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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.
51

Comparação do comprimento de trabalho do canal radicular usando tomografia computadorizada de feixe cônico, radiografia periapical e localizador apical eletrônico / In vivo comparison of root canal working length using cone beam computed tomography, periapical radiograph, and electronic apex locator

MORAIS, André Luiz Gomide de 13 February 2012 (has links)
Made available in DSpace on 2014-07-29T15:21:58Z (GMT). No. of bitstreams: 1 Dissertacao Andre Luiz Gomide de Morais.pdf: 1627953 bytes, checksum: 05ab427707618c3afdeb890e320268e6 (MD5) Previous issue date: 2012-02-13 / Introduction Strategies to obtain the working length to prepare and fill the root canals has been relevant theme of discussion in endodontics. The purpose of this study was to compare in vivo the canal root working length measures determined by cone beam computed tomography (CBCT) images with the ones obtained by using periapical radiograph and electronic apex locator. Methods The root canal working lengths of 30 single-rooted teeth from 19 patients whose diagnosis was apical periodontitis were evaluated. Initial periapical radiographs for diagnosis and treatment planning, employing the parallelism technique, were taken. CBCT images were acquired with i-CAT system (aiming of diagnosing the cases of apical periodontitis that showed to be complex and doubtful) and measured with specific function of i-CAT software. The coronal opening was made, the root canals were irrigated with sodium hypochlorite solution 2.5%, being performed the exploration and initial emptying of root canal. After, the preparation of the inlet orifice and of the cervical root third was carried out . The minor foramen was located using Root ZX® locator by advancing a stainless steel K-file that best suited the root canal, according to the manufacturer´s instructions. The radiographic measurement was made by advancing a stainless steel K-file in the root canal, until its tip was 1.0 mm from the root apex (determined from the measures obtained by the electronic ape locator). These 3 working length were tabulated and compared. Kruskal-Wallis test was used to analyze the differences between working lengths methods. The significance was set at α=5%. Results The mean values and standard deviations for working length determination by electronic apex locator, periapical radiograph and CBCT images were 21.5 ± 3.1, 21.32 ± 3, 21.4 ± 2.7, respectively. Significant differences were not verified statistically (P>0.05). Conclusions CBCT images working length determination showed to be as similar as the determinations obtained by using periapical radiograph and electronic apex locator. / Introdução: Estratégias para obtenção do comprimento de trabalho para preparar e obturar canais radiculares têm sido tema relevante de discussão em Endodontia. O objetivo deste estudo foi comparar in vivo as medidas de comprimento de trabalho do canal radicular determinadas por meio da tomografia computadorizada de feixe cônico (TCFC) com as obtidas por meio de radiografia periapical e localizador apical eletrônico. Metodologia: Foram avaliados os comprimentos de trabalho dos canais radiculares em 30 dentes de 19 pacientes com diagnóstico de periodontite apical. Radiografias periapicais iniciais de diagnóstico e plano de tratamento, empregando a técnica do paralelismo, foram realizadas. As imagens de TCFC foram obtidas usando o sistema i-CAT (com o intuito de diagnosticar os casos de periodontite apical que se mostraram complexos ou duvidosos) e foram medidas a partir de função específica do programa desse sistema. Foi realizada a abertura coronária, os canais radiculares foram irrigados solução de hipoclorito de sódio a 2,5%, sendo realizada a exploração e o esvaziamento inicial do canal radicular. Depois foi realizado o preparo do orifício de entrada e do terço cervical da raiz. O forame apical foi localizado usando o localizador Root ZX® por meio do avanço de uma lima tipo K-file que melhor se adaptasse ao canal radicular de aço inoxidável no canal radicular, de acordo com instruções do fabricante. A medida radiográfica foi feita por meio da colocação de uma lima tipo K-file de aço inoxidável no canal radicular, até que sua ponta estivesse a 1,0mm do ápice radicular (determinado pelas medidas obtidas com o localizador apical eletrônico). Essas três medidas de comprimento de trabalho foram tabuladas e comparadas. O teste de Kruskal-Wallis foi empregado para analisar as diferenças entre os métodos de obtenção dos comprimentos de trabalho. O nível de significância foi estabelecido em α=5%. Resultados: O valor médio e os desvios-padrões para a determinação do comprimento de trabalho por meio de imagens de TCFC, localizador apical eletrônico e radiografia periapical foram de e 21,4 ± 2,7, 21,5 ± 3,1, 21,32 ± 3, respectivamente. Diferenças significantes entre as medidas obtidas pelos três métodos não foram verificadas (p>0.05). Conclusões: A determinação do comprimento de trabalho em imagens de TCFC mostrou ser tão similar quanto às determinações obtidas por meio do método radiográfico e do localizador apical eletrônico.
52

