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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efetividade da fluorescência a laser no diagnóstico de lesões de cárie. Estudos in vitro e in vivo

Diniz, Michele Baffi [UNESP] January 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2006Bitstream added on 2014-06-13T18:31:58Z : No. of bitstreams: 1 diniz_mb_me_arafo.pdf: 3188878 bytes, checksum: afb48495eaac71c8663023ac0c8eba58 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente estudo foi avaliar a efetividade da fluorescência a laser (KaVo DIAGNOdent) para a determinação da severidade de lesões de cárie oclusal em dentes permanentes in vivo e para determinação da remineralização in vitro de lesões de cárie induzidas artificialmente em esmalte de dentes bovinos. No estudo in vitro, 78 blocos de esmalte com lesões de cárie artificial (mancha branca) com valores de dureza Vickers de 38,48 l 0,85 foram submetidos ao tratamento com dentifrício fluoretado durante a ciclagem de pH, para promover a remineralização. Antes do início do experimento, após a desmineralização e após a remineralização foram realizadas análises com a fluorescência a laser e análises de microdureza superficial do esmalte. Foram encontradas diferenças significantes nas medidas de microdureza superficial (p < 0,0001) nas 3 etapas. Os valores encontrados nas leituras com a fluorescência a laser foram extremamente baixos (entre 0-5), apresentando diferença estaticamente significante somente após a remineralização. No estudo in vivo, foram selecionados 130 sítios de primeiros molares permanentes hígidos ou com presença de lesões de cárie incipientes na superfície oclusal, em crianças com idade entre 7 a 12 anos. Após profilaxia, foi realizada a inspeção visual pelo Examinador A e 23 o exame com o DIAGNOdent pelo Examinador B. Apenas os sítios com sinais sugerindo lesão de cárie foram abertos com equipamentos que permitiram preparos conservadores e a extensão da lesão (padrão-ouro) foi determinada pelo Examinador C. De acordo com os pontos de corte propostos pela KaVo (1999) e com os novos pontos de corte estabelecidos pela curva ROC, observamos uma diferença na especificidade, 0,31 e 0,85 respectivamente, considerando todas as lesões como cariadas, e um equilíbrio entre sensibilidade.... / The purpose of this study was to evaluate the effectiveness of laser fluorescence device (DIAGNOdent) in detecting in vivo depth of occlusal caries lesions in permanent teeth and detecting in vitro remineralization of artificial caries lesions in enamel bovine teeth. On in vitro study, 78 enamel blocks with artificial caries lesions (white spot lesions) with Vickers microhardness number of 38.48 l 0.85 were submitted to dentifrice treatment during the pH-cycling, to promote remineralization. At baseline, after demineralization and after remineralization analyses were carried through with laser fluorescence device and enamel superficial microhardness analyses. Significant differences in superficial microhardness measures were found in the 3 stages (p < 0.0001). Values found in laser fluorescence readings were extremely low (between 0-5), presenting difference statistically significant only after remineralization. On in vivo study, one hundred and third sites from occlusal surfaces of sound or carious first permanent molars were selected in children, aged between 7 and 12 years. After professional cleaning, visual inspection was performed by Examiner A and laser fluorescence (DIAGNOdent) assessment by Examiner B. Only the sites presenting signals suggesting caries lesions were opened that resulted from minimal intervention and the 26 lesion extension (gold-standard) was determined by Examiner C. In accordance with cut-off points proposed by KaVo (1999) and with the new cut-off points established by ROC curves, we observe a difference in specificity, 0.31 and 0.85 respectively, considering all lesions as caries, and a balance between sensitivity (0.70) and specificity (0.87) for the new cut-off points considering dentine lesions only. Accuracy for visual inspection was ...(Complete abstract, click electronic address below).
2

Efetividade da fluorescência a laser no diagnóstico de lesões de cárie. Estudos in vitro e in vivo /

