Tesi: "Confocal microscopy"

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Naredi-Rainer, Nikolaus. "Advanced confocal microscopy". Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-168349.

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Confocal microscopy is known for its capability to produce exceptional 3D images, even in living tissue. At the same time, it is a powerful spectroscopic tool, facilitating fluores- cence methods such as Fluorescence Correlation Spectroscopy (FCS) or single-molecule Förster Resonance Energy Transfer (FRET). It is heavily used to investigate a wide range of biological problems. This holds true especially for protein properties such as ligand binding, complex formation, conformational changes, or the intracellular distribution of the species in question. In this work, I will describe the assembly of two instruments: The first is a multi- parameter fluorescence detection (MFD) setup. It is a purely spectroscopic tool that offers the capability to characterize a fluorescent molecule, delivering information like fluorescence lifetime, anisotropy or the speed of its diffusion in free solution. When the molecule of interest is labelled with two fluorophores, additional information, like the energy transfer in-between them, becomes accessible and the correct distance between these two fluorophores can be calculated. If the two fluorophores are attached to different molecules, the MFD setup can detect interactions of these molecules in the range from pM up to μM with the help of Fluorescence Cross-Correlation Spectroscopy (FCCS). The second instrument, a stimulated emission depletion setup, combines some of the mentioned techniques, like FCS, with the superior image capability of a confocal micro- scope. One particular problem of fluorescent microscopes, though, is that image resolution is always restricted to the diffraction limit of the wavelength of the laser light. The STED setup utilizes the effect of stimulated emission in order to circumvent the diffraction bar- rier and allows images with a three-fold resolution increase, down to 75nm. These two setups will be used for several applications: The first will be centered around the molecular conformation of proteins, which are sensitive to the nature of the aqueous environment. In particular, the presence of ions can stabilize or destabilize (denature) protein secondary structure. The underlying mechanisms of these actions are still not fully understood. I will apply single-pair FRET to a small 29 amino acid long model peptide to investigate unfolding mechanisms of different unfolding reagents from the Hofmeister series, like sodium perchlorate or guanidinium chloride. The results show that certain salts, which are commonly summarized as denaturing agents, achieve the unfolding by either collapsing the molecule to a compressed state or swelling it to a denatured state. 7 The second application of the MFD setup is the investigation of the enhanced green fluorescent protein (EGFP). Although highly used in biochemistry and biophysics, for example to read out the expression level of genes, it is still not fully known what percentage of EGFP is fluorescent. This lack of knowledge makes it nearly impossible to make quantitative statements. With the help of FCCS, it is shown that the folding efficiencies range from 40 − 90%, depending on the environment of the fluorescent protein and which particular mutant is used. In the third application, the focus will be shifted to nucleation- and polymerization- behavior of actin. The actin cytoskeleton is a central mediator of cellular morphogenesis, and rapid actin reorganization drives essential processes such as cell migration and cell di- vision. In order to compare results of confocal spectroscopy methods with well-established bulk essays, we successfully ported the standard bulk essay to the confocal microscope, allowing for the first time to follow the decrease of monomer concentration and appear- ance of small filaments. Also, the formation of dimers or other small oligomers below the critical concentration is proven for the first time, using FCCS. The last application will utilize the STED setup in order to carry out the first steps towards the investigation of the nucleation and branching behavior of actin in cooperation with the actin related protein 2/3 (ARP2/3). This protein complex preferentially attaches to actin filaments that are located at the leading edge of a cell and forms branched filamentous structures. The exact conditions under which this process occurs are not well characterized. This part of the work will deal with the steps that are necessary to follow the polymerization process on the STED setup.

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Pacheco, Shaun, e Shaun Pacheco. "Array Confocal Microscopy". Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/623252.

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Confocal microscopes utilize point illumination and pinhole detection to reject out-of-focus light. Because of the point illumination and detection pinhole, confocal microscopes typically utilize point scanning for imaging, which limits the overall acquisition speed. Due to the excellent optical sectioning capabilities of confocal microscopes, they are excellent tools for the study of three-dimensional objects at the microscopic scale. Fluorescence confocal microscopy is especially useful in biomedical imaging due to its high sensitivity and specificity. However, all designs for confocal microscopes must balance tradeoffs between the numerical aperture (NA), field of view (FOV), acquisition speed, and cost during the design process. In this dissertation, two different designs for an array confocal microscope are proposed to significantly increase the acquisition speed of confocal microscopes. An array confocal microscope scans an array of beams in the object plane to parallelize the confocal microscope to significantly reduce the acquisition time. If N beams are used in the array confocal microscope, the acquisition time is reduced by a factor of N. The first design scans an array of miniature objectives over the object plane to overcome the trade-off between FOV and NA. The array of objectives is laterally translated and each objective scans a small portion of the total FOV. Therefore, the number of objectives used in the array limits the FOV, and the FOV is increased without sacrificing NA. The second design utilizes a single objective with a high NA, large FOV, and large working distance designed specifically for whole brain imaging. This array confocal microscope is designed to speed up the acquisition time required for whole brain imaging. Utilizing an objective with a large FOV and scanning using multiple beams in the array significantly reduces the time required to image large three-dimensional volumes. Both array confocal microscope designs use beam-splitting gratings to efficiently split one laser beam into a number of equal energy outgoing beams, so this dissertation explores design methods and analyses of beam-splitting gratings to fabrication errors. In this dissertation, an optimization method to design single layer beam-splitting gratings with reduced sensitivity to fabrication errors is proposed. Beam-spitting gratings are typically only designed for a single wavelength, so achromatic beam-splitting grating doublets are also analyzed for possible use in array confocal microscopes with multiple excitation wavelengths. An analysis of the lateral shift between grating layers in the achromatic grating doublet proves grating profiles with constant first spatial derivatives are significantly less sensitive than continuous phase profiles. These achromatic grating doublets have designed performance at two wavelengths, but the diffraction angles at the two wavelengths differ. To overcome that limitation, scale-invariant achromatic gratings are designed, which not only provide designed performance at two wavelengths, but also equal diffraction angles at two wavelengths.

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3

Ye, Peng. "Compressive confocal microscopy". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 50 p, 2009. http://proquest.umi.com/pqdweb?did=1889084501&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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4

Owen, Gabrielle M. "Coherence gated confocal microscopy". Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12434.

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Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1993.
Includes bibliographical references (leaves 33-34).
by Gabrielle M. Owen.
B.S.

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Sfalcin, Ravana Angelini 1985. "Avaliação de propriedades físico-químicas de infiltrantes experimentais com adição de partículas de vidro bioativas = Evaluation of the physical-chemical properties of experimental infiltrants incorporated with bioactive glass particles". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288423.

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Orientador: Americo Bortolazzo Correr
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo neste trabalho foi avaliar as propriedades físico-químicas de infiltrantes resinosos com adição de partículas bioativas, bem como sua capacidade de penetração e dureza da profundidade em lesões subsuperficiais de esmalte. Uma blenda contendo TEGDMA (75% em peso) e BisEMA (25% em peso) foi manipulada e a partir dela foram incorporados 5 tipos de partículas bioativas (10% em peso): hidroxiapatita (HAp), fosfato de cálcio amorfo (ACP), vidro bioativo policarboxilato de zinco (BAG Zn), vidro bioativo 45S5 (BAG 45S5), cimento de silicato de cálcio modificado por ?-TCP (HCAT-?). Um material comercial foi utilizado (ICON®) como controle. Dez espécimes foram confeccionados para cada grupo de cada teste: rugosidade superficial (Ra) antes e após a escovação; Resistência à flexão por 3 pontos (RF) e módulo de elasticidade (ME); resistência coesiva à tração (RC); dureza Knoop (KHN); densidade de ligação cruzada (DLC); grau de conversão (GC); sorção (S) e solubilidade (SL) em água; e micro-dureza (KHN). Os dados foram submetidos a ANOVA e teste Tukey (?=0.05). A penetração dos infiltrantes resinosos no esmalte humano desmineralizado foi qualitativamente avaliada em Microscopia Confocal de Varredura a Laser (n=5). Os resultados mostraram que os menores valores de rugosidade (antes e após a escovação foram apresentados pelo ACP. Com relação à resistência a flexão e módulo de elasticidade, T+B apresentou o maior valor e ICON® mostrou o menor valor. ICON® também mostrou o menor valor de resistência coesiva à tração; não houve diferença significativa entre os grupos T+B, HAp, ACP, BAG Zn, BAG 45S5 e HCAT-?. Para o teste de dureza Knoop, ICON® obteve o menor valor e BAG Zn mostrou o maior valor. Para densidade de ligação cruzada, ICON® apresentou maior quantidade de ligação cruzada e HAp, menor quantidade de ligação cruzada. ICON® apresentou grau de conversão significantemente menor que os infiltrantes experimentais, que não diferiram entre eles. ICON® apresentou a maior sorção de água e HAp a menor. Não houve diferença significativa entre os demais grupos. Para solubilidade, ICON® apresentou os maiores valores, mas sem diferença de ACP. BAG 45S5 apresentou a menor solubilidade. Com relação a micro-dureza, não houve diferença estatisticamente significante entre as profundidades avaliadas (50 µm, 200 µm, 350 µm e 500 µm). BAG 45S5, BAG Zn e HCAT-? não mostraram diferença estatística entre eles. Entretanto, HCAT-? e BAG Zn foram similares ao ICON® e ACP. O grupo cariado mostrou menor valor quando comparado a todos os grupos testados. A análise em microscopia confocal mostrou que todos os materiais apresentaram boa capacidade de penetração nas lesões iniciais, exceto para FCA. Pôde ser concluído que adição de partículas bioativas em um infiltrante experimental melhorou as propriedades mecânicas e não afetou a capacidade de penetração dos infiltrantes. O infiltrante resinoso contendo fosfato de cálcio amorfo foi o que apresentou o melhor desempenho no teste de rugosidade de superfície antes e após a escovação
Abstract: The aim of this study was to evaluate the physical-chemical properties of the experimental infiltrants with the addition of bioactive particles as well as their capability of penetration and depth Knoop hardness into caries-like lesions. A control blend was made with TEGDMA (75 wt%) and BisEMA (25 wt%). Five bioactive fillers were added in the control blend (10 wt%): Hydroxyapatite (Hap), amorphous calcium phosphate (ACP), Zinc-polycarboxylated bioactive glass (BAG-Zn), bioactive glass 45S5 (BAG 45S5), and ?-TCP modified calcium silicate cements (HCAT-?). An available commercially material was used (ICON®). Ten specimens were comprised by each group for the following tests: Surface roughness (Ra) before and after brushing abrasion; flexural strength (FS) and elastic modulus (E-Modulus); tensile cohesive strength (TCS); Knoop hardness (KHN); softnening ratio (SR); degree of conversion (DC); water sorption (WS) and solubility (SL); and micro-hardness (micro-KHN). Data were subjected to ANOVA and Tukey¿s test (?=0.05). Confocal Scanning Laser Microscopy was used to evaluate qualitatively the penetration capability of resin infiltrants into demineralized human enamel. Results showed that ACP had the lowest Ra before and after brushing abrasion. Regarding to the FS and E-modulus, T+B showed the higher value and ICON® showed the lower value. Also, ICON® showed the lower value of TCS, but there was no significant statistically difference among the groups T+B, HAp, ACP, BAG Zn, BAG 45S5 e HCAT-?. To the KHN, ICON® obtained the lower value and BAG Zn showed the higher value. According to the SR, ICON® showed lower SR and HAp, the higher SR. ICON showed DC significantly lower than experimental resin infiltrants. Regarding to the WS, ICON® presented the highest water sorption and HAp the lowest one. There was no significant statistically difference among the other groups. ICON showed the highest SL results; however, the results were similar to ACP. The lowest SL was found for BAG 45S5. Regarding to the micro-KHN, there was no statistically difference among the analyzed depths (50 µm, 200 µm, 350 µm and 500 µm). BAG 45S5, BAG Zn and HCAT- ? did not show statistical difference among them. However, HCAT- ? and BAG Zn were similar to ICON® and ACP. Carious group showed lower value when compared to all the tested groups. Confocal microscopy analysis showed good capability of penetration into the initial lesions for all materials, except for ACP. It could be concluded that the addition of bioactive particles into an experimental infiltrant improved the mechanical properties and did not affect the capability of penetration into the experimental infiltrants. The resin infiltrant with amorphous calcium phosphate presented the best performance to the roughness surface before and after brushing abrasion
Doutorado
Materiais Dentarios
Doutora em Materiais Dentários

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Booth, Martin J. "Adaptive optics for confocal microscopy". Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393566.

