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ITR e IPTU : o contraste entre as finalidades sociais e a gestão praticadaLEÃO, Celina Gontijo 14 December 2015 (has links)
A tributação é uma política pública determinante para a atuação do Estado, pois as demais políticas dependem da arrecadação dela resultante. Mas a tributação não é apenas fonte de custeio para o Estado; a forma como é realizada a gestão da tributação traz consequências diversas para a sociedade, a chamada função extrafiscal do tributo. Em ambas as feições, fiscal e extrafiscal, a política de tributação está submetida aos princípios constitucionais, dentre os quais se destacam a função social da propriedade e a contribuição conforme a capacidade contributiva que têm por finalidade alcançar o objetivo estatal de construção de uma sociedade mais justa e solidária. O objetivo deste trabalho é analisar a qualidade da tributação brasileira sob a ótica dos tributos ITR (imposto territorial rural) e IPTU (imposto sobre a propriedade predial e territorial urbana), desde a gestão legislativa até a gestão da fiscalização e da arrecadação, para verificar se estão sendo respeitados os princípios mencionados. A hipótese levantada é que o sistema tributário brasileiro é regressivo, isto é, um sistema no qual o cidadão que possui menor capacidade financeira é taxado de forma mais penosa do que aquele que acumula patrimônio, em especial, patrimônio imobiliário, pois é cobrado proporcionalmente mais tributos sobre o consumo do que sobre a propriedade. Essa característica estaria provocando consequências extrafiscais de concentração de patrimônio e de renda e o uso improdutivo do território, consequências contrárias ao objetivo constitucional da solidariedade e da função social da propriedade. Para fazer essa análise, por meio de revisão bibliográfica, no segundo capítulo será discutida a questão pano de fundo para o objetivo do trabalho que é saber qual a relação entre Estado e propriedade privada que justifica a tributação e se esta pode conduzir à solidariedade fiscal. A depender da resposta a essa indagação, pode-se implantar uma tributação que vise apenas arrecadar, independentemente de quem paga, ou uma tributação que considere todas as implicações sociais da cobrança de tributos. No terceiro capítulo será realizado o estudo dos princípios da função social da propriedade e da capacidade contributiva, as alterações de seus significados ao longo da história, suas previsões em outros países, para chegar à interpretação desses princípios que melhor realiza os objetivos estatais constitucionais. Por fim, nos capítulos quarto e quinto serão analisados os tributos sobre o patrimônio imobiliário, ITR e IPTU, para verificar se as suas incidências, na prática, respeitam os princípios constitucionais. De todo o exposto, conclui-se que a gestão da tributação no Brasil é ineficiente, contrária aos princípios a que deve obediência, pois a tributação sobre o patrimônio imobiliário não alcança os cidadãos que realmente apresentam capacidade contributiva, além de permitir o uso especulativo do solo urbano e rural, deixando as finalidades de moradia, alimentação e equidade em segundo plano. A atual política de tributação, fortemente regressiva, contribui para o aumento da desigualdade social no país e para a ausência de cidadania tributária da população brasileira. / The taxation is a crucial public policy to the performance of the State, because all other public policies depend on the revenues resulting from it. But taxation is not only the source of funding for the state; how taxation management performed brings several consequences for society, the function called extrafiscal tribute. In both features, fiscal and extrafiscal, taxation policy is subject to the constitutional principles, among which stand out the social function of property and the contribution as of the contributive ability which are intended to reach the state goal of building a society more justice and solidarity. The objective of this study is to analyze the quality of Brazilian taxation from the perspective of ITR (rural property tax) and IPTU (building and urban land ownership tax), from legislative management until the supervision and collection management, to ensure if they are respecting the principles mentioned. The hypothesis is that Brazilian tax is a regressive system, a system in which a citizen who has less financial capacity is tax more painfully than that accumulates assets, especially real estate heritage, because charges proportionately more taxes on consumption than on the property. This feature would be causing extrafiscal consequences of concentration of heritage and income and an unproductive use of land, consequences contrary to the constitutional goal of solidarity and the social function property. To do this analysis, through literature review, the second chapter will be discussed the issue backdrop for the purpose of work is to know what is the relationship between state and private ownership that justifies taxation and if this can lead to fiscal solidarity. Depending on the answer to that question, it can deploy a taxation aiming only raise, regardless of who pays, or taxation that considers all the social implications of tax collections. In the third chapter will be carried out the study of the principles of the social function of property and fiscal capacity, the changes their meanings throughout history, their predictions in others countries, to get the interpretation of these principles that better fulfills the constitutional state goals. Finally, in the fourth and fifth chapters will be reviewed taxes on real estate assets, ITR and IPTU, to check if its impact, in practice, respect the constitutional principles. From all the above, it is conclude that taxation management in Brazil is inefficient, contrary to the principles those should be obedience, because the taxation of real estate heritage does not reach the people who really have ability to pay, in addition to allowing the speculative use of urban and rural land, leaving the purposes of housing, feeding and equity in the background. The current taxation policy, highly regressive, contributes to increasing social inequality in the country and the absence of tax citizenship of the Brazilian population.