Diniz, Michele Baffi. January 2006 (has links)
Orientador: Rita de Cássia Loiola Cordeiro / Banca: Fausto Medeires Mendes / Banca: Lourdes Aparecida Martins dos Santos Pinto / Resumo: O objetivo do presente estudo foi avaliar a efetividade da fluorescência a laser (KaVo DIAGNOdent) para a determinação da severidade de lesões de cárie oclusal em dentes permanentes in vivo e para determinação da remineralização in vitro de lesões de cárie induzidas artificialmente em esmalte de dentes bovinos. No estudo in vitro, 78 blocos de esmalte com lesões de cárie artificial (mancha branca) com valores de dureza Vickers de 38,48 l 0,85 foram submetidos ao tratamento com dentifrício fluoretado durante a ciclagem de pH, para promover a remineralização. Antes do início do experimento, após a desmineralização e após a remineralização foram realizadas análises com a fluorescência a laser e análises de microdureza superficial do esmalte. Foram encontradas diferenças significantes nas medidas de microdureza superficial (p < 0,0001) nas 3 etapas. Os valores encontrados nas leituras com a fluorescência a laser foram extremamente baixos (entre 0-5), apresentando diferença estaticamente significante somente após a remineralização. No estudo in vivo, foram selecionados 130 sítios de primeiros molares permanentes hígidos ou com presença de lesões de cárie incipientes na superfície oclusal, em crianças com idade entre 7 a 12 anos. Após profilaxia, foi realizada a inspeção visual pelo Examinador A e 23 o exame com o DIAGNOdent pelo Examinador B. Apenas os sítios com sinais sugerindo lesão de cárie foram abertos com equipamentos que permitiram preparos conservadores e a extensão da lesão (padrão-ouro) foi determinada pelo Examinador C. De acordo com os pontos de corte propostos pela KaVo (1999) e com os novos pontos de corte estabelecidos pela curva ROC, observamos uma diferença na especificidade, 0,31 e 0,85 respectivamente, considerando todas as lesões como cariadas, e um equilíbrio entre sensibilidade ...(Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The purpose of this study was to evaluate the effectiveness of laser fluorescence device (DIAGNOdent) in detecting in vivo depth of occlusal caries lesions in permanent teeth and detecting in vitro remineralization of artificial caries lesions in enamel bovine teeth. On in vitro study, 78 enamel blocks with artificial caries lesions (white spot lesions) with Vickers microhardness number of 38.48 l 0.85 were submitted to dentifrice treatment during the pH-cycling, to promote remineralization. At baseline, after demineralization and after remineralization analyses were carried through with laser fluorescence device and enamel superficial microhardness analyses. Significant differences in superficial microhardness measures were found in the 3 stages (p < 0.0001). Values found in laser fluorescence readings were extremely low (between 0-5), presenting difference statistically significant only after remineralization. On in vivo study, one hundred and third sites from occlusal surfaces of sound or carious first permanent molars were selected in children, aged between 7 and 12 years. After professional cleaning, visual inspection was performed by Examiner A and laser fluorescence (DIAGNOdent) assessment by Examiner B. Only the sites presenting signals suggesting caries lesions were opened that resulted from minimal intervention and the 26 lesion extension (gold-standard) was determined by Examiner C. In accordance with cut-off points proposed by KaVo (1999) and with the new cut-off points established by ROC curves, we observe a difference in specificity, 0.31 and 0.85 respectively, considering all lesions as caries, and a balance between sensitivity (0.70) and specificity (0.87) for the new cut-off points considering dentine lesions only. Accuracy for visual inspection was ...(Complete abstract, click electronic address below). / Mestre
3

Image Processing and Super Resolution Methods for a Linear 3D Range Image Scanning Device for Forensic Imaging

Joshi, Abhishek Shriram 14 August 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the last few decades, forensic science has played a significant role in bringing criminals to justice. Shoe and tire track impressions found at the crime scene are important pieces of evidence since the marks and cracks on them can be uniquely tied to a person or vehicle respectively. We have designed a device that can generate a highly accurate 3-Dimensional (3D) map of an impression without disturbing the evidence. The device uses lasers to detect the changes in depth and hence it is crucial to accurately detect the position of the laser. Typically, the forensic applications require very high resolution images in order to be useful in prosecutions of criminals. Limitations of the hardware technology have led to the use of signal and image processing methods to achieve high resolution images. Super Resolution is the process of generating higher resolution images from multiple low resolution images using knowledge about the motion and the properties of the imaging geometry. This thesis presents methods for developing some of the image processing components of the 3D impression scanning device. In particular, the thesis describes the following two components: (i) methods to detect the laser stripes projected onto the impression surface in order to calculate the deformations of the laser stripes due to 3D surface shape being scanned, and (ii) methods to improve the resolution of the digitized color image of the impression by utilizing multiple overlapping low resolution images captured during the scanning process and super resolution techniques.

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