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Gao, Bo. "Multigrid reconstruction of micro-CT data". Thesis, KTH, Skolan för teknik och hälsa (STH), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211180.
Pełny tekst źródłaSen, Sharma Kriti. "Compressed Sensing based Micro-CT Methods and Applications". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/52866.
Pełny tekst źródłaPh. D.
Sharma, Yash. "Automated fibre segmentation in micro CT images of paper". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50044.
Pełny tekst źródłaApplied Science, Faculty of
Mechanical Engineering, Department of
Graduate
Zainon, Rafidah Binti. "Spectral Micro-CT Imaging of Ex Vivo Atherosclerotic Plaque". Thesis, University of Canterbury. Physics and Astronomy, 2012. http://hdl.handle.net/10092/7165.
Pełny tekst źródłaOpie, Alexander M. T. "Contributions to spectral CT". Thesis, University of Canterbury. Electrical and Computer Engineering, 2013. http://hdl.handle.net/10092/8532.
Pełny tekst źródłaGomes, Mauricio Neves. "Desproteinização do esmalte associada à técnica de remineralização no clareamento em consultório". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/23/23140/tde-30112011-164218/.
Pełny tekst źródłaPurpose: To evaluate color, gloss, roughness and ultrastructural changes of enamel bleached with 35% hydrogen peroxide, subjected to previous treatment with deproteinized agent, or later treatment with remineralizing agent casein phosphopeptide-amorphous calcium phosphate (CPP-ACP). Materials and Methods: The experimental groups were: GC (control + in-office): 35% H2O2 - 4 sessions of 8 min; GE1(primer+in-office): 5.25% NaOCl during 1 min before the application of 35% H2O2 as done in GC, and GE2 (in-office+ACP-CPP): GC + ACP-CPP, daily applied during 7 days. Enamel and dentin blocks (n=8), obtained from bovine tooth, were used to evaluate color, gloss and roughness. Color changes (E), L* and b* parameters were done with a colorimeter and surface gloss with a glossimeter, before, immediately after (1h), 4 and 7 days after treatment. Roughness parameters, Ra, RT and Rsm, were done with a contact perfilometer before, immediately after and 7 days after treatments. ANOVA two-way and Tukeys test were performed to evaluate E, gloss and roughness separately (p=0.05). To access human pre-molar ultrastructural changes, teeth were cross-sectioned buccal-lingual and disto-mesio observed by scanning electron microscope, field emission gun, EDS to quantify chemical elements. Enamel three-dimensional images were analysed with microcomputed tomography (micro-CT) with resolution 11,24m (n=8). Structural parameters were analyzed: structural thickness (St.Th.), structural separation (St.Sp.) and fragmentation index (Fr.I.) before and after treatments in two regions of interest:ROI 1= 56,2m and ROI 2= 110,2 m, both from buccal surface. Paired t-test was done for analyses of each structural parameter. Results: There was no statistical difference among surface treatments to E, Ra and Rsm. Immediately after bleaching (1h) occured highest L* increase and decrease of surface gloss which remained until 7 days. Deproteinized agent applied on bovine tooth not emphasized enamel gloss reduction, but the CPP-ACP has resulted in a higher gloss reduction and roughness increase (Rt parameter) after 7 days. Deproteinized agent application previous to in- office bleaching observed a smooth surface, without structural parameters changes. There is a greater calcium quantity, forming a cover mantle after CPP-ACP application around enamel prisms, St.Th increase of 4,1m, less spacing between hydroxyapatite crystals and reductions of St.Sp of 0,8 m and Fr.I of 0,01 on ROI-1 after 7 days. Conclusion: Application of deproteinized agent does not change bovine enamel color, gloss and human enamel inorganic ultrastructure. CPP-ACP application after in-office bleaching does not contribute to color change, but decrease gloss of bovine enamel and change human enamel outermost ultrastructure portion after 7 days.
Iglecias, Elaine Faga. "Avaliação qualitativa e quantitativa da instrumentação e obturação de canais radiculares achatados utilizando-se microtomografia computadorizada". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/23/23145/tde-19022015-172359/.
Pełny tekst źródłaEndodontics in the microtomography (CT) has been widely used as a method for three-dimensional analysis. Currently, three mechanized movements for root canal preparation has been introduced in endodontic, oscillatory, rotational and reciprocal routine. There are different files systems driven by motors capable of these movements. Thus, the objectives of this work are using CT to evaluate, in flattened mesial canals of mandibular molars, the quality and final modeling of root canal preparation, using oscillatory, reciprocal and rotational systems and evaluate the root canal filling with single cone or continuous waves of condensation, with respect to the volume of filling material and voids. The results showed no significant difference in estatísitica wear volume between the tested groups. For the percentage of untreated surface and the oscillating rotating groups played more walls in the cervical and middle thirds of the reciprocal group. The technique of continuous wave of condensation and single cone showed similar fillings fill in the middle and apical thirds, and in the cervical third of the technique of continuous wave left lower percentage of voids.
