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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

Influência de diferentes meios de digitalização de radiografias na avalição de cáries proximais / Comparative performance of indirect digitized radiographs for detecting approximal caries

Xavier, Claudio Roberto Gaião 26 October 2007 (has links)
Avaliar a influência no diagnóstico de cáries proximais das imagens geradas por dois escâneres e quatro máquinas fotográficas digitais, em formato JPEG e TIFF, e comparar o desempenho destes equipamentos ao das radiografias convencionais em relação à presença e profundidade de lesões de cárie proximais. 56 dentes extraídos foram radiografados com filme Kodak Insight em um aparelho de raios X Yoshida Kaycor, operando com 70kv e 7mA, com tempo de exposição de 0,40s. As radiografias resultantes foram digitalizadas pelos escaneres CanonScan e Genius ColorPage, e máquinas fotográficas digitais Canon Powershot G2, Canon RebelXT, Nikon Coolpix 8700 e Nikon D70s, nos formatos JPEG e TIFF. As radiografias convencionais e as imagens digitais obtidas foram avaliadas por três examinadores em duas sessões de observação. Classificaram a presença de acordo com uma escala de três níveis e a profundidade de acordo com uma escala de três níveis, quando julgassem que havia lesão. Os dentes foram seccionados no sentido mésiodistal e observados ao microscópio em luz polarizada com aumento de 10x, para a verificação da presença e profundidade da lesão de cárie. Foram determinados concordância intra e interexaminadores, probabilidade de não diagnóstico, sensibilidade, especificidade e acurácia para cada equipamento, em ambos os formatos, e para as radiografias convencionais. Os resultados foram submetidos à análise de variância a dois critérios, demonstrando que não houve diferenças estatisticamente significantes entre os formatos. A concordância intraexaminadores foi de moderada a satisfatória, e a interexaminadores de regular a moderada. A probabilidade de não diagnóstico variou de 1,34% (Convencional) a 52,83% (Escaner CanonScan/JPEG). A sensibilidade variou de 0,24 (Canon RebelXT/JPEG) a 0,53 (Convencional), a especificidade de 0,93 (Nikon Coolpix/JPEG; Canon Powershot/TIFF; Cânon RebelXT/JPEG e TIFF) a 0,97 (Escaner CanonScan/TIFF e JPEG), e a acurácia variou de 0,82 (Canon RebelXT/JPEG) a 0,91 (Escaner CanonScan/JPEG). O teste de proporções indicou diferenças estatisticamente significantes para o Escaner CanonScan, para ambos os formatos, quando comparado aos demais equipamentos e à radiografia convencional. Foi possível concluir que os formatos não influenciaram o desempenho no diagnóstico de cárie para qualquer equipamento usado. O Escaner CanonScan apresentou o pior desempenho e não se mostrou adequado para digitalização de radiografias para o diagnóstico de lesões de cárie. / To evaluate the performance of conventional and indirect digital radiography and the effect of JPEG and TIFF file formats for detecting proximal surface caries. Fifty-six extracted teeth were mounted in blocks and radiographed with Insight conventional film. Films were digitized by two flatbed scanners (Canon CanonScan and Genius ColorScan) and four digital cameras (Canon Powershot G2, Canon Rebel XT, Nikon Coolpix 8700 and Nikon D70), in both JPEG and TIFF file formats. Three observers recorded the presence and depth of caries on 112 proximal surfaces for the conventional and digitized radiographs. They scored lesion presence in a 3-point confidence scale and depth on another 3-point scale. Radiographs were evaluated twice. The observer\'s scores were compared with the results from a histological examination. Intra-observer agreement was moderate to good and interobserver agreement was fair to moderate. Sensitivities varied from 0.24 (Canon RebelXT/JPEG) to 0.53 (Convencional) and specificities from 0.93 (Nikon Coolpix/JPEG; Canon Powershot/TIFF; Canon RebelXT/JPEG e TIFF) to 0.97 (Escaner CanonScan/TIFF e JPEG). The accuracy varied from 0.82 (Canon RebelXT/JPEG) to 0.91 (Escaner CanonScan/JPEG). Images from CanonScan, both JPEG and TIFF, showed significant statistically differences compared with digital radiographs from the others devices and conventional film radiographs. File formats did not influences the detection of proximal caries. Digitizing conventional radiographs using the scanner CanonScan did not produce images of diagnostic quality.
2

Influência de diferentes meios de digitalização de radiografias na avalição de cáries proximais / Comparative performance of indirect digitized radiographs for detecting approximal caries