Evaluating Artificial Intelligence in Dental Radiography / Utvärdering av artificiell intelligens inom tandradiografi

Baza, Rabi January 2024 (has links)
The integration of Artificial Intelligence (AI) in dental radiography not only presents an opportunity but also holds immense potential to enhance diagnostic accuracy and efficiency. This study addresses the exciting challenge of leveraging AI, specifically a generative pre-trained transformer model, to interpret dental panoramic X-rays, a task traditionally reliant on human expertise. The central purpose of the study is to evaluate the diagnostic capabilities of this AI model compared to professional dental evaluations, focusing on its accuracy and consistency, thereby paving the way for a promising future in dental diagnostics. The research involved a sample of 35 dental panoramic X-rays obtained from Flexident AB, anonymized and annotated by a panel of dental professionals. The study was conducted in two stages: Stage One tested the AI model in three different methods: 1- without any annotations, 2- with numbered teeth, and 3- with colored circles highlighting areas of interest. Stage Two involved training a specialized GPT model with domain-specific knowledge. Key findings indicate that the AI model, when provided with detailed visual annotations, achieved diagnostic accuracy comparable to that of dental professionals, as statistical analysis showed no significant differences between the golden standard (dentist group) and the visually annotated group (P>0.05). However, the model struggled with unannotated images, highlighting the importance of structured input. The research underscores the potential of language-based AI in medical imaging while emphasizing the need for detailed input to optimize performance. This study is pioneering in applying a generative pre-trained transformer model for dental diagnostics, opening new avenues for AI integration in healthcare. / Integrationen av artificiell intelligens (AI) inom tandradiografi innebär inte bara en möjlighet utan har också en enorm potential att förbättra diagnostisk noggrannhet och effektivitet. Denna studie tar upp den spännande utmaningen att utnyttja AI, specifikt en generativ förtränad transformer-modell, för att tolka panoramaröntgenbilder av tänder, en uppgift som traditionellt är beroende av mänsklig expertis. Studiens centrala syfte är att utvärdera de diagnostiska förmågorna hos denna AI-modell jämfört med professionella tandläkarbedömningar, med fokus på dess noggrannhet och konsekvens, vilket banar väg för en lovande framtid inom tanddiagnostik. Forskningen omfattade ett urval av 35 panoramaröntgenbilder av tänder erhållna från Flexident AB, anonymiserade och annoterade av en panel av tandläkare. Studien genomfördes i två steg: Steg ett testade AI-modellen på tre olika sätt: 1- utan några annoteringar, 2- med numrerade tänder och 3- med färgade cirklar som markerade intressanta områden. Steg två involverade träning av en specialiserad GPT-modell med domänspecifik kunskap. Nyckelresultat visar att AI-modellen, när den tillhandahölls detaljerade visuella annotationer, uppnådde en diagnostisk noggrannhet jämförbar med professionella tandläkare, då statistisk analys visade inga signifikanta skillnader mellan guldstandarden (tandläkargruppen) och den visuellt annoterade gruppen (P>0,05). Modellen hade dock svårigheter med icke-annoterade bilder, vilket understryker vikten av strukturerad inmatning. Forskningen betonar potentialen hos språkbaserad AI inom medicinsk avbildning och behovet av detaljerad inmatning för att optimera prestanda. Denna studie är banbrytande i sin tillämpning av en generativ förtränad transformer-modell för tanddiagnostik, vilket öppnar nya möjligheter för AI-integrering inom sjukvården.

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