Robertson, Galen Charles. "Quantification of Skeletal Phenotype Using Micro-CT and Mechanical Testing". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4874.
Pełny tekst źródłaCahoon, Lindsey Charlene. "Micro-CT Inspection of Impact Damage in Carbon/Epoxy Rods". BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6350.
Pełny tekst źródłaSERRA, FRANCESCA GIULIA. "Bone-like inducing grafts: in vivo and micro-CT analysis". Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2858349.
Pełny tekst źródłataha, Nada. "3D RECONSTRUCTION OF MICRO CT IMAGES FOR SINGLE PHOTON PROCESSING SYSTEM". Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-20028.
Pełny tekst źródłaDavid, Alfaro. "Micro-CT measurement of the internal fit of lithium disilicate crowns". Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44929.
Pełny tekst źródłaQaseminejad, Raeini Ali. "Modelling multiphase flow through micro-CT images of the pore space". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11617.
Pełny tekst źródłaBritton, Steven Todd. "AN ANALYSIS OF INTERNAL VOIDS OF ORTHODONTIC ADHESIVES VIA MICRO-CT". Master's thesis, Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/598784.
Pełny tekst źródłaM.S.
Objectives: While bracket debonding has been explored through shear bond-strength tests with debonding linked to the type of material used, the technique of adhesive application, and contamination, the contribution of internal voids in orthodontic adhesives is unknown. Voids may result in fracture or bond-failure, either within the adhesive or at the tooth-adhesive-bracket interfaces. The aim of this thesis is to quantify the internal volumetric voids and bonding strength of three generations of bracket adhesives. Methods: Extracted third molars were bonded with three groups of orthodontic brackets including conventionally-pasted (CP), pre-coated (PC), or pre-coated flash-free (FF) (n=5 per group). The three-dimensional internal structure of the adhesive was evaluated with Micro Computed Tomography (micro-CT) using the Skyscan micro-CT (maximum resolution of 5 microns). Data from the micro-CT were analyzed with SkyScan software to perform 3D reconstructions, image processing, and qualitative and quantitative analysis of the adhesive’s structure. The amount of void was determined by measuring the percentage of voids at the bonded interfaces (Vint) and within the adhesive (Vbulk). The total amount of void was also calculated (Vtot= Vint+ Vbulk). Differences in void between the groups were assessed using one-way ANOVA with post-hoc Tukey tests (α=0.05). The bonding strength of the three adhesives systems was evaluated via shear bond strength tests. Results: Our void quantification results showed that FF brackets had a statistically higher (p0.05) for any the analyzed locations (Vint, Vbulk). Our results indicate the majority of voids were found at bonded interfaces (Vint) compared to within the bulk (Vbulk) for all three groups, with statistically significant (p<0.05) differences for CP and FF. Our bonding strength evaluation revealed the pre-coated group (PC) to have on average the highest bond strength compared to conventionally-pasted (CP) and pre-coated flash-free (FF) groups. Conclusions: The overall amount of void in the pre-coated flash-free adhesive brackets is significantly higher compared to conventionally-pasted and pre-coated groups. The majority of the void was identified to be located at the bonded interfaces (tooth/adhesive and bracket/adhesive) rather than within the bulk of the adhesive for all groups. Our bonding strength results indicate the pre-coated brackets to have the highest bond strength compared to pre-coated flash-free and conventionally-pasted. Our preliminary set of results indicate an inverse relationship between bonding strength and amount of void of brackets adhesives, with the pre-coated exhibiting the highest bond strength and least void. However, due to a limited sample size additional data are needed to validate these conclusions and find solid relationships between adhesive voids and bonding strength.
Temple University--Theses
Liu, Fanxiao [Verfasser], i Peter [Akademischer Betreuer] Müller. "Micro-CT and Micro-FE analysis of stress transfer of femoral stems / Fanxiao Liu ; Betreuer: Peter Müller". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1228270732/34.
Pełny tekst źródłaBennett, James. "Hybrid Spectral Micro-CT: System Implementation, Exposure Reduction, K-edge Imaging Optimization, and Content Management". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/25525.
Pełny tekst źródłaPh. D.
Michelon, Carina. "EFICÁCIA DA ATIVAÇÃO ULTRASSÔNICA PASSIVA DO SOLVENTE NA REMOÇÃO DE MATERIAL OBTURADOR DURANTE O RETRATAMENTO ENDODÔNTICO ANÁLISE POR MICROTOMOGRAFIA COMPUTADORIZADA". Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/6106.