Claudio Roberto Gaião Xavier 26 October 2007 (has links)
Avaliar a influência no diagnóstico de cáries proximais das imagens geradas por dois escâneres e quatro máquinas fotográficas digitais, em formato JPEG e TIFF, e comparar o desempenho destes equipamentos ao das radiografias convencionais em relação à presença e profundidade de lesões de cárie proximais. 56 dentes extraídos foram radiografados com filme Kodak Insight em um aparelho de raios X Yoshida Kaycor, operando com 70kv e 7mA, com tempo de exposição de 0,40s. As radiografias resultantes foram digitalizadas pelos escaneres CanonScan e Genius ColorPage, e máquinas fotográficas digitais Canon Powershot G2, Canon RebelXT, Nikon Coolpix 8700 e Nikon D70s, nos formatos JPEG e TIFF. As radiografias convencionais e as imagens digitais obtidas foram avaliadas por três examinadores em duas sessões de observação. Classificaram a presença de acordo com uma escala de três níveis e a profundidade de acordo com uma escala de três níveis, quando julgassem que havia lesão. Os dentes foram seccionados no sentido mésiodistal e observados ao microscópio em luz polarizada com aumento de 10x, para a verificação da presença e profundidade da lesão de cárie. Foram determinados concordância intra e interexaminadores, probabilidade de não diagnóstico, sensibilidade, especificidade e acurácia para cada equipamento, em ambos os formatos, e para as radiografias convencionais. Os resultados foram submetidos à análise de variância a dois critérios, demonstrando que não houve diferenças estatisticamente significantes entre os formatos. A concordância intraexaminadores foi de moderada a satisfatória, e a interexaminadores de regular a moderada. A probabilidade de não diagnóstico variou de 1,34% (Convencional) a 52,83% (Escaner CanonScan/JPEG). A sensibilidade variou de 0,24 (Canon RebelXT/JPEG) a 0,53 (Convencional), a especificidade de 0,93 (Nikon Coolpix/JPEG; Canon Powershot/TIFF; Cânon RebelXT/JPEG e TIFF) a 0,97 (Escaner CanonScan/TIFF e JPEG), e a acurácia variou de 0,82 (Canon RebelXT/JPEG) a 0,91 (Escaner CanonScan/JPEG). O teste de proporções indicou diferenças estatisticamente significantes para o Escaner CanonScan, para ambos os formatos, quando comparado aos demais equipamentos e à radiografia convencional. Foi possível concluir que os formatos não influenciaram o desempenho no diagnóstico de cárie para qualquer equipamento usado. O Escaner CanonScan apresentou o pior desempenho e não se mostrou adequado para digitalização de radiografias para o diagnóstico de lesões de cárie. / To evaluate the performance of conventional and indirect digital radiography and the effect of JPEG and TIFF file formats for detecting proximal surface caries. Fifty-six extracted teeth were mounted in blocks and radiographed with Insight conventional film. Films were digitized by two flatbed scanners (Canon CanonScan and Genius ColorScan) and four digital cameras (Canon Powershot G2, Canon Rebel XT, Nikon Coolpix 8700 and Nikon D70), in both JPEG and TIFF file formats. Three observers recorded the presence and depth of caries on 112 proximal surfaces for the conventional and digitized radiographs. They scored lesion presence in a 3-point confidence scale and depth on another 3-point scale. Radiographs were evaluated twice. The observer\'s scores were compared with the results from a histological examination. Intra-observer agreement was moderate to good and interobserver agreement was fair to moderate. Sensitivities varied from 0.24 (Canon RebelXT/JPEG) to 0.53 (Convencional) and specificities from 0.93 (Nikon Coolpix/JPEG; Canon Powershot/TIFF; Canon RebelXT/JPEG e TIFF) to 0.97 (Escaner CanonScan/TIFF e JPEG). The accuracy varied from 0.82 (Canon RebelXT/JPEG) to 0.91 (Escaner CanonScan/JPEG). Images from CanonScan, both JPEG and TIFF, showed significant statistically differences compared with digital radiographs from the others devices and conventional film radiographs. File formats did not influences the detection of proximal caries. Digitizing conventional radiographs using the scanner CanonScan did not produce images of diagnostic quality.
3