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Carlini, A. R. "Imaging modes of confocal scanning microscopy". Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233485.

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Alawadhi, Fahimah. "Statistical image analysis and confocal microscopy". Thesis, University of Bath, 2001. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341639.

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Lewin, Erland. "Approaches to Optimizing High Content Confocal Microscopy". Licentiate thesis, KTH, Applied Physics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10691.

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This thesis presents two methods for improving high contentconfocal microscopy.

The author's part in the first, "Toward a confocal subcellular atlasof the human proteome" was automating image capture of foursimultaneously tagged structures in cells in 96 well plates. In total,thousands of images of hundreds of proteins in cells. The authorwas also part of deciding which imaging methods should be used tomaximize image information content and quality, given the limitedtime available per well in order to scan large numbers of wells.

The second project, "Improved water permeability measurementsbased on fluorescence normalization" involves increasing the sensitivityof measurements of protein function by normalizing with anestimate of the amount of protein in the cell - the fluorescentsignal of a co-transfected protein. This could lead to achievingsufficient confidence in measurements with fewer experiments(thus increasing the information content in each experiment). Asurprisingly high level of noise in the relationship between thefluorescent signal and the protein function was measured.

Denna avhandling presenterar två projekt för att förbättrametoder för experiment med stora informationsmängderbaserade på konfokalmikroskopi.

Författarens del i det första projektet, "Toward a ConfocalSubcellular Atlas of the Human Proteome" (Mot en konfokal,subcellulär atlas av det mänskliga proteomet) var att automatiserabildinsamlingen av fyra samtidigt inmärkta strukturer i celler iplattor med 96 brunnar. Sammanlagt togs tusentals bilder avhundratals proteiner i celler. Författaren var även del i att fastställavilka bildinsamlingsmetoder som skulle användas för att maximeramängd och kvalitet på bild-informationen givet den begränsade tidper brunn som var tillgänglig för att kunna avbilda många brunnar.

Den andra studien, "Improved water permeability measurementsbased on fluorescence normalization" (Förbättrade vattenpermeabilitetsmätningargenom normalisering av fluorescens) syftade till att ökakänsligheten hos mätningar av proteiners funktion genom attnormalisera mätningarna med signalen från fluorescensen från ettkotransfekterat protein. Det skulle kunna leda till att nå tillräckligtillförlitlighet i mätresultaten med färre experiment (därmed ökainformationsinnehållet i varje experiment). En förvånansvärt högbrusnivå i förhållandet mellan fluorescenssignalen ochproteinfunktionen uppmättes

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Apeldoorn, Aart Alexander van. "Confocal Raman microscopy applications in tissue engineering /". Enschede : University of Twente [Host], 2005. http://doc.utwente.nl/50895.

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Jenkins, Matthew. "Quantitative confocal microscopy of dense colloidal systems". Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/1347.

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This document describes an experimental investigation into dense collections of hard spherical particles just large enough to be studied using a light microscope. These particles display colloidal properties, but also some similarities with granular materials. We improve the quantitative analysis of confocal micrographs of dense colloidal systems, which allows us to show that methods from simulations of granular materials are useful (but not sufficient) in analysing colloidal systems, in particular colloidal glasses and sediments. Collections of spheres are fascinating in their own right, but also make convincing models for real systems. Colloidal systems undergo an entropy-driven fluid-solid transition for hard spheres and a liquid-gas transition for suitable inter-particle attraction. Furthermore, experimental colloidal systems display a so far not well-understood glass transition at high densities, so that the equilibrium state is not achieved. This may be due to limited experimental timescales, but experiments under reduced gravity (both using the Space Shuttle and densitymatching solvents) suggest that it is not. Most colloidal studies have used scattering (i.e. non-microscopical) techniques, which provide no local information. Microscopy (particularly confocal) allows individual particles and their motion to be followed. However, quantitative microscopy of densely-packed, solidlyfluorescent particles, such as colloidal glasses, is challenging. We report, to our knowledge for the first time, a quantitative measure of confidence in individual particle locations and use this measure in an iterative best-fit procedure. This method was crucial for the investigation of the colloidal samples reported in this thesis. One of the disadvantages of microscopy is that it requires particles too large to be truly colloidal; gravity is no longer negligible. The particles used here rapidly sediment to form solid ”plugs”, which are supposedly ”random close packed” (RCP). At least in some cases, this is not the case, since some particles remain free to move. This observation, as well as some literature results, suggest that gravity has some influence on the structure of the sediment. In this document we consider some ideas from literature not normally considered in colloidal studies. Firstly, we discuss the RCP state, and the preferred Maximally Random Jammed state. Secondly, we borrow a technique designed to identify structures known as bridges in simulations of granular materials. Finding bridges, i.e. structures stable against gravity, in colloidal samples is the primary aim of this thesis. Gravity is important in colloidal sphere packings both in sediments and in glasses; its effect is not known but the best available candidate is bridging. The basic results of this analysis, the bridge size distributions, are close to those for granular systems, but differ little for samples of different volume fractions. We identify important stages of the analysis which require more investigation. Whilst questioning the usefulness of the bridge properties, we identify some related packing properties which show interesting trends. No theoretical predictions exist for these quantities. We investigated initially a non-density-matched system, but compare our results with a nearly density-matched system. The results from both systems are similar, despite the particles apparently acquiring a charge in the latter case. This thesis shows that reliable confocal microscopy of very dense systems of solidly-fluorescent particles is possible, and provides a range of unreported properties of dense sedimenting and sedimented nearly-Brownian sphere packings. It provides several suggestions for further analysis of these experimental systems, as well as some to be performed by those who simulate granular matter.

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Duranza, Sonia. "Three-dimensional image analysis using confocal microscopy". FIU Digital Commons, 1998. http://digitalcommons.fiu.edu/etd/3106.

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This thesis introduces imaging algorithms for three-dimensional data analysis and classification using confocal microscopy. The third dimension, depth information, is provided through the optical sectioning property of the confocal microscope. The theme of this thesis is to develop imaging techniques that extend beyond the traditional two-dimensional (2-D) spatial coordinate system into an augmented three-dimensional (3-D) world where analysis, interpretation, and the eventual classification of data is greatly enhanced. In the development of the proposed 3-D algorithms, three main objectives were sought: (1) establish proper 3-D mathematical extensions and practical implementations of 2-D standard formulations; (2) ensure that the process of classification overcomes the burden imposed by dependence in size and orientation through applications of the principal component transform and the log-spherical plot; and (3) address such issues as memory management and accelerated processing to reach the final objective of data recognition and classification effectively.

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Pankajakshan, Praveen. "Blind deconvolution for confocal laser scanning microscopy". Nice, 2009. http://www.theses.fr/2009NICE4057.

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La microscopie confocale à balayage laser est une technique puissante pour étudier les spécimens biologiques en trois dimensions (3D) par sectionnement optique. Bien qu’ubiquitaire, il persiste des incertitudes dans le procédé d’observations. Comme la réponse du système à l’impulsion, ou fonction de flou (PSF), est dépendante à la fois du spécimen et des conditions d’acquisition, elle devrait être estimée à partir des images observées avec l’objet. Ce problème est mal posé, sous déterminé, et comme le processus de mesure est quasi-aléatoire dans la nature, nous le traitons en utilisant l’interférence bayésienne. L’état de l’art des algorithmes concernant la déconvolution et déconvolution aveugle est exposé dans le cadre d’un travail bayésien. Dans la première partie, nous constatons que la diffraction limitée de l’objectif et le bruit intrinsèque, sont les distorsions primordiales qui affectent les images d’un spécimen fin. Une approche de minimalisation alternative (AM), restaure les fréquences manquantes au-delà de la limite de diffraction, en utilisant une régularisation de la variation totale sur l’objet, et une contrainte spatiale sur la PSF. En outre, des méthodes sont proposées pour assurer la positivité des intensités estimées, conserver le flux de l’objet, et bien manier le paramètre de la régularisation. Quand il s’agit d’imager des spécimens épais, la phase de la fonction de la pupille, due à l’aberration sphérique (SA) ne peut être ignorée. Dans la seconde partie, il est montré qu’elle dépend de la discordance de l’index de réfraction entre l’objet et le milieu d’immersion de l’objectif et de la profondeur sur la lamelle. Les paramètres d’imagerie et la distribution de l’intensité originelle de l’objet sont récupérés en modifiant les algorithmes AM. Due à l’incohérence de la microscopie à fluorescence, la phase de récupération des intensités observées est possible en contraignant la phase par l’utilisation d’optiques géométriques. Cette méthode pourrait être étendue pour restituer des spécimens affectés par la SA. Comme la PSF varie dans l’espace, un modèle de quasi-convolution est proposé, et la PSF est rendue approximative. Ainsi, en plus de l’objet, il suffit d’estimer un seul libre paramètre
Confocal laser scanning microscopy is a powerful technique for studying biological specimens in three dimensions (3D) by optical sectioning. Although ubiquitous, there are uncertainties in the observation process. As the system’s impulse response or point-spread function (PSF) is dependent on both the specimen and imaging conditions, it should be estimated from the observed images along with the object. This problem is ill-posed, under-determined, and as the measurement process is quasi-random in nature, we treat the problem by using Bayesian inference. The state of the art déconvolution and blind déconvolution algorithms are reviewed within a Bayesian framework. In the first part, we recognize that the diffraction-limited nature of the objective lens and the intrinsic noise are the primary distortions that affect this specimen images. An alternative minimization (AM) approach restores the lost frequencies beyond the diffraction limit by using a total variation regularization on the objet, and a spatial constraint on the PSF. Additionally, some methods are proposed to ensure positivity of estimated intensities, conserve the object’s flux, and to handle the regularization parameter. When imaging thick specimens, the phase of the pupil function due to spherical aberration (SA) cannot be ignored; It is shown to be dependent on the refractive index mismatch between the object and the objective immersion medium, and the depth under the cover slip. The imaging parameters and the object’s original intensity distribution is recovered by modifying the AM algorithm. Due to the incoherent nature of fluorescence microscopy, phase retrieval from the observed intensities is possible by constraining the phase using geometrical optics. This method could be extended to restore specimens affected by SA. As the PSF is space varying, a quasi-convolution model is proposed, and the PSF approximated so that, apart from the object, there is only one free parameter to be estimated

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Hanna, Gabriel Joseph. "Confocal microscopy of fluid argon under pressure". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Dissertations/Fall2009/g_hanna_121109.pdf.

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Pereira-Cenci, Tatiana. "Avaliação da formação de biofilme de especies de candida sobre a superficie de resinas acrilicas para base e reembasamento de proteses removiveis". [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288146.