Pełny tekst źródłaThe removal of pre-existing root canal filling is basic requirement for endodontic retreatment in order to reveal necrotic tissue debris and bacteria which may be responsible for periapical inflammation and by the treatment failure. The aim of this study was to evaluate the efficacy of passive ultrasonic activation (PUA) with use of organic solvent as an assistant method in removal of filling material during endodontic retreatment and determine a protocol for its utilization, using high-resolution micro-Computed Tomography (micro-CT). Thirty curved mesial roots of mandibular molars with isthmus area were instrumented and filled with gutta-percha and EndoFill (Dentsply-Maillefer, Ballaigues, Switzerland) through Tagger s hybrid technique. After 30 days, the filling material was removed with the ProTaper Retreatment rotary system (Dentsply-Maillefer, Ballaigues, Switzerland) and the root canals were prepared with the F1-F4 ProTaper instruments (Dentsply-Maillefer, Ballaigues, Switzerland). The specimens will be randomized into two groups according to the final irrigation protocol. In the Manual Group, the root canals were irrigated and agitated manually with Orange Oil solvent (Citrol, Biodinâmica, Ibiporã, Brazil), 2,5% Sodium Hypochlorite (NaOCl) (Biodinâmica, Ibiporã, Brazil) and 17% Ethylenediaminetetraacetic Acid (EDTA) (Biodinâmica, Ibiporã, Brazil). In the PUA Group, the specimens were submitted to PUA with Orange Oil solvent, 2,5% NaOCl and 17% EDTA. High-resolution micro-CT scans was used to select the sample, analyze the root filling and measure the volume of the remaining root filling material after each stage of the retreatment. The volume of remaining filling material was established and transformed into percentage in relation to total volume of filling material. The dates were statistically analyzed with a significance level set at α = 0.05. The Mann Whitney test was used to compare the percentage of remaining filling material between groups, for canal thirds in each retreatment step. The Friedman test was used to verify differences among root filling material and the successive retreatment stages at each canal segment in same group. The differences amongst the coronal, middle and apical third in the each group were analyzed with Friedman test. The Dunn test was performed as the post-hoc multiple comparison method. No significant differences between groups when rotary instrumentation (Stage 1) was considered (P > 0.05). None of the irrigation protocols removed completely the remains of the root canal filling. The use of Manual e PUA protocols decreases statistically the amount of remaining filling material compared to Stage 1 (P = 0.000). In the PUA Group, the root canals showed significantly less percentage remaining filling material compared with Manual Group, for all thirds (P < 0.05). The PUA protocol left similar amount of filling material among the apical, middle and cervical thirds (P > 0.05). None of the irrigation protocols tested was able to completely remove all gutta-percha/sealer from the curved canals and with isthmus area. However, the results of this study suggest that in root canals with complex anatomy that require endodontic retreatment, the PUA with orange oil, NaOCl and EDTA can be a great aid in the removal of the remaining root filling material left after removal of the bulk of filling material.
A remoção do material obturador pré-existente é um requisito fundamental para a realização do retratamento endodôntico a fim de revelar restos de tecido necrótico e bactérias que podem ser responsáveis pela inflamação periapical e pela falha do tratamento. O objetivo deste estudo foi avaliar a eficácia da Ativação Ultrassônica Passiva (AUP) com uso de solvente orgânico, como um método auxiliar na remoção do material obturador durante o retratamento endodôntico e determinar um protocolo para sua utilização, através da Microtomografia Computadorizada (micro-CT). Trinta raízes mesiais curvas e com istmo de dentes molares inferiores foram instrumentadas e obturadas com guta percha e cimento EndoFill (Dentsply-Maillefer, Ballaigues, Suíça) através da técnica híbrida de Tagger. Após 30 dias, o material obturador foi removido com o sistema rotatório de desobturação ProTaper Retratamento (Dentsply-Maillefer, Ballaigues, Suíça) e o canal repreparado com os instrumentos F1-F4 do sistema rotatório ProTaper Universal (Dentsply-Maillefer, Ballaigues, Suíça). Os espécimes foram aleatoriamente divididos em dois grupos (n=15) de acordo com o protocolo de irrigação final. No Grupo Manual, os canais radiculares foram irrigados e agitados manualmente com solvente a base de Óleo de Laranja (Citrol, Biodinâmica, Ibiporã, Brasil), Hipoclorito de Sódio (NaOCl) 2,5% (Citrol, Biodinâmica, Ibiporã, Brasil) e Ácido Etilenodiaminotetracético (EDTA) 17% (Citrol, Biodinâmica, Ibiporã, Brasil) . No Grupo AUP, os espécimes foram submetidos à AUP com Óleo de Laranja, NaOCl 2,5% e EDTA 17%. A seleção da amostra, a análise da obturação e a mensuração do volume de material obturador remanescente após cada estágio do retratamento foram realizadas através da micro-CT. O volume de material obturador remanescente foi estabelecido e transformado em porcentagem em relação ao volume total de material