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Identificação e caracterização de elementos de transposição no genoma de Rhynchosciara / Identification e characterization of transposable elements in genome of RhynchosciaraTeixeira, Paula Rezende 18 April 2007 (has links)
Os elementos de transposição são seqüências discretas que são capazes de mover- se de um lócus para outro, constituindo uma parte significante do genoma de eucariotos. São agrupados em duas classes principais, os elementos da Classe I, que se transpõem via um intermediário de RNA (retrotransposon), e os elementos da Classe II, que se transpõem via mecanismo de DNA do tipo corta e cola (transposon). A análise das seqüências de um banco de cDNA construído com RNA mensageiro da glândula salivar de Rhynchosciara americana mostrou a presença de representantes das duas classes de elementos. Nesse trabalho caracteriza-se quarto elementos de transposição tipo mariner, onde as seqüências consenso de nucleotídeos foram derivadas de múltiplas cópias defectivas contendo deleções, mudança no quadro de leitura e códons de terminação. Ramar1, um elemento full-length e Ramar2 um elemento defectivo que contém uma deleção na região interna da ORF da transposase, mas mantém e as extremidades intactas. Ramar3 e Ramar4 são elementos defectivos que apresentam muitas deleções no interior da ORF. As seqüências preditas das transposases demostraram que Ramar1 e Ramar2 estão filogeneticamente muito próximos dos elementos mariner da subfamília mauritiana. Enquanto, Ramar3 e Ramar4 pertencem às subfamílias mellifera e irritans, respectivamente. Hibridização in situ mostrou que Ramar1 localiza-se em muitas regiões do cromossomo, principalmente na heterocromatina pericentromérica, enquanto Ramar2 aparece em uma única banda no cromossomo A. Resultado ainda mais curioso foi a caracterização molecular de um elemento de retrotransposição, denominado RaTART, que provavelmente é o responsável pela reconstituição telomérica em R.americana, assim como os elementos TART, HeT-A e TAHRE de Drosophila. Experimentos de Southern Blots do retroelemento RaTART indicam que este está representado por seqüências repetidas no genoma de R.americana, enquanto que Northern Blots mostraram uma expressão em diferentes estágios do desenvolvimento e o transcrito de alto peso molecular detectado representa o retrotransposon non-LTR inteiro. Enquanto a localização cromossômica de RaTART por hibridização in situ mostrou uma marcação predominante nas extremidades dos cromossomos, indicando possivelmente o primeiro elemento de transposição descrito em R.americana com função definida na estrutura do cromossomo. O último retrotransposon, identificado nesse projeto, presente no genoma de R.americana, denominado R2Ra, foi isolado a partir de uma varredura em um banco genômico construído no bacteriófago lambda dash usando como sonda o recombinante pRa1.4 que contém a unidade de repetição do rDNA. A análise da seqüência mostrou a presença de regiões conservadas, como o domínio de transcriptase reversa e o motivo zinc finger na região amino-terminal. O sítio de inserção no gene 28S do rDNA é altamente conservado em R.americana e a análise filogenética mostrou que este elemento pertence ao grupo R2. A localização cromossômica confirma que o elemento móvel R2Ra se insere em um sítio específico no gene rDNA. / Transposable elements are discrete sequences that are able to move from one locus to another within the genome, constituting a significant part of eukaryotic genome. They are grouped into two main types, Class I elements transpose via an RNA intermediate (retrotransposon), and Class II elements transpose via a DNA \"cut-and-paste\" mechanism (transposons). The analysis of sequences of a cDNA bank constructed from mRNA of the salivary glands of Rhynchosciara americana showed the presence of putative types of two classes elements. In the present thesis we describe four mariner elements, where the nucleotides consensus sequences were derived from multiple defective copies containing deletions, frame shifts and stop codons. Ramar1, a full-length element and Ramar2 is a defective mariner element that contains a deletion overlapping most of the internal region of the transposase ORF and the extremities of the element maintain intact. Ramar3 e Ramar4 are defective mariner element that were impossible to predict a complete ORF. Predicted transposase sequences demonstrated that Ramar1 and Ramar2 are phylogenetically very close to mariner-like elements of mauritiana subfamily. However, Ramar3 and Ramar4 belong to mellifera and irritans subfamilies, respectively. In situ hybridisations showed Ramar1 localized in several chromosome regions, mainly in pericentromeric heterochromatin and their boundaries, while Ramar2 appeared as a single band in chromosome A. More interesting data were the molecular characterization of the non-LTR retrotransposon element, called as RaTART, that probably is the responsible by telomeric reconstruction in R.americana, as well as the telomeric retrotransposable elements TART, Het-A