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Orientador: Altair Antoninha Del Bel Cury
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A candidose é a infecção oral fúngica mais comum diagnosticada em humanos, com prevalência de até 77,5% em usuários de próteses removíveis. Embora tenha sido inicialmente associada apenas à Candida albicans, outras espécies de Candida podem ser responsáveis por mais de 50% dos casos de infecção. Ainda, fatores como presença de saliva, bactérias e características de materiais utilizados para confecção de próteses removíveis parecem desempenhar importante papel na adesão, colonização e formação de biofilme por Candida. Assim, este trabalho objetivou (i) discutir os fatores que controlam a adesão inicial, colonização e formação de biofilme de Candida em um artigo de revisão, no intuito de apontar diretrizes para estudos futuros e ainda, mostrar de que forma estes fatores podem ser controlados, ajudando na prevenção da doença; (ii) verificar a influência in vitro de alguns dos fatores supracitados na formação de biofilme de C. albicans sobre a superfície de hidroxiapatita, resina acrílica e reembasador temporário e; (iii) avaliar in situ a formação de biofilme sobre espécimes de resina acrílica e reembasadores de próteses inseridos nas próteses totais de 21 voluntários. Para avaliação da formação de biofilme de C. OBS.: O resumo na integra poderá ser visualizado no link ou texto completo da tese digital.
Abstract: Candida-associated stomatitis is the most common fungal oral infection in humans, with a prevalence reported in up to 77.5% of a population wearing dentures. Disease-associated Candida species have shifted from C. albicans to non-albicans species, these latter being responsible for more than 50% of the infections. Additionally, several factors as the presence of saliva, bacteria and dental prostheses materials¿ characteristics seem to be related to the adhesion, colonization and biofilm formation of Candida. This study aimed (i) to discuss the factors that govern initial adherence, colonization and biofilm formation of Candida by means of a review article, in order to suggest future research and show how these factors may be controlled, therefore helping to prevent the disease; (ii) to verify the influence of several of these factors in the biofilm formation of C. albicans in vitro, on hydroxyapatite, acrylic resin and soft denture liner; (iii) to evaluate in situ biofilm formed on acrylic resin and denture liner specimens inserted in the lower dentures of 21 volunteers. For C. Note: the complete abstract is avaiable with the link or full eletronic digital theses or dissertations.
Doutorado
Protese Dental
Doutor em Clínica Odontológica

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Eigenbrot, Ilya Vladimirovich. "A time-resolved confocal fluorescence microscope". Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342331.

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Beckham, Richard Edward. "Confocal microscopy study of colloidal sedimentation and crystallization". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2682.

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Lashin, Nabil Aly Mohamed Aly. "Restoration methods for biomedical images in confocal microscopy". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975678167.

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19

Zator, Maria Malgorzata. "Membrane fouling characterization by confocal scanning laser microscopy". Doctoral thesis, Universitat Rovira i Virgili, 2009. http://hdl.handle.net/10803/8580.

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En sectores tan diversos como la industria alimentaria, la biotecnología y el tratamiento de aguas residuales, la filtración tangencial con membranas se viene utilizando de forma creciente en la separación, purificación y clarificación de distintas corrientes de proceso que contienen gran variedad de compuestos orgánicos. La limitación principal para el empleo industrial de las técnicas de separación por membranas es el ensuciamiento de éstas. El ensuciamiento se atribuye, de forma general, a la reducción en el diámetro de los poros, a su bloqueo y/o a la formación de un depósito en la superficie de la membrana. El avance en el desarrollo de técnicas para la caracterización, el control y la prevención del ensuciamiento de las membranas ha estado limitado por la falta de técnicas adecuadas y no invasivas para la medición del ensuciamiento. El objetivo principal del presente proyecto es desarrollar estrategias apropiadas para aplicar microscopía láser confocal de barrido (CSLM) al estudio del ensuciamiento de membranas de filtración, centrándose en el ensuciamiento causado por macromoléculas biológicas. En la tesis se han llevado a cabo experimentos de microfiltración (MF) de soluciones modelo puras y de mezclas de proteínas, polisacáridos y polifenoles. Las imágenes captadas mediante CSLM de las membranas al final de diferentes experimentos de filtración, han servido para obtener información cualitativa, sobre localización de las distintas moléculas, y cuantitativa, sobre la presencia individual de cada compuesto en el interior y la superficie de la membrana. Se han realizado también intentos de aplicación de visualización en línea mediante CSLM del proceso de microfiltración.
In fields such as the food and dairy industries, biotechnology, and the treatment of industrial effluents, pressure-driven membrane processes such as microfiltration are increasingly being used for the separation, purification and clarification of protein-containing solutions. A major limitation to the widespread use of membrane filtration, however, is fouling. Fouling is usually attributed to pore constriction, pore blocking or the deposition of cells and cell debris on the membrane surface and can lead to a reduction in the filtrate flux of more than an order of magnitude. Progress in developing a means for characterizing, controlling and preventing membrane fouling has been impeded by lack of suitable non-invasive fouling-measurement techniques. The main aim of this study is to develop suitable strategies for applying Confocal Scanning Laser Microscopy (CSLM) to characterise membrane fouling caused by biological macromolecules. Microfiltration experiments of single, binary and ternary model solutions of proteins, polysaccharides and polyphenols were carried out and CSLM images of the membranes at the end of the different filtration runs were obtained, in order to obtain quantitative and qualitative information about fouling patterns. Some trials of on-line monitoring of cross-flow microfiltration processes were also carried out.

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20

Liu, Yanyan. "Colloidal particles for confocal microscopy and optical tweezing". Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:c23db801-bbfa-42eb-9672-38236a3ffdfd.

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A novel colloidal model system is developed for the purpose of achieving simultaneous three-dimensional (3D) confocal imaging and optical tweezing of impurity probe particles embedded in a dense material of colloidal host particles. First, the colloidal host particles are developed from 3-trimethoxysilyl-propylmethacrylate (TPM), and the solvent mixture is tuned to match the refractive index and the density of the particles. A sedimentation-diffusion equilibrium profile of the TPM particles was imaged in 3D to establish suitability of the system for 3D confocal laser scanning microscopy, and to study its phase behaviour and particle dynamics. Then, core-shell particles, which consist of a high refractive index core and a TPM shell, are synthesised to be used as the impurities. The versatility of the two-step coating procedure with TPM has been demonstrated on several core materials, and the optical properties of the core-shell particle are established using digital holographic microscopy and their optical trapping strengths. Together with the TPM host particles, the core-shell particles are shown to be suitable impurity probes in dense colloidal materials, as they can be manipulated using optical tweezers in all three-dimensions, whilst the structure and dynamics of the surrounding host particles can be imaged simultaneously using fast confocal laser scanning microscopy. Subsequently, to demonstrate the capability of the TPM-based colloidal model system, the depletion potential of a pair of core-shell probe particles embedded in a sea of TPM host particles has been measured using optical tweezing. This is derived from comparing the direct pair potential between the core-shell particles in a TPM refractive index matching solvent, and the potential of mean force for the core-shell particles embedded in a dense fluid region of the TPM host particles. Direct visualisation of the liquid structures of the TPM host particles in the binary system around the probe particles has been linked to the form of the depletion potential, and its oscillatory nature as a function of the particle separation. Lastly, the formation of colloidal dumbbell particles is discussed. The dumbbell formation has been rationalised in terms of the total surface energy of droplet formation on spherical surfaces and the calculations are compared with experimental results from coating various seed particles with TPM. Using optically anisotropic dumbbell particles and tuning the refractive index of the dispersion medium, a preliminary two-trap experiment has been conducted which shows unusual trapping behaviour when a time-delayed feedback trapping trajectory has been applied.

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21

Boruah, Bosanta Ranjan. "Programmable diffractive optics for laser scanning confocal microscopy". Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/11911.

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22

Aziz, David Joshua. "Confocal microscopy through a fiber-optic imaging bundle". Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187269.

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This dissertation describes the implementation of confocal microscopy through a fiber-optic imaging bundle. This system, the fiber-optic imaging-bundle confocal microscope, permits the optical-sectioning effect of confocal microscopy to be applied to a range of samples inaccessible to a conventional confocal microscope. Two such systems were designed and built. The first system is a modified laboratory microscope used to demonstrate and evaluate the performance of the fiber-optic imaging-bundle confocal microscope. The second system is a real-time slit-scanning microscope that is expected to be a suitable design for in-vivo medical applications. Fiber-optic imaging bundles are discussed in some detail. A number of parameters of three flexible silica imaging bundles were measured and the suitability of these bundles for use in the microscope is evaluated. A new reflection technique for measurement of optical-fiber refractive indices was developed and applied to the evaluation of these imaging bundles.

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23

Gareau, Daniel S. "In vivo confocal microsopy in turbid media : a thesis /". Restricted access until December 2007 at:, 2006. http://content.ohsu.edu/u?/etd,161.

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24

Thomaz, André Alexandre de 1980. "Ferramenta biofotônica integrada para manipulações e microscopias confocais". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277547.

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Orientador: Carlos Lenz Cesar
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
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Resumo: A pesquisa em fotônica biomedica está claramente tomando a direção do entendimento de processos biológicos a nível celular. A resolução necessária para atingir esse objetivo requer praticamente ferramentas fotônicas. Contudo, uma integração de diferentes ferramentes fotônicas e uma aproximação funcional serão necessárias para acessar os processos biomecânicos e bioquímicos celulares. Deste modo nós podemos observar eventos bioquímicos disparados mecanicamente ou eventos mecânicos disparados bioquimicamente, ou até mesmo observar simultâneamente eventos biomecânicos e bioquímicos disparados por outros meios, entre outros, eletricamente. Uma das grandes vantagens das ferramentas fotônicas é a sua facilidade de integração. Nós desenvolvemos uma ferramenta integrada incorporando pinça óptica simples com Microscopia Confocal "Single-photon" e Multifóton. O sistema consegue realizar microscopias de fluorescência excitada pela absorção de dois fótons e geração de segundo harmônico em conjunto com manipulações ópticas. Medidas de força, elasticidade e viscosidade de membranes esticadas podem ser monitoradas em tempo real pelas microscopias confocais, bem como protozoários capturados opticamente, como, por exemplo, Trypanosoma cruzi. Nós mostraremos vários exemplos do uso de tal ferramenta integrada e seu potencial para observar processos mecânicos e bioquímicos a nível celular
Abstract: The research in biomedical photonics is clearly evolving in the direction of the understanding of biological processes at the cell level. The spatial resolution to accomplish this task practically requires photonics tools. However, an integration of different photonic tools and a multimodal and functional approach will be necessary to access the mechanical and biochemical cell processes. This way we can observe mechanicaly triggered biochemical events or biochemicaly triggered mechanical events, or even observe simultaneously mechanical and biochemical events triggered by other means, e.g. electricaly. One great advantage of the photonic tools is its easiness for integration. Therefore, we developed such integrated tool by incorporating single Optical Tweezers with Confocal Single and Multiphoton Microscopies. This system can perform 2-photon excited fluorescence and Second Harmonic Generation microscopies together with optical manipulations. Force, elasticity and viscosity measurements of stretched membranes can be followed by real time confocal microscopies. Also opticaly trapped living protozoas, such as Trypanosoma cruzi. Integration with CARS microscopy is under way. We will show several examples of the use of such integrated instrument and its potential to observe mechanical and biochemical processes at cell level
Mestrado
Física
Mestre em Física

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25

Tefft, John. "The Study of Coating and Ink Penetration into Coating Structures Using a Confocal Laser Scanning Microscope". Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/TefftJ2007.pdf.

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26

Yildiz, Bilge Can. "Imaging Of Metal Surfaces Using Confocal Laser Scanning Microscopy". Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613641/index.pdf.

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Optical imaging techniques have improved much over the last fifty years since the invention of the laser. With a high brightness source many imaging applications which were once inaccessible to researchers have now become a reality. Among these techniques, the most beneficial one is the use of lasers for both wide-field and confocal imaging systems. The aim of this study was to design a laser imaging system based on the concept of laser scanning confocal microscopy. Specifically the optical system was based on optical fibers allowing the user to image remote areas such as the inner surface of rifled gun barrels and/or pipes with a high degree of precision (+/- 0.01 mm). In order to build such a system, initially the theoretical foundation for a confocal as well as a wide-field imaging system was analyzed. Using this basis a free-space optical confocal system was built and analyzed. The measurements support the fact that both the objective numerical aperture and pinhole size play an important role in the radial and axial resolution of the system as well as the quality of the images obtained. To begin construction of a confocal, optical-fiber based imaging system first an all fiber wide-field imaging system was designed and tested at a working wavelength of 1550 nm. Then an all fiber confocal system was designed at a working wavelength of 808 nm. In both cases results showed that while lateral resolution was adequate, axial resolution suffered since it was found that the design of the optical system needs to take into account under-filling of the objective lens, a result common with the use of laser beams whose divergence is not at all like that of a point source. The work done here will aid technology that will be used in the elimination process of faulty rifling fabrication in defense industry. The reason why the confocal technique is preferred to the conventional wide-field one is the need for better resolution in all directions. Theoretical concepts and mathematical background are discussed as well as the experimental results and the practical advantages of such a system.