obturador. Os dados foram submetidos à análise estatística com nível de significância fixado em α = 0.05. O teste de Mann Whitney foi usado para comparar a porcentagem de material obturador remanescente entre os grupos, em cada fase do retratamento. O teste de Friedman foi usado para analisar diferenças entre o volume da obturação e os estágios do retratamento dentro de um mesmo grupo. Diferenças entre os terços cervical, médio e apical dentro do mesmo grupo foram analisadas com o teste de Friedman. O teste de Dunn foi usado como post hoc para múltiplas comparações. Não houve diferença estatisticamente significante entre os grupos quando a instrumentação rotatória (Estágio 1) foi considerada (P > 0.05). Nenhum dos protocolos de irrigação removeu completamente os remanescentes de material obturador em todos os espécimes. Tanto o protocolo da AUP quanto o Manual diminuíram a quantidade de remanescente de guta percha e cimento em relação ao Estágio 1 (P = 0.001). No grupo AUP, os canais radiculares mostraram significantemente menos porcentagem de remanescentes de material obturador que o grupo Manual, para todos os terços (P < 0.05). O protocolo da AUP deixou quantidade similar de material remanescente em todos os terços do canal radicular (P > 0.05). Nenhum dos protocolos de irrigação testados foi capaz de remover completamente a guta percha/cimento de canais radiculares curvos e com área de istmo. Contudo, os resultados obtidos neste estudo sugerem que em canais radiculares com anatomia complexa que necessitam de retratamento endodôntico, a AUP com óleo de laranja, NaOCl e EDTA pode ser um grande auxiliar na remoção dos remanescentes de material obturador deixados após a desobturação do canal radicular.
Pichotka, Martin Peter [Verfasser], i Caroline [Akademischer Betreuer] Röhr. "Iterative CBCT reconstruction-algorithms for a spectroscopic Medipix-Micro-CT = Iterative CBCT Rekonstruktions-Algorithmen für ein spektroskopisches Medipix-Mikro-CT". Freiburg : Universität, 2014. http://d-nb.info/1115495674/34.
Pełny tekst źródłaStjärnesund, Johan. "A micro-CT investigation of density changes in pressboard due to compression". Thesis, Uppsala universitet, Tillämpad mekanik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-350876.
Pełny tekst źródłaKabini, S. N. "An in-vitro comparative micro-computed tomographic evaluation of three obturation systems". University of the Western Cape, 2017. http://hdl.handle.net/11394/6312.
Pełny tekst źródłaGaps or voids between walls of root canal and obturation material may lead to re-infection of the obturated root canal. Therefore, adaptation of the obturation material to dentine walls is essential for the success of root canal treatment.
Sório, Ana Luisa Riul. "Avaliação histológica e microtomográfica do efeito de células osteoblásticas originárias da medula óssea em defeitos ósseos na calvária de ratos submetidos a um modelo experimental de osteorradionecrose". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/58/58138/tde-30082017-090138/.
Pełny tekst źródłaOsteoradionecrosis is a serious and debilitating consequence of head and neck radiotherapy, defined as a bone area that does not repair after irradiation. The purpose of this investigation was to analyze in vivo the presence of mesenchymal cells from bone marrow in calvariae defects of rats submitted to osteoradionecrosis. Cells were collected from rat femur bone marrow to perform characterization of osteoblastic phenotype by means of biochemical assays such as cell proliferation, alkaline phosphatase activity and its in situ detection and mineralization. Afterwards, male wistar rats were submitted to osteoradionecrosis protocol (20 Gy in a single dose) and paired with control animals. After 30 days, there were performed calvariae defects and placement of osteoblastic cells previously cultured with a gel vehicle inside the defects, which were sutured properly. The animals were divided in 4 groups: control (C), control + osteoblastic cells (CC), osteoradionecrosis (IR) osteoradionecrosis + osteoblastic cells (Irc). After 30 days, the animals were euthanized to perform the following analysis: (1) Histological evaluation by means of decalcified slide sections stained with hematoxilin-eosin and Masson trichrome; (2) Tomographic evaluation by means of adequate parameters. Data obtained were submitted to normality test and statistical analysis for p<0,05. The mesenchymal cells from bone marrow presented osteoblastic phenotype after being cultured in osteogenic medium, with higher ALP detection and activity, as well as an increase of mineralized nodules when compared to cells cultured in basal medium. Histological analysis showed that irradiation impaired bone neoformation and affected bone marrow composition, as well as the presence of osteoblasts and osteocytes. On the other hand, cell therapy in group IRc improved bone neoformation when compared to group IR, showing similarity to control groups. Tomographic analysis revealed an increase in trabecular thickness, density of connectivity, trabecular number and bone surface when compared to group IR. The results suggest that the placement of mesenchymal cells differentiated in osteoblasts may improve bone neoformation of defects created after the onset of osteoradionecrosis.
