light scattering (MSC) and Savitzsky-Golay smoothing. Then, the samples were divided into subgroups by application of hierarchical clustering analysis of the classes (HCA) and Ward Linkage criterion. Thus, it became possible to build regression models by partial least squares (PLS) that allowed the calibration and prediction of the content total lipid and moisture, based on the values obtained by the reference methods of Soxhlet and 105 ° C, respectively . Therefore, conclude that the NIR had a good performance for the quantification of samples of powdered milk, mainly by minimizing the analysis time, not destruction of the samples and not waste. Prediction models for determination of total lipids correlated (R) of 0.9955, RMSEP of 0.8952, therefore the average error between the Soxhlet and NIR was ± 0.70%, while the model prediction to content moisture correlated (R) of 0.9184, RMSEP, 0.3778 and error of ± 0.76%
Resumo:
The aim of this work was to study a series of 11 different compositions of Ti-Zr binary alloys resistance to aggressive environment, i. e., their ability to keep their surface properties and mass when exposed to them as a way to evaluate their performance as biomaterials. The first stage was devoted to the fabrication of tablets from these alloys by Plasma-Skull casting method using a Discovery Plasma machine from EDG Equipamentos, Brazil. In a second stage, the chemical composition of each produced tablet was verified. In a third stage, the specimen were submitted to: as-cast microstructure analysis via optical and scanning electron microscopy (OM and SEM), x-ray dispersive system (EDS) chemical analysis via SEM, Vickers hardness tests for mechanical evaluation and corrosion resistence tests in a 0.9% NaCl solution to simulate exposition to human saliva monitored by open circuit potential and polarization curves. From the obtained results, it was possible to infer that specimens A1 (94,07 wt% Ti and 5,93% wt% Zr), A4 (77,81 wt % Ti and 22,19 wt % Zr) and A8 (27,83 wt% Ti and 72,17 wt% Zr), presented best performance regarding to corrosion resistance, homogeneity and hardness which are necessary issues for biomaterials to be applied as orthopedic and odontological prosthesis
Resumo:
This work is combined with the potential of the technique of near infrared spectroscopy - NIR and chemometrics order to determine the content of diclofenac tablets, without destruction of the sample, to which was used as the reference method, ultraviolet spectroscopy, which is one of the official methods. In the construction of multivariate calibration models has been studied several types of pre-processing of NIR spectral data, such as scatter correction, first derivative. The regression method used in the construction of calibration models is the PLS (partial least squares) using NIR spectroscopic data of a set of 90 tablets were divided into two sets (calibration and prediction). 54 were used in the calibration samples and the prediction was used 36, since the calibration method used was crossvalidation method (full cross-validation) that eliminates the need for a validation set. The evaluation of the models was done by observing the values of correlation coefficient R 2 and RMSEC mean square error (calibration error) and RMSEP (forecast error). As the forecast values estimated for the remaining 36 samples, which the results were consistent with the values obtained by UV spectroscopy