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27

Luedtke, Michael A. Papazoglou Elisabeth S. "Wavelength effects on in vivo confocal scanning laser microscopy/". Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/2518.

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28

Jiang, Shihong. "Non-scanning fluorescence confocal microscopy using laser speckle illumination". Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10139/.

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Confocal scanning microscopy (CSM) is a much used and advantageous form of microscopy. Although CSM is superior to conventional microscopy in many respects, a major disadvantage is the complexity of the scanning process and the sometimes long time to perform the scan. In this thesis a novel non-scanning fluorescence confocal microscopy is investigated. The method uses a random time-varying speckle pattern to illuminate the specimen, recording a large number of independent full-field frames without the need for a scanning system. The recorded frames are then processed in a suitable way to give a confocal image. The goal of this research project is to confirm the effectiveness and practicality of speckle-illumination microscopy and to develop this proposal into a functioning microscope system. The issues to be addressed include modelling of the system performance, setting up experiments, computer control and image processing. This work makes the following contributions to knowledge: * The development of criteria for system performance evaluation * The development of methods for speckle processing, whereby the number of frames required for an image of acceptable quality can be reduced * The implementation of non-scanning fluorescence confocal microscopy based upon separate recording of the speckle patterns and the fluorescence frames, demonstrating the practicality and effectiveness of this method * The realisation of real-time image processing by optically addressed spatial light modulator, showing how this new form of optical arrangement may be used in practice The thesis is organised into three main segments. Chapters 1-2 review related work and introduce the concepts of fluorescence confocal microscopy. Chapters 3-5 discuss system modelling and present results of performance evaluation. Chapters 6-8 present experimental results based upon the separate recording scheme and the spatial light modulation scheme, draw conclusions and offer some speculative suggestions for future research.

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29

SANTOS, Rodrigo Galvão dos. "Second-harmonic confocal microscopy of single ß-BBO nanocrystals". Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/26623.

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SANTOS, Rodrigo Galvão dos, também é conhecido em citações bibliográficas por: GALVÃO, Rodrigo dos Santos
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CNPq
In this M. Sc. thesis, we apply the Confocal Microscopy (CM) technique for optical characterization of single β–barium-borate (BBO) nanocrystals (NCs). CM can produce images by reflection and fluorescence with high signal-to-noise ratio. Our experimental setup allows the measurement of the SH polarization response to be recorded and the results can be used to determine the NCs orientation as well as to obtain information about the NL susceptibility tensor, allowing a detailed characterization of the sample. Home-synthesized BBO NCs were previously characterized by several techniques such as X-ray diffraction (XRD), High-Resolution Transmission Electronic Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and Diffuse Reflectance (DR), assuring that non-centrosymmetric and single crystalline phase have been synthesized. The NCs have average dimensions of 150 nm×15 nm×15 nm, and these needles are oriented in the direction of the crystallographic c-axis. On the other hand, the HRTEM and SAED showed the presence of defects in the needles composed of crystallites about 10 nm in size that are formed during the growth by the rotation of crystallographic planes around the c-axis. Due to symmetry properties of BBO, the technique employed in this work cannot discern rotations along the c-axis and thus, the defects are effectively irrelevant to SH CM as well to polarization dependent measurements. The experimental setup uses a mode-locked Ti:Sapphire laser (120 fs, 76 MHz, 820 nm) as a light source for a home-made inverted optical confocal microscope employing a 100X NA=1.25 objective, set under a piezo module for scanning the sample in relation to the laser focal region. A dichroic mirror serves as a beam splitter, ensuring the incidence of the laser on the sample and the transmission of the SH signal. The confocal aspect is obtained by using a 10 μm pinhole in the detection path. Spectral information is obtained with a monochromator equipped with a photomultiplier. A half-wave plate placed right before the dichroic mirror allows measurements of the SH signal as a function of the laser polarization orientation. Several images of single NCs were made by raster scanning of the sample in 2 and 3 dimensions, showing a good agreement with the corresponding imaging theory. The polarization dependence of the SH signal allowed the identification of individual particles from aggregates and the data was fitted using a model that takes into account the BBO symmetries and the optical elements in the setup. The model considers: i) the electrostatic approximation; ii) the effects of the microscope’s objective used to focus the light on the sample in epi-geometry configuration and iii) the properties of χ⁽²⁾ for the β–BBO NCs. The results constitute a proof of concept for high resolution CM of single NL emitters as well an optical characterization for BBO NCs not hitherto described in the literature.
Nesta dissertação de mestrado, nos aplicamos a técnica de Microscopia Confocal (MC) para caracterização óptica de nanocristais (NCs) individuais de Beta-Borato de bário (BBO). A MC e capaz de produzir imagens por reflexão e fluorescência com elevada relação sinal-ruído. Nosso aparato experimental permite que a medida da resposta de polarização seja registrada e que os resultados sejam usados para determinar a orientação dos NCs bem como obter informações sobre o tensor de susceptibilidade NL, permitindo uma caracterização detalhada da amostra. NCs de BBO de síntese própria foram previamente caracterizados por diversas técnicas como difração de raio-X (DRX), microscopia eletrônica de transmissão de alta resolução (METAR), difração de elétrons de área selecionada (DEAS) e refletância difusa (RD), garantindo que foi obtida uma fase cristalina unica e nao centrossimétrica. Os NCs tem um tamanho médio de 150 nm×15 nm×15 nm e essas agulhas são orientadas na direção do eixo cristalográfico c. Por outro lado, a METAR e a DEAS mostraram a presença de defeitos nas agulhas compostos por cristalitos de cerca de 10 nm de diâmetro que são formados durante o crescimento pela rotação dos planos cristalográficos em torno do eixo c. Devido a propriedades simétricas do BBO, a técnica empregada neste trabalho não é capaz de distinguir tais rotações, logo, os defeitos são efetivamente invisíveis a MC assim como as medidas de polarização. O arranjo experimental usa um laser de Ti:Sa (120 fs, 76 MHz, 820 nm) como a fonte luminosa para um microscópio confocal invertido manufaturado, que emprega uma objetiva posicionada num modulo piezo para varredura da amostra com relação a posição focal do laser. Um espelho dicroico atua como um divisor de feixe, garantindo a incidência do laser na amostra e a transmissão do sinal de SH. O aspecto confocal e obtido usando um pinhole de 10 μm no caminho de deteccao. Informacao espectral e obtida com um monocromador equipado com uma fotomultiplicadora. Uma placa de meia onda colocada antes do espelho dicroico permite medidas do sinal de SH como função da orientação de polarização do laser. Diversas imagens de NCs individuais foram feitas por raster scan da amostra em 2 e 3 dimensões, mostrando uma boa concordância com a teoria de formação de imagens correspondente. A dependência de polarização do sinal de SH permitiu a distinção entre partículas individuais e agregados e os dados foram ajustados com um modelo que leva em consideração as simetrias do BBO e os elementos ópticos do setup. O modelo considera: i) a aproximação eletrostática; ii) os efeitos da objetiva de microscópio usada para focalizar a luz na amostra em configuração de reflexão e iii) as propriedades de χ⁽²⁾ para os NCs de β–BBO. Os resultados constituem uma prova de conceito para MC de alta resolução de emissores individuais NL bem como uma caracterização óptica de NCs de BBO ate então não descrita na literatura.

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Silva, Wander José da 1980. "Influencia da superficie de resinas de poli (metil metacrilato) na estrutura de biofilmes de Candida albicans". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289058.

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Orientadores: Altair Antoninha Del Bel Cury, Renata Cunha Matheus Rodrigues Garcia
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Os biofilmes de Cândida albicans formados sobre a superfície de resina de poli (metil metacrilato) (PMMA) apresentam alta virulência em função da liberação de enzimas hidrolíticas e são responsáveis pela candidose oral, infecção fúngica mais comum em usuários de próteses dentais removíveis. A organização do biofilme em várias camadas celulares envoltos por matriz de polissacarídeos extracelulares leva estas camadas celulares a estado metabólicos diferenciados e, portanto o uso da técnica de redução XTT ( 2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide), cuja reação é dependente da atividade celular, pode ser questionada. Assim, objetivou-se no primeiro estudo que compõem este trabalho, padronizar e aperfeiçoar esta técnica através da suplementação de glicose. Para isso, biofilmes de Cândida albicans ATCC 90028 com tempos de crescimento de 24, 48 e 72 h foram avaliados. Para estabelecer o melhor tempo de incubação do XTT, este foi mantido a temperatura de 37 °C, em tempos de 90, 180 e 270 minutos. A fórmula padrão do teste XTT (controle) foi modificada com a adição de 50, 100 e 200 mM de glicose para os grupos experimentais. Os melhores resultados para a incubação foram observados com tempo de 180 minutos e para a suplementação de glicose à concentração de 200 mM (p<0,001). Uma vez determinada a melhor condição de leitura da bioatividade dos biofilmes, foi idealizado o segundo estudo, que objetivou a mensuraçâo da bioatividade e a análise morfológica de biofilmes de Cândida albicans desenvolvidos sobre a superfície de PMMA. Duas resinas a base de PMMA (banho de água e microondas) foram utilizadas como substrato para o desenvolvimento de biofilmes de duas cepas de Cândida albicans (ATCC 90028 e SC5314). A atividade metabólica destes biofilmes foi mensurada com a técnica modificada de redução mitocondrial do XTT. A análise da morfologia da fase de adesão e dos biofilmes de 24, 48 e 72 horas foi avaliada com o auxilio do microscópio de varredura confocal a laser e o microscópio eletrônico de transmissão A combinação das análises da morfologia com a mensuraçâo da bioatividade, permitiu verificar o desenvolvimento do biofilme, desde a fase de adesão, com alta atividade metabólica, evoluindo para a constituição de uma comunidade microbiana de alta complexidade estrutural com a presença de matriz de polissacarídeos extracelulares, através da qual os nutrientes se difundem, porém dotados de pouca atividade metabólica. O método de ativação das resinas não interferiu na bioatividade do biofílme e com a morfologia do biofllme formado para a cepa de Candida albicans SC 5314. Com base nestes estudos concluiu-se que a incubação de 180 minutos utilizando a suplementação de 200 mM de glicose apresenta resultados de atividade metabólica celular com a menor variação para o estudo de biofilmes de Candida albicans e que a morfologia do biofílme de ambas as espécies foi fator fundamental para as diferenças na estrutura do biofílme
Abstract: Candida albicans biofilms, developed on poly (methyl methacrylate) (PMMA) resin surfaces show high virulence index due to hydrolytic enzyme secretion and are responsible for oral candidosis in removable denture wearer. Since biofilms are surrounded by an extracellular polysaccharides matrix, the nutrients diffusion across the cell layers is difficulted, occasioning cell with different metabolic states. Thus, considering that the XTT reduction assay is dependent of cellular activity, its use for evaluating mature biofilms may lead to inaccuracies since biofilm bottom cells layers tends to be relatively quiescent at later stages of biofilm formation. The aim of the first study was the improvement of the XTT reduction assay by using glucose supplements in the standard XTT formulation. Candida albicans ATCC 90028 was used to form 24, 48 and 72 hours biofilm. The oxidative activity at 90, 180 and 270 minutes of incubation was evaluated. The standard XTT composition was modified by the addition of 50, 100 and 200 mM of glucose. The control comprised XTT formulation without glucose supplements. Biofilm growth yield after 180 min incubation, when evaluated with the 200 mM glucose supplemented XTT produced the most consistent readings on repetitive testing (pO.001), After the results of the determination of the oxidative activity assay using XTT supplemented by 200 mM glucose second study was conducted in which it was evaluated the characteristics of biofilm development of Candida albicans on two different poly (methyl methacrilate) resins (PMMA). Thus, two different Candida albicans strain (ATCC 90028 and SC5314) were allowed to develop its biofilm in two PMMA surfaces with different polymerization method: waterbath (WB) and microwave (MW). Different time points (adhesion, 24, 48 and 72 hours) were compared. Surface roughness (SR) and surface free energy (SFE) of PMMA specimens were previously measured. Oxidative activity was measured by XTT. Confocal images were used to measure bio-volume, thickness, biofilm roughness, diffusion and the of live/dead cells proportion in the different biofilm development stages. Cell counts were used to estimate the number of cells, and a combination of these techniques allowed to describe the Candida albicans biofilms development, starting from a small amount of cells with high oxidative activity, reaching to microbial community of complexity structural prosperities, with the presence of a matrix of polysaccharide, however with low oxidative activity. WB and MW showed no difference regards SR. and SFE means (p>0,05) and oxidative activity showed different results for each specie (p<0.001). Based on both studies, it can be conclude that 180 min incubation with the 200 mM glucose supplemented XTT generates more accuracy in oxidative activity results and also that the different polymerization method of PMMA are not able to interfere with biofilm development and main differences detected were related to the intrinsic characteristic of each Candida strain and biofilm development time
Doutorado
Protese Dental
Doutor em Clínica Odontológica

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31

Oliveira, Marcelo Tavares de. "Avaliação dos efeitos da irradiação do substrato dentinario com laser Er : YAG nos procedimentos restauradores adesivos : analise da permeabilidade, das propriedades fisicas e observação microscopica". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287814.