Al, Jamaan Tamer Saleh. "Diagnostic accuracy and reproducibility of conventional and novel caries detection methods as determined by histology and micro-CT : a study in vitro". Thesis, University of Dundee, 2016. https://discovery.dundee.ac.uk/en/studentTheses/8aee92e0-8af5-4815-b67b-96de1088e07d.
Pełny tekst źródłaTaylor, Howard. "Assessing the potential for suffusion in sands using X-ray micro-CT images". Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/56070.
Pełny tekst źródłaKim, Paul [Verfasser]. "In-vitro-Untersuchung des Pulpenraums mandibulärer primärer Prämolaren im Micro-CT / Paul Kim". Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2020. http://d-nb.info/1224810201/34.
Pełny tekst źródłaMcMurray, Alexis Kelly. "Micro-CT/PET Assessment of Lung Metastasis in a Mouse Model of Osteosarcoma". The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1364308724.
Pełny tekst źródłaStarnoni, Michele. "Modelling single and two-phase flow on micro-CT images of rock samples". Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=232293.
Pełny tekst źródłaHopper, Timothy Andrew John. "Quantitative MRI and Micro-CT of bone architecture : applications and limitations in orthopaedics". Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16149/1/Timothy_Hopper_Thesis.pdf.
Pełny tekst źródłaHopper, Timothy Andrew John. "Quantitative MRI and Micro-CT of Bone Architecture: Applications and Limitations in Orthopaedics". Queensland University of Technology, 2005. http://eprints.qut.edu.au/16149/.
Pełny tekst źródłaInness, Philip Ralph Patton. "Assessment of different contrast preparations for micro-computed tomographic microangiographic assessment of canine cadaveric hindlimbs". Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/27503.
Pełny tekst źródłaPan, Lei. "The earliest members of the genus Homo in South Africa : evidence from inner structure of lower postcanine dentition". Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30087/document.
Pełny tekst źródłaThis thesis consists of two individual projects and six chapters, which are based on the examination of dental inner structure of lower postcanine dentition in a number of fossil and modern specimens, through which a comprehensive study has been done using micro-computed tomography and computer-assisted paleonanthropology tools. We first documented and assessed the taxonomical value of enamel thickness and 3D whole-crown enamel thickness distribution patterns in a number of earliest members of the genus Homo in South Africa, and looked into the taxonomic relavence of EDJ morphology along postcanine dentition, and discussed the possible adaptive/developmental factors that account for the variation of EDJ morphology we observed here. The first three chapters (Introduction, Materials and Methods) provide an overview of the objectives of this thesis, and review previous studies. Also, they provide a detailed introduction of fossil materials, sites and a background of computer-aided method (micro-XCT) to analyze the dental inner structure. The Results chapter comprises of two independent research papers, in different stages of submission and publication. The Results and Discussion chapters offer an extensive summary of enamel thickness, EDJ geometric morphometrics and 3D-EDJ metameric variation between species, and compare the results with a number of morphological and developmental studies, and provide an outlook of future study. The last chapter reaches the conclusive points of this thesis, it highlights the taxonomical value of premolar EDJ, and emphasizes the mosaic features of the dentition of South African early Homo
Cheng, Linda Lam. "Repair of root resorption four and eight weeks following the application of continuous light and heavy forces for four weeks: micro-ct and histology studies". Thesis, Faculty of Dentistry, 2007. http://hdl.handle.net/2123/4308.
Pełny tekst źródłaBallard, Darin J. "Properties of root cementum: part 11 continuous versus intermittent controlled orthodontic forces on root resorption. a micro-ct study". Thesis, Faculty of Dentistry, 2006. http://hdl.handle.net/2123/4307.
Pełny tekst źródłaMay, Catherine M. "Craniofacial Bone Density is Regulated by Thyroid Hormone in Zebrafish:". Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108815.
Pełny tekst źródłaThyroid hormone (TH) facilitates developmental transitions, particularly by modulating cell proliferation and differentiation. Its role in regulating skeletal growth is well documented. Previous work from our lab and others have demonstrated that hypo- and hyperthyroid fish display changes in bone shape, ossification and the timing of ossification5. Zebrafish (Danio rerio) develop bone quickly, grow indefinitely throughout their lives, are highly amenable for imaging, and are a valuable model for skeletal biology research. Using Danio rerio, we sought to study the long-term effects of TH on bone density by rearing and comparing normal euthyroid (Eu) with a transgenically thyroid-ablated hypothyroid (TH-) and mutant hyperthyroid (TH+) fish. We found that TH strongly affects bone density and volume. We further hypothesize that TH is critical for the timing and fidelity of skeletogenesis. In hormone-dysregulated fish, we found that massive bone and cartilage exostoses grow on the dentary. Thyroid hormone’s effects are highly bone-specific: in TH- fish, we see reduced density in many craniofacial bones, but also increased volume and mineralization in other regions of the dentary. These data suggest that TH plays a critical role in coordinating bone mineralization with growth
Thesis (MS) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Biology
He, Bihui. "Functional role of CKIP-1 for bone formation reduction during aging: micro CT analysis". HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/141.