and TAHRE of Drosophila. Southern blot analysis indicated that this transposable element is represented by repeat sequences in the genome of R. americana, and Northern blot analysis showed a expression in different developmental stages and the transcript of high molecular mass detected represents the full-length non-LTR retrotransposon. However, the chromosomal localization of the retroelement by in situ hybridisation showed a labelling predominant on chromosome ends, indicating possibly the first transposable element described in R.americana with a defined role in chromosome structure. The last retrotransposon, identified in this project, present in the genome of Rhynchosciara americana, called R2Ra, was isolated from screening of a lambda dash genomic library using as probe the recombinant pRa1.4 of rDNA. The analysis of sequence showed the presence of conserved regions, like transcriptase reverse domain and zinc finger motif in the amino terminal region. The insertion site is high conserved in R.americana and a phylogenetic analysis showed that this element belongs to the R2 clade. The chromosomal localization confirm that the R2Ra mobile element insert into the site specific in rDNA gene.
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Identificação e caracterização de elementos de transposição no genoma de Rhynchosciara / Identification e characterization of transposable elements in genome of RhynchosciaraPaula Rezende Teixeira 18 April 2007 (has links)
Os elementos de transposição são seqüências discretas que são capazes de mover- se de um lócus para outro, constituindo uma parte significante do genoma de eucariotos. São agrupados em duas classes principais, os elementos da Classe I, que se transpõem via um intermediário de RNA (retrotransposon), e os elementos da Classe II, que se transpõem via mecanismo de DNA do tipo corta e cola (transposon). A análise das seqüências de um banco de cDNA construído com RNA mensageiro da glândula salivar de Rhynchosciara americana mostrou a presença de representantes das duas classes de elementos. Nesse trabalho caracteriza-se quarto elementos de transposição tipo mariner, onde as seqüências consenso de nucleotídeos foram derivadas de múltiplas cópias defectivas contendo deleções, mudança no quadro de leitura e códons de terminação. Ramar1, um elemento full-length e Ramar2 um elemento defectivo que contém uma deleção na região interna da ORF da transposase, mas mantém e as extremidades intactas. Ramar3 e Ramar4 são elementos defectivos que apresentam muitas deleções no interior da ORF. As seqüências preditas das transposases demostraram que Ramar1 e Ramar2 estão filogeneticamente muito próximos dos elementos mariner da subfamília mauritiana. Enquanto, Ramar3 e Ramar4 pertencem às subfamílias mellifera e irritans, respectivamente. Hibridização in situ mostrou que Ramar1 localiza-se em muitas regiões do cromossomo, principalmente na heterocromatina pericentromérica, enquanto Ramar2 aparece em uma única banda no cromossomo A. Resultado ainda mais curioso foi a caracterização molecular de um elemento de retrotransposição, denominado RaTART, que provavelmente é o responsável pela reconstituição telomérica em R.americana, assim como os elementos TART, HeT-A e TAHRE de Drosophila. Experimentos de Southern Blots do retroelemento RaTART indicam que este está representado por seqüências repetidas no genoma de R.americana, enquanto que Northern Blots mostraram uma expressão em diferentes estágios do desenvolvimento e o transcrito de alto peso molecular detectado representa o retrotransposon non-LTR inteiro. Enquanto a localização cromossômica de RaTART por hibridização in situ mostrou uma marcação predominante nas extremidades dos cromossomos, indicando possivelmente o primeiro elemento de transposição descrito em R.americana com função definida na estrutura do cromossomo. O último retrotransposon, identificado nesse projeto, presente no genoma de R.americana, denominado R2Ra, foi isolado a partir de uma varredura em um banco genômico construído no bacteriófago lambda dash usando como sonda o recombinante pRa1.4 que contém a unidade de repetição do rDNA. A análise da seqüência mostrou a presença de regiões conservadas, como o domínio de transcriptase reversa e o motivo zinc finger na região amino-terminal. O sítio de inserção no gene 28S do rDNA é altamente conservado em R.americana e a análise filogenética mostrou que este elemento pertence ao grupo R2. A localização cromossômica confirma que o elemento móvel R2Ra se insere em um sítio específico no gene rDNA. / Transposable elements are discrete sequences that are able to move from one locus to another within the genome, constituting a significant part of eukaryotic genome. They are grouped into two main types, Class I elements transpose via an RNA intermediate (retrotransposon), and Class II elements transpose via a DNA \"cut-and-paste\" mechanism (transposons). The analysis of sequences of a cDNA bank constructed from mRNA of the salivary glands of Rhynchosciara americana showed the presence of putative types of two