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Orientador: Marcelo Giannini
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O uso de técnicas alternativas para preparo cavitário vem ganhando grande importância na Odontologia moderna. Entre estas tecnologias, o laser tem sido alvo de inúmeros estudos e para a realização de preparos cavitários o laser de Er:YAG é um dos mais indicados. Os objetivos deste estudo foram avaliar os efeitos de diferentes parâmetros de irradiação do substrato dentinário com laser de Er:YAG nos procedimentos restauradores adesivos e suas conseqüências sobre o substrato e sobre a união resina-dentina. Os testes foram realizados em superfícies dentinárias planificadas de terceiros molares humanos hígidos unidos a três diferentes sistemas adesivos (Single Bond 2 - 3M ESPE, Clearfil Protect Bond - Kuraray Medical Inc. e Clearfil Tri-S Bond - Kuraray Medical Inc.). Estas avaliações compreenderam o estudo da permeabilidade dentinária, da resistência de união, da longevidade e qualidade da união, além da análise da ultra-estrutura da interface de união através de microscopia eletrônica de transmissão e microscopia de varredura confocal laser. Os dados de permeabilidade e resistência de união foram analisados e submetidos à análise estatística com ANOVA 1-critério e ANOVA 3-critérios, respectivamente; ao encontrar diferenças significativas, o teste de Tukey foi utilizado. O nível de significância foi fixado em 5%. Os resultados mostraram ocorrer uma redução significativa na permeabilidade dentinária e que o parâmetro de 120mJ/4Hz foi o que promoveu a maior redução. Quanto à resistência de união, este estudo demonstrou que inicialmente, a irradiação com laser de Er:YAG reduz os valores de resistência de união, no entanto após 6 meses os valores são semelhantes tanto para o grupo controle, quanto para os grupos que foram irradiados. Além disso, pôde ser observado, que os sistemas autocondicionantes foram menos susceptíveis aos efeitos da irradiação do substrato, apresentando um comportamento mais uniforme. O sistema autocondicionante de dois passos também se mostrou mais estável ao longo do tempo. As imagens em microscopia eletrônica de transmissão e microscopia de varredura confocal laser, mostraram a formação de camada híbrida para todos os adesivos estudados com diferentes espessuras, quando aplicados sobre a dentina abrasionada. Não foi possível identificar camada híbrida uniforme e bem definida quando os sistemas foram aplicados em dentina irradiada com laser de Er:YAG, independentemente do parâmetro utilizado. Diante disso, os resultados sugerem que a irradiação da dentina com laser de Er:YAG reduz a permeabilidade dentinária, podendo influenciar na união dos adesivos à dentina nos períodos iniciais, entretanto após 6 meses os grupos irradiados foram iguais ao grupo controle. O exame ao microscópio revelou que a formação da camada híbrida é irregular e não-uniforme quando a dentina foi irradiada.
Abstract: The use of alternative techniques for cavity preparation is more common nowadays. Among these technologies, laser is the target of a great number of studies. The objectives of this study were to evaluate the effects of different parameters of dentin irradiation with Er:YAG laser on the adhesive procedures and their consequences over the substrate and resin dentin interface. Procedures were performed over flat dentin surfaces of human third molars bonded to three different adhesive systems ((Single Bond 2 - 3M ESPE, Clearfil Protect Bond - Kuraray Medical Inc. e Clearfil Tri-S Bond - Kuraray Medical Inc.). The evaluation tests were: dentin permeability, microtensile bond strengths, durability and the analysis of the ultra-structure using transmission electron microscope (TEM) and confocal laser scanning microscope (CSLM). Dentin permeability data and microtensile bond strength data were analyzed with one-way ANOVA and three-way ANOVA, respectively. Tukey test was used to point out differences among the tested groups. The significance level was fixed at 5%. Results showed a significative reduction on the dentin permeability and the 120mJ/4Hz parameter promoted the greatest reduction. For the microtensile bond strength test, this study showed that the irradiation with Er:YAG laser reduce the bond strength values at the baseline. After six months all groups became similar. Furthermore, self-etching systems were less affected by the Er:YAG laser irradiation. The two-step self-etching system seemed the more stable over time. TEM and CLSM images showed the hybrid-layer formation for all adhesive tested. The hybrid-layers had different thicknesses when the adhesive systems were bonded to abraded dentin. The observation of a uniform and well defined hybrid-layer was not possible when the adhesive systems were bonded to laser irradiated dentin, regardless of the used parameter. According to the data presented, dentin irradiation with Er:YAG laser reduce the permeability of the substrate, interfering on the bonding strength to dentin at the baseline, however, after six months laser irradiated groups were similar to control groups. Microscope analysis revealed that hybrid layer formation was irregular and non-uniform when dentin was laser irradiated.
Doutorado
Doutor em Materiais Dentários

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Gomes, Maria Clara Ferreira de Almeida Cardia. "Photoactive nanoparticles for oprical bio imaging". Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22483.

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Doutoramento em Nanociências e Nanotecnologia
O objetivo principal desta dissertação foi o desenho, síntese e funcionalização de novos agentes para bio imagem baseados em nanopartículas. Devido à sua biocompatibilidade e facilidade de funcionalização da superfície, as nanopartículas têm sido amplamente utilizadas em aplicações biológicas. Aqui, apresentamos a aplicação de dois conjuntos de nanopartículas, nanopartículas de sílica (Si) e ouro (Au) como agentes de bio imagem em microscopia confocal de fluorescência e de raman, respetivamente. Nanopartículas fluorescentes do tipo “core-shell” foram preparadas através da metodologia de microemulsão inversa (intervalo de tamanhos 20 – 40 nm), com compostos à base de lantanídeos (Ln) (Ln = Europio III (EuIII) e Terbio III (TbIII) no interior (core) e Si como camada protetora. A funcionalização superficial das nanopartículas de Si foi conseguida através da química de silanos. Os Ln foram coordenados com compostos orgânicos como o ácido picolínico (picOH) ou com polioxometalatos (POM). A coordenação com o picOH trouxe ligeiras modificações no perfil fluorescente do metal, permitindo aos complexos Ln/picOH a sua excitação a comprimentos de onda de energia mais baixos. Este fenómeno é atribuído ao efeito de antena causado pelo ligando. Foram também realizados dois tipos diferentes de funcionalização, visando um especifico alvo. Cargas positivas foram usadas para direcionar para microorganismos (Candida albicans) e hidratos de carbono para células cancerígenas. As nanopartículas de Si fluorescentes com cargas positivas foram internalizadas pela C. albicans a sua distribuição visualizada através d e microscopia confocal de fluorescência. Foi possível observar a distribuição dessas nanopartículas no citoplasma celular sem internalização no núcleo. Em analogia, moléculas de hidrato de carbono (glucose e galactose) foram agrafadas à superfície de nanopartículas de Au de diferentes tamanhos (15, 30, 40 e 60 nm) e estudadas como possíveis nanomarcadores usando microscopia confocal de Raman como técnica ótica. Numa primeira abordagem, foram realizados estudos preliminares sobre a capacidade destas nanopartículas para produzir aumento da dispersão de superfície (SERS) bem como a sua biocompatibilidade nas células 9Lluc de glioma de rato. Os resultados mostraram os alongamentos característicos dos hidratos de carbono, para todas as nanopartículas de Au funcionalizadas como sinais SERS e, nenhuma citotoxicidade celular. Observou-se uma preferência para as nanopartículas de Au com 40 e 60 nm funcionalizadas com galactose. Além disso, a microscopia eletrónica de transmissão mostrou distribuição das nanopartículas em todo o citoplasma, mais especificamente dentro de organelos vesiculares, sem acumulação no núcleo. As nanopartículas de Au 60 nm funcionalizadas com galactose e glucose foram então estudadas em células cancerígenas, em tecidos tumorais e tumores sólidos como nanomarcadores, através da microscopia confocal de Raman. Estas nanoparticulas mostraram-se adequadas para serem usadas como nanomarcadores, conseguindo superar a autofluorescência proveniente dos tecidos biológicos. Além disso, um estudo de profundidade mostrou que seu sinal de SERS pode ser coletado em tumores sólidos até 2 mm de profundidade. Esta dissertação mostrou que nanopartículas podem ser utilizadas como marcadores alternativos aos fluoróforos comuns utilizados hoje em dia, apresentando biocompatibilidade e especificidade. Em relação às técnicas óticas utilizadas, a microscopia confocal de Raman mostrou ser uma alternativa vantajosa às mais comuns
The main goal of this dissertation was the design, synthesis and functionalization of new nanoparticles-based bio imaging agents. Due to their biocompatibility and ease surface functionalization, nanoparticles have been widely used in biological applications. Herein, we present the application of two sets of nanoparticles, silica (Si) and gold (Au) nanoparticles as bio imaging agents in confocal fluorescent and raman microscopy, respectively. Fluorescent core-shell Si nanoparticles were prepared through the reverse microemulsion methodology (size range 20 – 40 nm), with lanthanide (Ln)- based compounds [Ln = Europium III (EuIII) and Terbium III (TbIII)]) in the core and Si as protective shells. The surface functionalization of Si nanoparticles was achieved through silane chemistry. Ln were coordinated with organic compounds such as picolinic acid (picOH) or with polyoxometalates (POM). The coordination with the picOH brought slight modifications in the fluorescent profile of the metal ion, allowing for the Ln/picOH complexes their excitation at lower energy wavelengths. This phenomenon is attributed to the antenna effect caused by the ligand. Two different types of functionalization were also performed, aiming specific targeting. Positive charges were used to target microorganisms (Candida albicans) and carbohydrates to target cancer cells. Positive charged fluorescent Si nanoparticles were internalized by C. albicans and their distribution visualized through confocal fluorescent microscopy. It was possible to note the distribution of these nanoparticles at the cellular cytoplasm with no internalization in the nucleus. In analogy, carbohydrate moieties (glucose and galactose) were stapled in the surface of different sized Au nanoparticles (15, 30, 40 and 60 nm) and studied as possible nanoprobes using confocal Raman microscopy as optical technique. In a first approach, preliminary studies regarding to the ability of these nanoparticles produce surface enhanced resonance scattering (SERS) as well as their biocompatibility in rat 9Lluc glioma cells was studied. Results showed the characteristic carbohydrate stretches for the all the functionalized Au nanoparticles in solution as SERS signals, and no cellular cytotoxicity. Preference for the 40 and 60 nm Au nanoparticles functionalized with galactose was observed. Moreover, the transmission electron microscopy showed distribution by the nanoparticles throughout the cytoplasm more specifically within vesicular organelles, with no accumulation in the nucleus. The 60 nm galactose and glucose Au nanoparticles were then studied as nanoprobes in cancer cells, tumoral tissues and solid tumors. through confocal Raman microscopy. Theses nanoparticles showed to be suitable nanoprobes in these systems, being able to surpass the known autofluorescence coming from This dissertation showed that nanoparticles can be used as alternative probes to the common fluorophores nowadays used, presenting biocompatibility and specificity. Regarding to the optical techniques used, confocal Raman microscopy showed to be an advantageous alternative to the commonly used ones’.