Pełny tekst źródłaEpshteyn, Leonid. "OPTIMAL SPECIFICATIONS FOR MEASURING BONE-TO-IMPLANT CONTACT OF MINI-SCREWS USING MICRO-CT". Master's thesis, Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/395373.
Pełny tekst źródłaM.S.
The use of mini-screws (MSs) as temporary anchorage devices (TADs) is becoming more common in orthodontic treatment. With the increased use of TADs and the numerous manufactures producing them, research is needed to aid orthodontists in their selection of MSs. One of the major advantages of using mini-screw implants is that they can be loaded immediately and do not require osseoitegration.1 For this to be successful, the mini-screw needs to have adequate primary stability to retain itself in the bone. The mini-screw bone system relies on the stability of the mini-screw, the stability of the bone, and the stability of their interface.19,20 In the literature, this stability if usually quantified by measuring the pullout force, insertion torque and bone-to-implant contact.25,26 To date, much of the research has demonstrated that the geometric configuration of the mini-screw plays a significant role in its primary stability. Features such as pitch (length between threads), thread body design, screw length and diameter factor into primary stability.5,21,23 In order to observe the bone-to-implant contact traditionally, researchers had to perform histologic section. This method is destructive to the sample and does not allow it to be used for other analyses such as pullout force. With micro-CT technology, it is now possible to study the bone-to-implant relationship without destroying the sample and with great accuracy.6 Currently, it is unclear as to the optimal scanning specification to choose when using a micro-CT to measure bone-to-implant contact. The optimal scan is one, which provides the most accurate measurement within the least amount of time. The highest quality scans increase both time and costs of acquisition, while lower quality scans have the potential of introducing inaccuracies. This study aims to determine the optimal specifications needed to scan a mini-screw in bone using a SkyScan 1172 micro-CT, to measure the bone-to-implant contact. A total of three orthodontic mini-screws from Aarhus (American Orthodontics, Sheboygan, Wisc), 1.4 mm in diameter and 8 mm long were inserted into an adult pig mandible. All three mini-screws were inserted into the lingual area in the molar region. Each mini-screw was inserted until all the threads were buried into the bone. After placement, the blocks of bone containing the individual mini-screw were cut out and shaped to facilitate scanning by micro-CT. Each sample was be positioned and scanned individually using micro-CT (SkyScan 1172; SkyScan, Aartselaar, Belgium) under 5 different specifications, see table 1. SkyScan software was used to process the scans and calculate qualitative and quantitative data. For each sample bone-to-implant contact was measured. The software measured the TS, which is the area of the mini-screws surface and the IS, which is where the bone interfaces with the mini-screws. The IS/TSx100 was determined to be the percentage of the mini-screws surface that is in contact with bone or the bone-to-implant contact. Qualitative and quantitative analyses were performed to determine statically significant differences between the various bone-to-implant contact measurements of the samples. BIC varied greatly between the scanning specifications and samples, from 0% to 70.35%. Quantitative and qualitative analysis was performed to compare the differences in BIC(%) values between the 5 specifications. Two of the three samples displayed an accuracy of greater than 95% for specification 3, thus providing latitude in adjustment/reduction of scanning times with minimal variance in data accuracy for BIC(%). The results show for measuring BIC(%), scanning specifications can be modified/optimized to reduce scanning time while maintaining acceptable accuracy when scanning of large sample sizes are needed. It is recommended that for studies where absolute BIC(%) is needed, specification 5 is recommended since it will provide the most accurate measurement. For studies that are comparing changes in BIC(%), specification 3 is recommended as it will provide an acceptable level of accuracy in a reasonable amount time. However, due to limited sample size, more data is needed.
Temple University--Theses
Mohapatra, Sucheta. "Development and quantitative assessment of a beam hardening correction model for preclinical micro-CT". Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/3500.
Pełny tekst źródłaIori, Gianluca. "Micro-FEM models based on micro-CT reconstructions for the in vitro characterization of the elastic properties of trabecular bone tissue". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5422/.
Pełny tekst źródłaKlinge, Christine [Verfasser]. "Quantitative Strukturanalyse der Mäuselunge mit stereologischen Methoden: Korrelation von Micro-CT und Histologie / Christine Klinge". Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1037834569/34.
Pełny tekst źródłaTerrin, Massimo. "Micro-CT for small animal imaging : Optimization of the tube voltage for low-contrast imaging". Thesis, KTH, Skolan för teknik och hälsa (STH), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176482.
Pełny tekst źródłaMöllmann, Henriette Louise [Verfasser]. "Evaluation der Knochenarchitektur im diät-induzierten Osteoporosemodell der Ratte mittels Micro-CT / Henriette Louise Möllmann". Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1092995846/34.