classes elements. In the present thesis we describe four mariner elements, where the nucleotides consensus sequences were derived from multiple defective copies containing deletions, frame shifts and stop codons. Ramar1, a full-length element and Ramar2 is a defective mariner element that contains a deletion overlapping most of the internal region of the transposase ORF and the extremities of the element maintain intact. Ramar3 e Ramar4 are defective mariner element that were impossible to predict a complete ORF. Predicted transposase sequences demonstrated that Ramar1 and Ramar2 are phylogenetically very close to mariner-like elements of mauritiana subfamily. However, Ramar3 and Ramar4 belong to mellifera and irritans subfamilies, respectively. In situ hybridisations showed Ramar1 localized in several chromosome regions, mainly in pericentromeric heterochromatin and their boundaries, while Ramar2 appeared as a single band in chromosome A. More interesting data were the molecular characterization of the non-LTR retrotransposon element, called as RaTART, that probably is the responsible by telomeric reconstruction in R.americana, as well as the telomeric retrotransposable elements TART, Het-A and TAHRE of Drosophila. Southern blot analysis indicated that this transposable element is represented by repeat sequences in the genome of R. americana, and Northern blot analysis showed a expression in different developmental stages and the transcript of high molecular mass detected represents the full-length non-LTR retrotransposon. However, the chromosomal localization of the retroelement by in situ hybridisation showed a labelling predominant on chromosome ends, indicating possibly the first transposable element described in R.americana with a defined role in chromosome structure. The last retrotransposon, identified in this project, present in the genome of Rhynchosciara americana, called R2Ra, was isolated from screening of a lambda dash genomic library using as probe the recombinant pRa1.4 of rDNA. The analysis of sequence showed the presence of conserved regions, like transcriptase reverse domain and zinc finger motif in the amino terminal region. The insertion site is high conserved in R.americana and a phylogenetic analysis showed that this element belongs to the R2 clade. The chromosomal localization confirm that the R2Ra mobile element insert into the site specific in rDNA gene.
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A Comparison of IRT and Rasch Procedures in a Mixed-Item Format TestKinsey, Tari L. 08 1900 (has links)
This study investigated the effects of test length (10, 20 and 30 items), scoring schema (proportion of dichotomous ad polytomous scoring) and item analysis model (IRT and Rasch) on the ability estimates, test information levels and optimization criteria of mixed item format tests. Polytomous item responses to 30 items for 1000 examinees were simulated using the generalized partial-credit model and SAS software. Portions of the data were re-coded dichotomously over 11 structured proportions to create 33 sets of test responses including mixed item format tests. MULTILOG software was used to calculate the examinee ability estimates, standard errors, item and test information, reliability and fit indices. A comparison of IRT and Rasch item analysis procedures was made using SPSS software across ability estimates and standard errors of ability estimates using a 3 x 11 x 2 fixed factorial ANOVA. Effect sizes and power were reported for each procedure. Scheffe post hoc procedures were conducted on significant factos. Test information was analyzed and compared across the range of ability levels for all 66-design combinations. The results indicated that both test length and the proportion of items scored polytomously had a significant impact on the amount of test information produced by mixed item format tests. Generally, tests with 100% of the items scored polytomously produced the highest overall information. This seemed to be especially true for examinees with lower ability estimates. Optimality comparisons were made between IRT and Rasch procedures based on standard error rates for the ability estimates, marginal reliabilities and fit indices (-2LL). The only significant differences reported involved the standard error rates for both the IRT and Rasch procedures. This result must be viewed in light of the fact that the effect size reported was negligible. Optimality was found to be highest when longer tests and higher proportions of polytomous scoring were applied. Some indications were given that IRT procedures may produce slightly improved results in gathering available test information. Overall, significant differences were not found between the IRT and Rasch procedures when analyzing the mixed item format tests. Further research should be conducted in the areas of test difficulty, examinee test scores, and automated partial-credit scoring along with a comparison to other traditional psychometric measures and how they address challenges related to the mixed item format tests.