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Thomaz, André Alexandre de 1980. "Plataforma fotônica integrada e suas aplicações em estudos de quantum dots e processos biológicos". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277466.

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Orientador: Carlos Lenz Cesar
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
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Resumo: A comunidade científica concorda que há grandes chances que a próxima revolução tecnológica virá do controle dos processos biológicos. Grandes mudanças são esperadas, desde como produzimos alimentos até como combatemos as doenças. O controle dos processos biológicos nos permitirá produzir carne sintética para alimentação, produzir biocombustíveis retirando CO2 da atmosfera, produzir órgãos inteiros para transplante e combater de forma eficiente doenças como câncer, por exemplo. Está claro para o nosso grupo que para se obter esses resultados é necessário entender a biologia na sua unidade mais básica: a célula. A partir do entendimento e domínio das reações químicas que acontecem dentro da célula, e mais especificamente do controle do DNA, é que vamos conseguir atingir essas previsões e revolucionar a maneira como vivemos hoje. Com esse pensamento em mente, o objetivo dessa tese foi desenvolver uma plataforma fotônica integrada para estudos de processos celulares. Nós acreditamos que as ferramentas fotônicas são as ferramentas que preenchem todos os requisitos para os estudos de processos celulares, pois possibilitam o acompanhamento dos processos em tempo real sem causar dano as células. As técnicas presentes são: fluorescência excitada por 1 ou 2 fotons, geração de segundo ou terceiro harmônico, pinças ópticas, imagem por tempo de vida da fluorescência e "fluorescence correlation spectroscopy" (FCS). Nesta tese demonstramos como montar essa plataforma integrada e mostramos sua versatilidade com resultados em várias áreas da biologia e também para o estudo de quantum dots.
Abstract: The scientific community believes there is a great chance that the next technological revolution is coming from the control of biological processes. Great changes are expected, from the way we produce food up to the way we fight diseases. The control of biological processes will allow us to produce synthetic meat as food, to produce biofuels extracting CO2 directly from the atmosphere, to produce whole synthetic organs for transplant and to fight diseases, like cancer, in more efficient ways. It is clear to our group that in order to obtain these results it is necessary to understand biology from its most basic unity: the cell. Only from understanding and controlling chemical reactions inside a cell, and more specifically from the DNA controlling, it will be possible to achieve these predictions and cause a revolution in the way we live nowadays. Bearing these thoughts in mind, the objective of this thesis was to develop an integrated photonic platform for study of cellular processes. We believe that photonic tools are the only tools that fulfill all the requeriments for studies of cellular processes because they are capable to follow processes in real time without any damage to the cells. The techniques integrated are: 1 or 2 photon excited fluorescence, second or third harmonic generation, optical tweezers, fluorescence lifetime imaging and fluorescence correlation spectroscopy. In this thesis we demonstraded how to assemble this integrated plataform and we showed its versatility with results from different areas of biology and quantum dots.
Doutorado
Física
Doutor em Ciências

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Sacramento, Patrícia Almada. "Estudo comparativo dos efeitos de antimicrobianos utilizados para a limpeza de cavidades ou incorporados ao sistema adesivo na resistência e degradação da união resina/dentina submetida ao envelhecimento". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288610.

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Orientador: Regina Maria Puppin-Rontani
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Os objetivos nesta tese, apresentada em dois capítulos, foram avaliar o efeito da clorexidina-CHX e do monômero antibacteriano 12-metacriloxidodecilpiridíneo-MDPB na resistência e degradação da união resina/dentina desmineralizada por até doze meses de armazenamento. Capítulo 1: O objetivo deste estudo in vitro foi avaliar o efeito da CHX e/ou de diferentes sistemas adesivos na penetração dos monômeros na dentina desmineralizada, na formação e espessura da camada híbrida utilizando a técnica de Microscopia Confocal de Varredura a Laser (MCVL). Foram utilizados 3 sistemas adesivos: Clearfil SE Bond- SE (Kuraray), Clearfil Protect Bond - PB (Kuraray) e Adper Single Bond 2- SB (3M/ESPE) e um agente antimicrobiano: solução de digluconato de clorexidina 2% (FGM) preconizado para a limpeza da cavidade. Trinta terceiros molares hígidos foram distribuídos aleatoriamente em 6 grupos de acordo com os sistemas adesivos SE, PB e SB, com ou sem aplicação prévia da CHX. A dentina média foi exposta e desmineralizada artificialmente com gel ácido de carboximetilcelulose previamente ao procedimento de união. Os dados de MCVL foram analisados pelo teste estatístico Análise de Variância e teste de Tukey (P<0,05). A CHX e os sistemas adesivos não interferiram com a penetração dos monômeros na dentina desmineraliza. Todas as amostras apresentaram formação de camada híbrida, sendo mais espessa e menos homogênea nos grupos do SB, independente do uso da CHX. Concluiu-se que a CHX e os diferentes sistemas adesivos não afetaram a penetração dos monômeros em dentina desmineralizada. Somente o sistema adesivo interferiu com a espessura e homogeinidade da camada híbrida. Capítulo 2: O objetivo deste estudo in vitro foi: avaliar a influência CHX, do MDPB e o tempo de armazenamento na resistência e degradação da união resina/dentina desmineralizada através do teste de microcisalhamento (µSBS) e análise da nanoinfiltração. Foram utilizados 2 sistemas adesivos: Clearfil SE Bond- SE (Kuraray), Clearfil Protect Bond - PB (Kuraray). Cento e vinte terceiros molares hígidos foram distribuídos aleatoriamente em 12 grupos de acordo com os sistemas adesivos SE e PB, com ou sem aplicação prévia da CHX na superfície de união e tempo de armazenamento de 24 horas, 6 e 12 meses. A dentina média foi exposta e desmineralizada artificialmente. Após 24 horas de armazenamento o SE apresentou os menores valores de µSBS, não havendo diferença após 6 e 12 meses de armazenamento. A CHX não afetou os valores de µSBS. O modo de falha e a avaliação da nanoinfiltração foram analisados de forma descritiva. A nanoinfiltração da interface resina/dentina foi verificada em todos os grupos, havendo maior penetração da prata nos grupos de CHX. Um aumento no depósito de prata e decréscimo nos valores de µSBS foi notado em todos os grupos após 6 meses de armazenamento. A CHX e o MDPB não foram capazes de inibir a nanoinfiltração e o decréscimo na resistência de união. Conclui-se que a CHX não afetou a penetração dos sistemas adesivos na dentina desmineralizada, afetou a formação da camada híbrida, porém, não afetou os valores de resistência de união imediatos, que foram alterados pelo tempo de armazenamento, bem como a nanoinfiltração da prata na interface adesiva, após 6 e 12 meses.
Abstract: The objective of this Thesis, presented in two chapters, was to evaluate the effect of chlorhexidine-CHX and the antibacterial monomer 12-metacriloxydodecylpiridinium-MDPB on the bond strength and bonding degradation of the resin/demineralized dentin interface over twelve months of storage time. Chapter 1: The objective of this in vitro study was to evaluate the effect of CHX and/or different adhesive systems, in the penetration of monomers in demineralized dentin, as well as on the formation and thickness of the hybrid layer using Confocal Laser Scanning Microscopy (CLSM). Three adhesive systems were used: Clearfil SE Bond- (Kuraray), Clearfil Protect Bond - PB (Kuraray) and Adper Single Bond 2 - SB (3M/ESPE), and an antibacterial agent: 2% chlorhexidine solution (FGM) used for cavity disinfectant. Thirty sound third molars were randomly distributed into 6 groups according the adhesive systems SE, PB and SB, with or without previous CHX application. The middle dentin was exposed and the artificial caries lesion was developed with a carboxymethylcellulose acid gel previously the bonding procedure. CLSM images were analysed by the Analysis of Variance and Tukey's post hoc tests (P<0.05). The CHX and the MDPB did not interfere with the penetration of the adhesive systems in demineralized dentin. All the groups presented a hybrid layer formation, with significantly thicker and lower homogeneity in the SB groups, regardless of the CHX application. It was concluded that the CHX and the different adhesive system did not affect the penetration of monomers in the demineralized dentin. Only the adhesive system affected the thickness and homogeneity of hybrid layer. Chapter 2: The objective of this in vitro study was to evaluate the influence of CHX, MDPB and storage time in regard to the bond strength and the bonding degradation of resin/demineralized dentin interface by microshear (µSBS) and nanoleakage evaluation.Two adhesive systems were used: Clearfil SE Bond- SE (Kuraray), Clearfil Protect Bond- PB (Kuraray). One hundred twenty sound third molars were randomly distributed into 12 groups according to the adhesive systems, SE and PB, with or without previous CHX application on the bonding surface, and storage time of 24h, 6 and 12 months. The middle dentin was exposed and a artificial caries lesion was developed artificially. After 24h of storage, the SE groups presented the lower µSBS values, but they did not have statistical significant differences after 6 and 12 months of storage. The failure mode and the nanoleakage were evaluated descripitivelly. The nanoleakage of the resin/dentin interface was verified in all the groups, having a greater silver deposit in the CHX groups. An increase in the silver deposit and decrease in the µSBS values were noticed in all the groups after 6 months of storage. The CHX and the MDPB were not able to inhibit the nanoleakage and a decrease in bond strength. It was concluded that the CHX did not affect the penetration of the adhesive systems in the demineralized dentin, affected the hybrid layer formation, but it did not affect the imediate values of the bond strength, which were modified with the storage time, as was the nanoleakage in bonding interface, after 6 and 12 months.
Doutorado
Odontopediatria
Doutor em Odontologia

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Ferro, Daniela Peixoto 1981. "Aplicação da biofotônica para o estudo de cicatrizes". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312786.

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Orientador: Konradin Metze
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A aplicação integrada de técnicas modernas, como a Geração do Segundo Harmônico (SHG) e os tempos de vida da fluorescência (FLIM), com análise de imagens matemáticas nos permitem visualizar detalhes não vistos por microscopia de luz convencional. O objetivo deste estudo foi investigar se isto também pode ser aplicado para a investigação de tecido cicatricial. Foram estudados 28 casos de preparações histológicas de rotina, de quelóides, cicatrizes hipertróficas e normais. A Fluorescência de dois fótons e SHG foram obtidas por um microscópio multifóton (LSM 780 NLO-Zeiss), em objetiva de 40X e excitados por um laser Mai Tai de Ti: Safira (comprimento de onda de 940 nm). Foram adquiridas imagens em 3D e foram criadas imagens justapostas a fim de comparar diferentes cicatrizes ou várias regiões no interior da mesma cicatriz com análise de imagens informatizadas. Variáveis de Textura derivadas a partir da matriz de coocorrência das imagens de fluorescência mostraram diferenças significativas entre as cicatrizes normais, cicatrizes hipertróficas e quelóides. Para a análise do FLIM, foi utilizado um sistema composto por um microscópio confocal (LSM780-NLO- Zeiss), com objetiva de 40x e um sistema FLIM acoplado. As amostras foram excitadas por um laser de diodo a 405nm. Estudamos secções não coradas de 32 casos processados rotineiramente de tecido cicatricial incluídos em parafina. As áreas das regiões centrais e periféricas foram selecionadas aleatoriamente e comparadas. Os tempos de vida de fluorescência das hemácias serviram como padrão interno. Os tempos de vida do colágeno em áreas centrais em todos os tipos de cicatrizes foram significativamente mais longo do que em áreas periféricas. Houve correlação positiva entre os tempos de vida de fluorescência das hemácias e as fibras de colágeno entre os casos. Em resumo, o SHG e a técnica Flim revelam em cicatrizes rotineiramente processadas, características morfológicas dos tecidos, que não podem ser detectadas por microscopia de luz convencional
Abstract: The integrated application of modern techniques such as Second Harmonic Generation (SHG) and fluorescence lifetime imaging (FLIM) with mathematical image analysis enable us to visualize details not seen by conventional light microscopy. The aim of this study was to investigate whether this could also be true for the investigation of scar tissue. 28 routine histological preparations of keloids, hypertrophic and normal scars were studied. Two-photon fluorescence and SHG was obtained by a multiphoton microscope (LSM 780 NLO-Zeiss (at 40X objective magnification) and a Mai Tai Ti: Sapphire laser with excitation at 940 nm wavelength. 3D reconstructed patchwork images were created in order to compare different scars or various regions inside the same scar with computerized image analysis. Texture variables derived from the co- occurrence matrix of the fluorescence images showed significant differences between normal scars, hypertrophic scars and keloids. For FLIM analysis we used a system composed of a confocal microscope Zeiss LSM780 Upright-NLO with the 40x objective and a FLIM detection system. The samples were excited by a laser diode at 405nm. We studied unstained sections of 32 routinely processed and paraffin-embedded cases of scar tissue. Randomly selected areas of the central and peripheral regions were compared. The fluorescence lifetimes of red blood cells served as internal standard. Lifetimes of collagen in central areas of all scar types were significantly longer than in the periphery. There was a significant positive correlation between the fluorescence lifetimes of red blood cells and collagen fibers among the cases. In summary, SHG and FLIM techniques reveal in routinely processed scar tissue morphological characteristics, which cannot be detected by conventional light microscopy
Doutorado
Biologia Estrutural, Celular, Molecular e do Desenvolvimento
Doutora em Fisiopatologia Médica