Pełny tekst źródłaAndersson, Sebastian. "Implementation of a reconstruction software and image quality assessment tool for a micro-CT system". Thesis, KTH, Fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183147.
Pełny tekst źródłaYeslam, Hanin E. "The effect of acid etching on remineralization of incipient caries lesions : a micro-ct study /". Connect to resource online, 2009. http://hdl.handle.net/1805/2084.
Pełny tekst źródłaTitle from PDF t. p. (viewed Feb. 10, 2010) Advisor(s): Masatoshi Ando, Chair of the Research Committee, Carlos Gonzalez-Cabezas, Melvin Lund, Tien-Min Gabriel Chu, Michael Cochran. Curriculum vitae. Includes abstract. Includes bibliographical references (leaves 64-70).
Bianculli, Antonella. "Analysis of the scale effect in different computed tomography systems on the evaluation of bone tissue parameters". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11207/.
Pełny tekst źródłaLi, Yufei. "Joint super-resolution/segmentation approaches for the tomographic images analysis of the bone micro-structure". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI125/document.
Pełny tekst źródłaOsteoporosis is a disease characterized by loss of bone mass and degradation of bone microarchitecture. Although osteoporosis is not a fatal disease, the fractures it causes can lead to serious complications (damage to vessels and nerves, infections, stiffness), sometimes accompanied with risk of death. The bone micro-architecture plays an important role for the diagnosis of osteoporosis. Two common CT devices to scan bone micro architecture is High resolution-peripheral Quantitative CT and Micro CT. The former device gives access to in vivo investigation, but its spatial resolution is inferior. Micro CT gives better spatial resolution, but it is constrained to ex vivo measurement. In this thesis, we attempt to improve the spatial resolution of high resolution peripheral CT images so that the quantitative analysis of the resolved images is close to the one given by Micro CT images. We started from the total variation regularization, to a combination of total variation and double-well potential to enhance the contrast of results. Then we consider to use dictionary learning method to recover more structure details. Afterward, a deep learning method has been proposed to solve a joint super resolution and segmentation problem. The results show that the deep learning method is very promising for future applications
Barbar, Joseph Salem. "Influência do teor de ar incorporado no desempenho de concretos com diferentes teores de agregados". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/102/102131/tde-23012017-100027/.
Pełny tekst źródłaThe use of entraining air additives in concrete is a common practice in construction and its application influences several concrete properties in the fresh and hardened state. The aim of this study was evaluate the influence of air entrained content, by additive, in concrete performance with different aggregate contents. The experimental program included the evaluation of additives effectiveness of air entrainment in cement pastes, microstructural analysis and the concretes physical and mechanical properties and durability, with different levels of entrained air and aggregates. Tests were performed in fresh to determine the air content, density and slump. In hardened concrete, density, absorption, compressive strength, elastic modulus, ultrasonic pulse velocity, accelerated carbonation and thermal conductivity tests were performed. By computed X-ray microtomography, the pores present in the concrete samples were sized and quantified and determined the concretes porosities. The air entrained concrete presented decrease in mechanical strength. Concretes with lower aggregate levels presented lower mechanical strength, carbonation speed and thermal conductivity. According to the results, it can be concluded that the synthetic resins base additive was more efficient in air entrainment; larger air content implies variability in the results of the compressive strength and elastic modulus tests; concrete with higher aggregate levels presented higher carbonation speed, for the same entrained air content; thermal conductivity is inversely proportional to the air entrained content in concrete, and as lower was the aggregate content, lower was the thermal conductivity; the increase of air content in concrete promotes increase in the pores diameter and reduction of the incidence of spherical pores.
Bouhnaida, Zaïnaba. "Étude comparative de trois systèmes de préparation canalaire en endodontie : Étude in vitro en micro-CT". Thesis, Reims, 2018. http://www.theses.fr/2018REIMO201/document.
Pełny tekst źródłaThe aim of this study is to compare the respect of the root canal morphology after instrumentation with different shaping systems (One Shape NEW Generation®, Wave One® and Revo-S®), by using Micro-Computed Tomography.We used a fully three-dimensional (3D) methodological process which involved the reconstruction, registration and segmentation. By this methodological process, images have been acquired and processed in order to extract registered canals images before and after the instrumentation. The segmentation artifacts like calcifications and debris have been taken into account. A method to estimate the non-instrumented zones is also described.The canal transportation was calculated for each slice of each root-third by comparing the position of the centroids before and after instrumentation. No significant difference was found between the three instrumentation systems when canal transport means were done.This 4-part methodological approach has enabled the validation of a reproducible 3D imaging protocol. This can be applied in vitro in endodontic research for analysis of the instrumental effects
Shkarin, Roman [Verfasser]. "Machine learning-based automated segmentation with a feedback loop for 3D synchrotron micro-CT / Roman Shkarin". Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1228439400/34.