Ability of 5th year Students to Detect Early Interproximal Caries

Muzan, Abdalla January 2021 (has links)
Magister Scientiae Dentium - MSc(Dent) / Objective: The objectives of this study were to evaluate the diagnostic capability of 5th year students using digital imaging, conventional bitewing radiographs (BW), printed film on paper and to compare the results with the observers’ experience level to detect early interproximal caries lesions on radiographs. To map the literature in regards to different diagnostic methods that students use globally in dental clinics by conducting a scoping review. Methods: A cross-sectional study was conducted with senior dental students (Reg No: BM 19/9/8). Three digital radiographs were shown individually to the students on a screen, 3 bitewing radiographs and 3 printed films on paper were passed on individually to all students with a questionnaire; with a viewing time of 2 mins per radiograph; thus 9 radiographs in total were viewed. A control group consisting of specialists from both the Restorative and Radiology Departments had finalized the answers prior to conducting the study regarding the presence/absence of caries and its depth on all 3 different radiographic images. The answers recorded by students were divided into 5 categories, R0: Intact surface, R1: Radiolucency in outer half of enamel, R2: Radiolucency in inner half of enamel, R3: Radiolucency in outer half of dentin, and R4: Radiolucency in inner half of dentin. A protocol specific for the objectives of this study was developed according to the criteria for a scoping reviews. Relevant databases (Pubmed, Scopus, Ebscohost, Science Direct, Wiley Online Library and Cochrane Library) were searched to identify evidence which was restricted to the English language for the period 2015–2021. Results: Comparison using an Anova test on the 3 different diagnostic methods showed that the type of method used affects the presence detection and size measuring accuracy, where the P-value confirms a significant difference. The Prisma flow diagram showed a result of the most common methods for diagnosing interproximal caries happen to be visual examination and bitewing radiography. Conclusions: Senior dental students have shown good accuracy in detecting the presence of interproximal caries. Although the accuracy in detecting the size of carious lesions was poor.
4

Performance of near infared digital imaging transillumination for detection of non-cavitated approximal caries

Abogazalah, Naif Nabel Fouad 01 June 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Objective: The objectives of this in-vitro study were: 1) to evaluate the ability of Near-Infrared Digital Imaging Transillumination (NIDIT) to detect non-cavitated approximal caries lesions; and 2) to compare the performance among NIDIT, Digital Radiography (DR), Digital Imaging Fiber-Optic Trans-Illumination (DIFOTI) and International Caries Detection and Assessment System (ICDAS). Methods: Thirty human extracted premolars were selected. The approximal surface status ranged from sound to surfaces with non-cavitated caries lesions into the outer one-third of the dentin. Lesion depth was determined by micro-computed tomography (μ-CT) and used as a gold standard. Teeth were mounted in a custom-made device to simulate approximal contact. ICDAS, DR, DIFOTI and NIDIT examinations were performed and repeated by three trained and calibrated examiners. Sensitivity, specificity, area under ROC curve (Az), inter- and intra-class correlation coefficients (ICCs) of each method, and correlation among the methods were determined. Results: ICCs for intra-/inter-examiner agreement were almost perfect for DIFOTI (0.85/0.83), substantial for ICDAS (0.79/0.72) and NIDIT (0.69/0.64), and moderate for DR (0.52/0.48). Sensitivity/specificity for DIFOTI, ICDAS, DR, and NIDIT were 0.91/0.69, 0.89/0.83, 0.50/0.64, and 0.68/0.93, respectively. Az of DR (0.61) was significantly lower than that of DIFOTI (0.91, p = 0.002) and ICDAS (0.90, p = 0.005), but was not significantly different from NIDIT (0.81, p = 0.052). DIFOTI, ICDAS, and NIDIT were not significantly different from each other (p > 0.13). Spearman correlation coefficients for DIFOTI (0.79, p < 0.001), ICDAS (0.74, p < 0.001), and NIDIT (0.65, p < 0.001) demonstrated a moderate association with μ-CT, while that of DR suggested no association (0.19, p = 0.289). Conclusion: Within the limitations of this in-vitro study, NIDIT system demonstrated a potential for early approximal caries detection. ICDAS, DIFOTI, and NIDIT were superior to DR in terms of validity and reliability.
5

Alveolar bone loss in radiographic modalities for diagnosis of periodontal disease / Periodonto ligų diagnozavimas: dantinės ataugos pokyčių analizė, taikant skirtingus rentgeninio tyrimo metodus

Ivanauskaitė, Deimantė 21 June 2011 (has links)
Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed. / Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti. Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti. Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas. Pagal šio tyrimo... [toliau žr. visą tekstą]
6

Periodonto ligų diagnozavimas: dantinės ataugos pokyčių analizė, taikant skirtingus rentgeninio tyrimo metodus / Alveolar bone loss in radiographic modalities for diagnosis of periodontal diseases

Ivanauskaitė, Deimantė 21 June 2011 (has links)
Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti. Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti. Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas. Pagal šio tyrimo... [toliau žr. visą tekstą] / Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed.

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