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LaCroix, Jeffrey T. Haidekker Mark A. "A fiber-optic confocal scanner for scattering tissue". Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6153.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Mark A. Haidekker. Vita. Includes bibliographical references.

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Al, Dossari Munira. "Confocal microscopic examination of the conjunctiva". Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/18316/1/Munira_Al_Dossari_Thesis.pdf.

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This project has provided a better understanding of the human conjunctiva, the glistening tissue covering the white of the eye, at the cellular level. The observations of this study may serve as a useful marker against which changes in conjunctival tissue due to disease, surgery, drug therapy or contact lens wear can be assessed. Laser scanning confocal microscopy was used to observe and measure characteristics the conjunctiva of healthy human volunteer subjects. It was concluded that this technique is a powerful tool for studying the human conjunctiva and assessing key aspects of the structure of this tissue. The effects of contact lens wear on the conjunctiva can be investigated effectively at a cellular level using this technology.

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Al, Dossari Munira. "Confocal microscopic examination of the conjunctiva". Queensland University of Technology, 2008. http://eprints.qut.edu.au/18316/.

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Abstract (sommario):

This project has provided a better understanding of the human conjunctiva, the glistening tissue covering the white of the eye, at the cellular level. The observations of this study may serve as a useful marker against which changes in conjunctival tissue due to disease, surgery, drug therapy or contact lens wear can be assessed. Laser scanning confocal microscopy was used to observe and measure characteristics the conjunctiva of healthy human volunteer subjects. It was concluded that this technique is a powerful tool for studying the human conjunctiva and assessing key aspects of the structure of this tissue. The effects of contact lens wear on the conjunctiva can be investigated effectively at a cellular level using this technology.

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Naredi-Rainer, Nikolaus [Verfasser]. "Advanced Confocal Microscopy: From Setups To Applications / Nikolaus Naredi-Rainer". München : Verlag Dr. Hut, 2014. http://d-nb.info/1050331907/34.

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40

Garside, John R. "Differential phase confocal microscopy of live biological samples in-vitro". Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362893.

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41

Davies, Owain. "Application of Femtosecond lasers in confocal and scanning tunnelling microscopy". Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/933/.

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This thesis reports the use of a Ti:sapphire ultrafast laser with a confocal microscope to precisely induce DNA damage in the nuclei of live cells by multi-photon absorption, the development and comparison of foci counting algorithms for the quantitative assessment of radiation damage and work towards the development of an ultrafast Scanning Tunnelling Microscopy (STM) technique, employing a Ti:sapphire pulsed laser, called Shaken Pulse Pair eXcitation (SPPX) STM. Measurements of the laser intensity, pulse duration and point spread function are used to estimate the peak intensity at the focus of the confocal microscope. A UV absorption in DNA is excited by the simultaneous absorption of three IR photons (3P). This process leads to the formation of cyclobutane pyrimidine dimmers (CPDs) in the DNA chain. Proliferating Cell Nuclear Antigen (PCNA), involved in the repair of these lesions is tagged with Green Fluorescent Protein (GFP) to visualise the repair process. Damage is detected at peak intensities as low as 23±3 GW/cm2 which is lower than previous studies. PCNA localises at the DNA damage sites with an exponential localisation. Three foci counting algorithms were implemented: a simple intensity threshold algorithm; a Compact Hough transform and Radial Mapping (CHARM) algorithm and a watershed algorithm. The watershed algorithm was particularly effective for the assessment of foci in 3D datasets, providing counts and other properties relating to the foci. It is applied to a study of y-H2AX foci in radiation dosed cells to assess various properties of y-H2AX foci as a function of radiation. Work on the SPPX-STM apparatus led to the development of a novel high frequency translation stage, allowing a retro-reflector to be periodically oscillated without coupling the vibration into the optical table.

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Ghafari, H. "Confocal laser scanning microscopy of nanoparticles applied to immunosorbent assays". Thesis, Nottingham Trent University, 2011. http://irep.ntu.ac.uk/id/eprint/57/.

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The aim of this project was to demonstrate and develop a confocal readout method for fluorescent immunosorbent assays and investigate its potential advantages in comparison to traditional immunoassays. The key point of a confocal immunosorbent assay is the ability to detect the thin layer of immunoassay in the presence of unbound fluorescent reagents without washing the overlayer. Heterogeneous and homogeneous sandwich immunoassays of human IgG model were demonstrated successfully followed by the use of an empirical decomposition method for quantitative separation of the signals of the thin fluorescent assay layer from the overlayer. The detection limits for the homogeneous and heterogeneous formats of the model were 2.2 and 5.5 ng/ml, respectively. The application of confocal microscopy in kinetic analysis of the antigen-antibody reaction of the human IgG model was studied for homogeneous and heterogeneous formats and two fluorescent labels antibodies (FITC and QDs). The association rates of binding of FITC and QD605 conjugated antibodies to human IgG on prepared surfaces were 5.7×104 and 2.6×104 (M-1s-1) respectively. Confocal detection immunosorbent assay enables the detection of more than one assay along the z-axis. By replacing standard substrates with multiple 30 :m layers of substrates, a high density array of immunosorbent assays was created within a stratified medium. Stacks of up to five modified thin mica substrates of model immunoassays were detected by confocal microscopy. When applied to model assays consisting of human and mouse IgGs on different layers, the z-axis multiplexing of immunosorbant assays was demonstrated. The arrays of multiplexed immunosorbent assays were extended to 3D format by using microcontact printing and the assay density was increased twice by detecting the stack of two substrates which each contained two IgGs assays.

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Wang, Xiao. "Confocal angle resolved linear dichroism microscopy for structural fluorescence imaging". Ecole centrale de Marseille, 2013. http://tel.archives-ouvertes.fr/docs/00/87/10/10/PDF/Wang-Thesis.pdf.

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La microscopie de fluorescence a récemment été complétée par une technique appelée dichroïsme linéaire résolu angulairement, basé sur le fait que l'absorption de la lumière est un processus sensible à l'orientation moléculaire. En analysant la réponse d'émission de fluorescence en fonction de l'orientation de la polarisation de la lumière excitatrice, cette technique permet de remonter à l'information d'orientation sur un ensemble de molécules fluorescentes, plus précisément son angle d'orientation moyenne et l'amplitude de ses fluctuations angulaires autour de cette moyenne. Dans cette thèse, nous mettons en oeuvre de nouvelle méthodes et instrumentations capables d'améliorer la robustesse et la rapidité de l'analyse de données de réponses résolues en polarisation, la vitesse de l'acquisition de données, et d'explorer la possibilité de mesurer l'orientation 3D de molécules. Nous proposons une méthode capable de mesurer les propriétés d'orientation de sondes lipidiques fluorescentes par l'utilisation d'un disque de Nipkow couplé à une imagerie par caméra, et combiné avec la modulation rapide de la polarisation par modulateur électro-optique. Une nouvelle méthode de traitement de données est développée pour considérablement améliorer la rapidité et la précision de l'information par une étude des sources de bruit et d'incertitude, dues au bruit et aux facteurs instrumentaux. Cette technique a été testée avec succés sur des vésicules géantes uni-lamellaires et sur cellules vivantes, marquées par les sondes lipidiques DiIC18 et di-8-ANEPPQ. Cette méthode est capable d'acquérir une information précise sur l'orientation moléculaire à une cadence d'une image par seconde. Enfin, afin de sonder de manière non ambiguë l'orientation 3D d'un ensemble de molécules, une nouvelle méthode est proposée, supportée par des simulations numériques, basée sur la variation hors plan de la polarisation d'excitation dans le volume focal par une somme cohérente de champs polarisés linéairement et radialement
Based on the fact that the absorption of light is a molecular-orientation sensitive process, fluorescence microscopy has been recently completed by a technique called angle-resolved linear dichroism. By analyzing the fluorescence emission response with respect to the polarization orientation of the exciting light, this technique allows retrieving orientation information of an ensemble of fluorescent molecules, namely the average orientation angle and the amplitude of the angular fluctuations around this average. In this PhD thesis, we implement new methods and instrumentation tools able to improve the robustness and speed of the polarization resolved data analysis, the rate of the data acquisition, and at last to explore the possibility to record molecular 3D orientation information. A scheme able to monitor the real-time orientation properties of fluorescent lipid probes is proposed using a high-speed spinning disk coupled to camera imaging, combined with fast switching of the polarization state by an electro optical modulator. A new data processing method is developed which considerably improves the speed and the precision of the retrieved information by investigating the sources of bias and uncertainty due to noise and instrumentation factors. The technique has been successfully tested on giant unilamellar vesicles and on living cells labeled with different fluorescent lipid probes, DiIC18 and di-8-ANEPPQ. It was able to acquire precise molecular orientation images at full frame rates in the range of one frame per second. At last in order to probe unambiguously the 3D orientation information of an ensemble of molecules, a new method is proposed and supported by simulations, based on the out-of-plane tuning of the excitation polarization realized in the focusing volume by coherently summing linearly and radially polarized fields

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Umande, Philip Pembe. "Spatial point pattern analysis with application to confocal microscopy data". Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/8569.

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45

Ramshesh, Venkat K. Lemasters John J. "Luminescence lifetime imaging microscopy by confocal pinhole shifting LLIM-CPS". Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1968.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.
Title from electronic title page (viewed Dec. 11, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Biomedical Engineering." Discipline: Biomedical Engineering; Department/School: Medicine.

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Robic, Julie. "Automated characterization of skin aging using in vivo confocal microscopy". Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1069/document.

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La microscopie confocale de réflectance in-vivo (RCM) est un outil puissant pour visualiser les couches cutanées à une résolution cellulaire. Des descripteurs du vieillissement cutané ont été mis en évidence à partir d'images confocales. Cependant, leur évaluation nécessite une analyse visuelle des images par des dermatologues expérimentés. L'objectif de cette thèse est le développement d'une technologie innovante pour quantifier automatiquement le phénomène du vieillissement cutané en utilisant la microscopie confocale de réflectance in vivo. Premièrement, la quantification de l’état de l’épiderme est abordée. Ensuite, la jonction dermique-épidermique est segmentée, et sa forme est caractérisée. Les mesures proposées mettent en évidence une différence significative entre les groupes d'âge et l’exposition au soleil. Enfin, les méthodes proposées sont validées par des études cliniques et d'efficacité de produits cosmétiques
In-vivo reflectance confocal microscopy (RCM) is a powerful tool to visualize the skin layers at cellular resolution. Aging descriptors have been highlighted from confocal images. However, it requires visual assessment of images by experienced dermatologists to assess those descriptors. The objective of this thesis is the development of an innovative technology to automatically quantify the phenomenon of skin aging using in vivo reflectance confocal microscopy. First, the quantification of the epidermal state is addressed. Then, the Dermal-Epidermal Junction is segmented, and its shape is characterized. The proposed measurements show significant difference among groups of age and photo-exposition. Finally, the proposed methods are validated through both clinical and cosmetic product efficacy studies

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Perrot, Jean-Luc. "Explorations optiques multimodales et multiéchelles non invasives appliquées au revêtement cutanéomuqueux , étendues à l'appareil oculaire antérieur". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSES010/document.