Pełny tekst źródłaLemmon, Heber. "Methods for reduced platen compression (RPC) test specimen cutting locations using micro-CT and planar radiographs". Texas A&M University, 2003. http://hdl.handle.net/1969/310.
Pełny tekst źródłaTuchman, Marni. "COMPARISON OF INSERTION ANGULATIONS MEASURED VIA BONE-TO-IMPLANT CONTACT OF MINI-SCREWS USING MICRO-CT". Master's thesis, Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/520294.
Pełny tekst źródłaM.S.
Bone-to-implant contact of orthodontic mini-screws has been determined via Micro-CT to be a strong predictor of primary stability. Various insertion angulations, including both 900 and 500, have been reported as ideal for providing optimum primary stability. The aim of this investigation was to determine if a statistically significant difference exists in the bone-to-implant contact of mini-screws placed with an insertion angulation of 900 compared to those placed at 500 as determined via Micro-CT. Ten self-drilling, self-tapping orthodontic mini-screws (Aarhus,1.5mmx6mm) (n=5) were inserted into the posterior ramus of an adult pig mandible, an analog to an adult human mandible. A custom stent with ten holes, five at 900 and five at 500, was fitted to the bone surface to control insertion angulation. The bone was cut to 1.5x1.5x1cm segments and scanned using SkyScan 1127 with ideal specifications (8mm pixel size, medium camera, 80Kv, 100mA, 10W, 1800 rotation, and 0.5Al+0.25Cu filter). The raw scans were reconstructed using NReconV1.6.10 and these datasets were then reoriented using DataviewerV1.5.2 along the Z-axis to standardize the peri-implant bone for analysis. A custom task-list was used with CT-AnalyzerV1.14.41 to determine the percent of bone-to-implant contact per mini-screw. A Mann-Whitney U test indicated that the bone-to-implant contact was not statistically significantly different for the mini-screws placed at 900 (Mdn= 72.34) compared to the mini-screws placed at 500 (Mdn= 53.25), U=5, p=.1443. Therefore, the results do not significantly differ at p<.05. There is no statistically significant difference in the bone-to-implant contact between the Aarhus 1.5mmx6mm orthodontic mini-screws placed at 900 compared to those placed at 500 as measured by Micro-CT. This may lead to the conclusion that there is no significant difference in the primary stability of Aarhus mini-screws placed at 900 and 500.
Temple University--Theses
Dong, Pei. "Three-dimensional analysis of bone cellular tissue from SR CT Imaging". Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0022/document.
Pełny tekst źródłaThe osteocyte system has raised increasing interest in the recent years, since it is hypothesized to play an important role in orchestrating bone adaptation through mechanosensation and bone mechanotransduction mechanism. The osteocytes are deeply buried within the bone matrix, where their bodies are encysted in cavities called lacunae and their stellular processes are enclosed in tunnels called canaliculi. Together, they formed the lacuno-canalicular network (LCN). The geometry of the LCN is of importance since it is supposed to potentially affect and reflect the viability of the osteocyte and is supposed to be related to biomechanical constraints at the cell level. However, studying the LCN is quite challenging, due to limitations in an ideal imaging modality and the lack of quantitative analysis tools. In this thesis, we propose computational efficient and automated methods to quantify the 3D morphological properties of the LCN from synchrotron radiation (SR) micro / nano-CT images. For image acquisition, we used the SR micro/nano-CT setups installed on beamlines ID19 and ID22 at ESRF. A series of human cortical samples were imaged with spatial resolutions ranging between 3.5 µm to 60 nm. For the 3D assessment of lacunae, we used an image moment-based approach to calculate the volume, length, width, height and anisotropy of each osteocyte lacuna. We employed a fast algorithm to further calculate the surface area, the Euler number and the SMI of each lacuna. Validation of segmentation and experimental results on 13 bone samples are presented. For the 3D assessment of canaliculi, we propose a method to quantify the canalicular ramification around each lacuna. After segmentation, our method first labels each lacuna from the LCN. Then, a signature of the numbers of canaliculi at different distances from the lacunar surface is estimated through the calculation of topological parameters. Validation of this method and statistical results a large 3D SR micro-CT image of a human femoral bone sample are reported. We also improved the segmentation of the canaliculi and illustrated the feasibility of the application on a series of bone samples. We investigated a segmentation approach based on minimum cost paths and geodesic voting. A parallel computation scheme was implemented to reduce the computation times. The LCN was characterized by using the previous methods. Besides, we introduced the parameters from the Voronoi tessellation. Statistical results are reported on 8 large 3D micro-CT images, including around a hundred lacunae and the canaliculi. Future works will concern the improvement of canaliculi segmentation of from images at 300 nm as well as its evaluation and further characterization of LCN from SR CT images at both 300 nm and 50 nm. This work opens many perspectives for a better knowledge of the physiopathology of bone at the cellular scale