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IMBALANCED HIGH DIMENSIONAL CLASSIFICATION AND APPLICATIONS IN PRECISION MEDICINEHui Sun (6630500) 14 May 2019 (has links)
<div>Classification is an important supervised learning technique with numerous applications. This dissertation addresses two research problems in this area. The first is multicategory classification methods for high dimensional data. To handle high dimension low sample size (HDLSS) data with uneven group sizes (i.e., imbalanced data), we develop a new classification method called angle-based multicategory distance-weighted support vector machine (MDWSVM). It is motivated from its binary counterpart and has the merits of both the support vector machine (SVM) and distance-weighted discrimination (DWD) methods while alleviating both the data piling issue of SVM and the imbalanced data issue of DWD. Theoretical results and numerical studies are used to demonstrate the advantages of our MDWSVM method over existing methods.</div><div><br></div><div>The second part of the dissertation is on the application of classification methods to precision medicine problems. Because one-stage precision medicine problems can be reformulated as weighted classification problems, the subtle differences between classification methods may lead to different application performances under this setting. Among the margin-based classification methods, we propose to use the distance weighted discrimination outcome weighted learning (DWD-OWL) method. We also extend the model to handle negative rewards for better generality and apply the angle-based idea to handle multiple treatments. The proofs of Fisher consistency for DWD-OWL in both the binary and multicategory cases are provided. Under mild conditions, the insensitivity of DWD-OWL for imbalanced setting is also demonstrated.</div>
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Infrared attenuated total reflection spectroscopy for monitoring biological systemsWang, Liqun 14 January 2009 (has links)
Mid-infrared (MIR) spectroscopy has been recognized as an important analytical technique, and is widely applied for qualitative and quantitative analysis of materials with an increasing interest in addressing complex organic or biologic constituents. In the presented thesis, (a) the fundamental principles for IR spectroscopic applications via in vivo catheters in combination with multivariate data analysis technique were developed, and (b) the combination with a second analytical technique ¨C scanning electrochemical microscopy (SECM) - for enhancing the information obtained at complex or frequently changing matrices was demonstrated.
The first part of this thesis focused on the combination of different MIR measurment techniques with specific focus on evanescent field absorption spectroscopy along with multivariate data analysis methods, for the discrimination of atherosclerotic and normal rabbit aorta tissues. Atherosclerotic and normal rabbit aorta tissues are characterized by marked differences in chemical composition governed by their water, lipid, and protein content. Strongly overlapping infrared absorption features of the different constituents and the complexity of the tissue matrix render the direct evaluation of molecular spectroscopic characteristics obtained from IR measurements challenging for classification. We have successfully applied multivariate data analysis and classification techniques based on principal component analysis (PCA), partial least squares regression (PLS), and linear discriminant analysis (LDA) to IR spectroscopic data obtained by infrared attenuated total reflectance (IR-ATR) measurements, reflection IR microscopy, and a recently developed IR-ATR catheter prototype for future in vivo diagnostic applications. Training and test data were collected ex vivo at atherosclerotic and normal rabbit aorta samples. The successful classification results at atherosclerotic and normal aorta samples utilizing the developed data evaluation routines reveals the potential of IR spectroscopy combined with multivariate classification strategies for in vitro, and ¨C in future - in vivo applications.