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Après une introduction brève de l’historique de l’imagerie dermatologique non invasive, ce travail est divisé 3 parties. 1) Présentation d’un projet de développement d’un tomographe à cohérence optique miniaturisé, peu onéreu devant permettre une diffusion de cette technique aux dermatologues exerçant en dehors des hôpitaux. Il s’agi d’un projet ANR DOCT-VCSEL Portable Optical Coherence Tomography with MEMS-VCSEL swept- sources for skin analysis ANR 2015 / Défi sociétal « Vie, Santé et Bien-Etre » Axe 13 « Technologies pour la santé » 2) Présentation d’un projet dont le but est l’identification de lésions cutanées cancéreuses au moyen d’un nouvel OCT haute définition développé par la société DAMAE, issue de l’Institut supérieur d’Optique de Palaiseau. Il s’agit d’un dispositif qui sera dans un premier temps réservé aux centre d’excellence en imagerie dermatologique. 3) la reprise des 52 publications ayant trait à l’imagerie cutanée auxquelles j’ai participé et référencées dans les bases de données internationales au 31 décembre 2016. Ce travail couvre l’ensemble de l’imagerie non invasive dermatologique moderne et aborde des sujets qui n’avaient jamais été étudié de la sorte. Notamment les muqueuses et l’appareil oculaire antérieur mais aussi l’identification par microscopie confocale des marge chirurgicales ou l’association microscopie confocale spectrométrie Raman
After a brief introduction to the history of non-invasive dermatological imaging, this work is divided into 3 parts. 1) Presentation of a project for the development of a low-cost miniaturized optical coherence tomograph to allow dissemination of this technique to dermatologists practicing outside hospitals. This is an ANR project: DOCT-VCSEL Portable Optical Coherence Tomography with MEMS-VCSEL swept-sources for skin analysis ANR 2015 / Societal Challenge "Life, Health and Welfare" Axis 13 “Technologies for Health" 2) Presentation of a project whose goal is the identification of cancer skin lesions by means of a new high definition OCT developed by the company DAMAE, resulting from the Higher Institute of Optics of Palaiseau. It is a device that will initially be reserved for centers of excellence in dermatological imaging. 3) Presentation of 52 publications related to skin imaging, in which I participated, and referenced in the international databases as of December 31, 2016. This work covers all modern dermatological non-invasive imaging and addresses Subjects that had never been studied in this way. Notably the mucous membranes and the anterior ocular apparatus but also the identification by confocal microscopy of the surgical margins or the association confocal microscopy Raman spectrometry

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Nemet, Boaz Alfred. "Measuring fluid properties on a microscopic scale using optically trapped microprobes /". Thesis, Connect to Dissertations & Theses @ Tufts University, 2001.

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Thesis (Ph.D.)--Tufts University, 2001.
Adviser: Mark Cronin-Golomb. Submitted to the Dept. of Electrical Engineering. Includes bibliographical references (leaves 16-18). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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49

Guimarães, Bruno Martini. "Influência da agitação de 4 cimentos com ultrassom na capacidade seladora, penetrabilidade dentinária e qualidade da obturação pela técnica da condensação lateral ativa". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/25/25147/tde-02092013-162144/.

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Avaliou-se a adaptação da obturação às paredes do canal, a penetrabilidade dos cimentos nos túbulos dentinários, a qualidade da obturação e a capacidade seladora utilizando-se quatro cimentos obturadores a base de resina epóxi (AH Plus, AcroSeal, AdSeal e Sealer 26), quando submetidos a agitação ultrassônica no momento da inserção do cimento. Foram utilizados 84 caninos humanos recém extraídos, unirradiculados e que foram divididos em dois grupos A e B (n=40), sendo que cada grupo foi dividido em quatro subgrupos de 10 dentes cada, conforme o cimento empregado: A1 e B1 - AH Plus, A2 e B2 Acroseal, A3 e B3 Adseal e A4 e B4 Sealer 26. O preparo biomecânico foi efetuado utilizando-se de instrumentação rotatória com sistema ProTaper, determinando um batente apical com o instrumento F5 (50.05) no comprimento real de trabalho. Foi realizada, em todos os dentes, a padronização do forame até o instrumento Protaper F3. Em seguida, os cimentos foram corados com a Rodamina B. Os canais foram então obturados por meio da técnica da condensação lateral, sendo os canais do grupo A previamente preenchidos pelos cimentos obturadores e submetidos à agitação ultrassônica enquanto que os do grupo B foram considerados como controle e não foram submetidos a agitação. Os dentes então foram submetidos ao teste de infiltração de fluídos após 7 e 30 dias de realizada a obturação. Após esse período, foram realizadas três secções transversais a 2, 4 e 6 mm do ápice e as imagens das secções foram obtidas em estereomicroscópio e microscopia a laser confocal. Para análise entre grupos, no período de 7 e 30 dias em relação ao teste de infiltração apical, foi selecionado o teste não-paramétrico de Kruskall-Wallis e Dunn (p<0.05). Para as demais análises, foi utilizado o teste não-paramétrico Mann Whitney e Wilcoxon. Os resultados indicaram que a agitação ultrassônica aumentou a infiltração apical de forma significante para o cimento AH Plus no período de 7 dias. No que diz respeito à penetração de cimento na dentina, houve um aumento significante para os cimentos AHPus, Acrosela e Sealer 26 no terço médio, e para o AH Plus e Sealer no terço cervical. Com relação às fendas, a agitação ultrassônica favoreceu menor presença desta para o AH Plus na porção apical, e para todos os cimentos na região média e cervical. Concluiu-se que a agitação ultrassônica não proporcionou melhorias no selamento apical e favoreceu maior penetração de cimento na dentina e menor presença de fendas na região média e cervical.
The aim of this study was to evaluate the adaptation of the filling of the canal walls, the penetration of cements in the dentinal tubules, the quality of the filling and sealing capacity utilizing four different epóxic based sealers (AH Plus, Acroseal, AdSeal and Sealer 26), when submitted to ultrasonic agitation at the time of the obturation. Eighty four extracted uniradicular human canines were utilized, and they were divided into two experimental groups A and B (n = 40), and each group was divided into four groups of 10 teeth each, in accordance with the cement used: A1 and B1 - AH Plus, A2 and B2 - Acroseal, A3 and B3-Adseal and A4 and B4 - Sealer 26. The biomechanical preparation was performed utilizing rotary instrumentation with theProTaper system, determining an apical stop with a F5 instrument (50.05) in the real working length. The standardization of the foramen was performed on all teeth until the Protaper F3 instrument. The cements were stained with Rhodamine B. Next the canals were filled by the lateral condensation technique. The canals of group A were previously filled by the sealers and submitted to ultrasonic agitation while those in Group B were considered as the controls and were not subjected to agitation. The teeth were then submitted to testing for leakage of fluids 7 and 30 days after the obturation. After this period, three transverse cross sections were performed at 2, 4 and 6 mm from the apex and the images of the sections were obtained in a stereomicroscope and confocal laser microscopy. For the analysis between the groups, in the period of 7 and 30 days, in relation to the apical leakage test, was selected the nonparametric Kruskal-Wallis and Dunn tests (p <0.05). For the other analyzes, the nonparametric Mann Whitney and Wilcoxon tests was used. The results indicated that the ultrasonic agitation significantly increased apical leakage for the AH Plus in the period of 7 days. With regard to the penetration of the cement into the dentin, there was a significant increase for the AHPus, Acroseal and Sealer 26 cements in the middle third, and the AH Plus and Sealer 26 in the cervical third when the ultrasonic agitation was performed. Regarding the cracks, the ultrasonic agitation favored a smaller presence for the AH Plus in the apical portion, and for all cements in the middle region and cervical. It was concluded that the ultrasonic agitation did not improve the apical seal and favored greater penetration of cement into the dentin and less presence of cracks in the middle and cervical region.

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Costa, Neto Paulo Fermino da. "Efeito de diferentes materiais e términos de preparo sobre a integridade marginal de coroas CAD/CAM /". Araraquara, 2019. http://hdl.handle.net/11449/182392.

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Orientador: José Roberto Cury Saad
Resumo: A crescente demanda por tratamentos estéticos tem impulsionado o desenvolvimento de novos materiais e técnicas para tratamentos restauradores. Este estudo teve como objetivo avaliar o efeito de diferentes materiais restauradores e términos de preparo sobre a integridade marginal de coroas unitárias confeccionadas pelo sistema CAD/CAM (Computer Aided Desing/Computer Aided Manufacturing). Quarenta coroas unitárias foram confeccionadas utilizando quatro materiais: cerâmica vítrea a base de dissilicato de lítio (IPS e.max CAD, Ivoclar Vivadent), composto híbrido a base de cerâmica feldspática reforçada com polímeros (Vita Enamic, Vita Zahnfabrik), cerâmica de silicato de lítio reforçada com zircônia (Vita Suprinity, Vita Zahnfabrik) e compósito vítreo nanohíbrido (Brava Blocks, FGM) a partir de um preparo com quatro términos diferentes: chanfro (espessura de borda 0.8 mm), chanfro raso (0.4 mm), chanfro profundo (1.2 mm) e ombro (1.2 mm). O dente preparado foi escaneado com um scanner intraoral (CEREC Omnicam, Dentsply Sirona) e um projeto de restauração foi confeccionado com o uso de um software (CEREC SW 4.4, Dentsply Sirona). As coroas foram obtidas a partir da fresagem (Dental Milling Machine MC XL, Dentsply Sirona) de blocos para CAD/CAM dos materiais incluídos no estudo. Em seguida, as coroas obtidas a partir de dois materiais (IPS e.max CAD e Vita Suprinity) foram levadas a forno (Programat CS2The, Ivoclar Vivadent) para queima de cristalização. A integridade de borda das ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The crescent demand for aesthetic treatments has driven the development of new materials and techniques for restorative treatments. The aim of this study was to evaluate the effect of different restorative materials and finish line designs on the marginal integrity of single crowns obtained by CAD/CAM (Computer Aided Desing/Computer Aided Manufacturing). Forty crowns were made using four materials: Lithium disilicate-based vitreous ceramics (IPS e.max CAD, Ivoclar Vivadent), hybrid composite based on polymere-reinforced feldspathic ceramics (Vita Enamic, Vita Zahnfabrik), silicate ceramics lithium reinforced with zirconia (Vita Suprinity, Vita Zahnfabrik) and composite vitreous nanohybrid (Brava Blocks, FGM) from a preparation with four different finish line designs: chamfer (0.8 mm edge thickness), shallow chamfer (0.4 mm), deep chamfer (1.2 mm) and shoulder (1.2 mm). The prepared tooth was scanned with an intraoral scanner (CEREC Omnicam, Dentsply Sirona) and a restoration project was made using a software (CEREC SW 4.4, Dentsply Sirona). Crowns were obtained from milling (Dental Milling Machine MC XL, Dentsply Sirona) from CAD/CAM blocks of materials included in the study. Then, the crowns obtained from two materials (IPS e.max CAD and Vita Suprinity) were submitted (Programat CS2The, Ivoclar Vivadent) for burning of crystallization. The marginal integrity of the crowns was measured using the Laser Confocal Scanning Microscope (Lext OLS 4100, 3D measuring laser microscope,... (Complete abstract click electronic access below)
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