The second part of this thesis aimed at the development of a novel multifunctional analytical platform by combining SECM with single-bounce IR-ATR spectroscopy for in situ studies of electrochemically active or electrochemically induced processes at the IR waveguide surface via simultaneous evanescent field absorption spectroscopy. The utility of the developed SECM-IR-ATR platform was demonstrated by spectroscopically monitoring microstructured polymer depositions induced via feedback mode SECM experiments using a 25μm Pt disk ultramicroelectrode (UME). The surface of a ZnSe ATR crystal was coated with a thin layer of 2,5-di-(2-thienyl)-pyrrole (SNS), which was then polymerized in a Ru(bpy) ₃ ² ⁺-mediated feedback mode SECM experiment. The polymerization reaction was simultaneously spectroscopically monitored by recording the absorption intensity changes of specific IR bands characteristic for SNS, thereby providing information on the polymerization progress, mechanism, and level of surface modification.
Furthermore, a novel current-independent approach mechanism for positioning the UME in aqueous electrolyte solution was demonstrated by monitoring IR absorption changes of borosilicate glass (BSG) shielding the UME, and of water within the penetration depth of the evanescent field.
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Medical tax benefits to South African taxpayers : an overviewMoosa, R. 09 1900 (has links)
This study presents an overview of the medical expenditure allowed to taxpayers in the South African Income Tax Act, 58 of 1962 (hereafter the “Income Tax Act”). The study traces the changes made to the allowed expenditure over time. Changes made to the Income Tax Act, illustrating the effect of qualifying medical expenses on the income of persons with disabilities in terms of the Income Tax Act, are described. Certain provisions of the Income Tax Act, as well as other legislation dealing with persons with disabilities, were analysed. Furthermore, the research shows the effect of moderate to severe limitations on a person’s ability to claim qualifying medical expenses. In particular, the change over from the medical tax deduction system (section 18 of the Income Tax Act) to the medical tax rebate system (sections 6A and 6B of the Income Tax Act) to redress the inequality between high income and low income earners, was analysed. Case studies were used to illustrate that the medical tax deduction system (section 18 of the Income Tax Act) favoured high income earners over low income earners. Finally, the change over from the medical tax deductions (section 18 of the Income Tax Act) system to the current system of medical tax rebates (sections 6A and 6B of the Income Tax Act) was analysed. Except for a very small group of taxpayers, the medical tax rebate system (sections 6A and 6B of the Income Tax Act) was found to be financially more favourable to all taxpayers. / Taxation / M. Compt. (Taxation)
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Evaluation of fracture resistance of three post and core systems in endodontically treated teeth under loading to failure; and marginal gap measurement before and after cyclic loadingSaad, Amir N., 1979- January 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this study was to evaluate the fracture resistance of three post and core systems in endodontically treated teeth by loading to failure, and to measure marginal gaps before and after cyclic loading.
Sixty extracted canines were assigned to three groups. The groups tested were:
1) Single cast post and core (Group CP).
2) Prefabricated metal post and composite resin core (Group MR).
3) Glass fiber post and composite resin core (Group FR).
All teeth were obturated and prepared to receive a post and core with a coping.
Thirty teeth (10 from each group) were loaded to failure, and the other 30 teeth were fatigue-loaded. The marginal gaps on the facial and lingual surface of the fatigue-loaded group were measured before and after cyclic loading.
There were two hypotheses for this study. The first was that the FR group would have less marginal gap opening on the lingual surface than the other groups.
The second was that the CP group would have a higher load at failure than the other groups.
Group CP was found to have a significantly smaller pre-loading marginal gap than group FR (p = 0.0265) and group MR (p = 0.0273), while groups FR and MR did not have a significantly different pre-loading marginal gaps (p = 0.86). Group FR had significantly less change in marginal gap than group MR (p = 0.0013). Groups CP and MR did not have significantly different changes in marginal gap (p = 0.09). Groups CP and FR did not have significantly different changes in marginal gap (p = 0.11).
The three post types did not have significantly different maximum loads to failure (p= 0.49), moments of inertia at cervical area (p = 0.75), or moments of inertia at fracture site (p=0.12).
There was no significant difference between groups CP, FR, and MR in the load-to-failure test. Group CP demonstrated the highest load-to-failure values; however, the highest load-to-failure mean was for group MR. All fractures observed in this study were catastrophic. Group FR demonstrated better stress distribution and caused no early fractures in the fatigue-loading group.
All groups demonstrated significant marginal gap changes on the lingual surface after fatigue loading; however, group FR demonstrated <45 μm marginal gap opening. In group FR, the reduced marginal gap opening was attributed to the use of Panavia 21 with the proper surface treatments to bond to the tooth structure, the resin composite, and the metal coping.
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