Esta pesquisa in vitro, avaliou comparativamente a acurácia do diagnóstico do método radiográfico digital com o método radiográfico convencional, na detecção de lesões de cárie oclusal em molares decíduos. O material foi composto por 55 dentes posteriores decíduos, que apresentavam pigmentações e pelo menos um sítio suspeito de lesão de cárie oclusal, sem restaurações e superfícies sem selantes. As radiografias digitais foram executadas com o sistema Dixi3 (Planmeca, Helsink, Finland) e as radiografias convencionais com o filme Insight (Kodak Eastman Co., EUA), ambas de modo padronizado, em idênticas condições geométricas. As imagens foram avaliadas individualmente por três radiologistas, em ideais condições de interpretação radiográfica e sem acesso aos recursos de manipulação de imagens do sistema digital. Os achados foram classificados de acordo com o seguinte critério: 0 - ausência de radiolucidez no esmalte, 1- radiolucidez confinada ao esmalte, 2- radiolucidez no esmalte até o limite dentina-esmalte, 3- radiolucidez no esmalte e na metade mais externa da dentina, 4- radiolucidez no esmalte alcançando a metade mais interna da dentina. O padrão ouro foi obtido pelo estudo histológico. Os dados foram analisados através do teste de Freidman (P <= 0,05). Os resultados obtidos com os filmes radiográficos convencionais foram similares aos resultados obtidos com as radiografias digitais diretas e o padrão ouro, porém os resultados obtidos com o sistema radiográfico digital foram significativamente menores que o histológico. Nas condições deste estudo, concluímos que o método de radiografia digital subestimou a extensão das lesões de cárie oclusal em molares decíduos. / This in vitro research, evaluated the accuracy of the direct digital radiographic method compared to the conventional radiographic method in the analysis of the extension of occlusal carious lesions in primary molars. The material was composed by 55 primary molars presenting pigmentation and, at least, one suspect site of occlusal carious lesion, these teeth had neither restoration nor surfaces with sealant. Digital radiographs were obtained with the Dixi3 system (Planmeca, Helsink, Finland) and the conventional radiographs with the Insight film (Kodak Eastman Co., USA), both in standard form and identical geometrical conditions. The images were evaluated individually by three radiologists, in ideal conditions for radiographic interpretation and with no access to the resources of imaging manipulation from the digital system. The results were rated according to the following criteria: 0 - absence of radiolucence in the enamel: 1 - radiolucence confined to the enamel, 2 - radiolucence in the enamel to the limit dentine-enamel, 3 - radiolucence in the enamel and in the half outer part of the dentine, 4 - radiolucence in the enamel reaching to the half inner part of the dentine. The gold standard was obtained by histological study. Data were compared by the Friedman`s test (P <= 0.05). The results obtained with the conventional radiographic films were similar to those obtained with both direct digital radiographs and gold standard; however, the results obtained with the digital radiographic system were significantly lower than those observed in the histological analysis. In the conditions of this study, it was concluded that the direct digital radiographic method significantly underestimate the extension of the occlusal caries lesions in primary molars.

Made available in DSpace on 2014-06-11T19:31:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2005Bitstream added on 2014-06-13T20:21:53Z : No. of bitstreams: 1 silva_jl_dr_araca.pdf: 803850 bytes, checksum: a13420fee8c9eac95ae85dcbb9659489 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A película radiográfica é uma tecnologia que os cirurgiões-dentistas estão mais familiarizados estando confortáveis em termos da técnica e da interpretação. A radiografia digital é um avanço que está sendo adotado lentamente pelo cirugião-dentista, oferecendo algumas vantagens distintas sobre a película. O propósito deste estudo é comparar o sistema radiográfico digital Digora com a digitalização da radiografia convencional, avaliando a densidade radiográfica do processo de reparo alveolar na região de molares inferiores inclusos após exodontia em humanos. Os princípios e técnica para a exodontia foram padronizados assim como para a obtenção das imagens radiográficas. Imagem sugestiva de tecido ósseo mineralizado foi observada nos períodos de 60 e 90 dias, comparando os sistemas digital e convencional digitalizado. A estatística sugere perda nos valores da densidade, nos períodos estudados, para o sistema das radiografias convencionais digitalizadas em relação ao sistema Digora. Os resultados obtidos permitem concluir que a qualidade da imagem convencional digitalizada é menos precisa quando comparada a digital, para o acompanhamento do reparo ósseo pós-operatório. / Conventional radiographic film It is a technology that the surgeon-dentists more are made familiar being comfortable to in terms of the technique and the interpretation. The digital x-ray is an advance that is being adopted slowly for the dentistry. The digital image incorporates computer science in the captation, the exposition, the distinction, and the storage of the direct radiographic images. The digital image offers some distinct advantages on the film, but as all the emergent technology presents new different challenges and so that the users surpass them. The intention of this study was to evaluate through the radiograpic examination for the Digora system the radiographic density of the behavior of the fabric bone during the process of repair in the region of molar enclosed inferiors after exodontia in human beings. Standardized procedures had been used for the surgery of the patients as well as for the attainment of the radiographic images. Bone suggestive fabric image mineralized was observed in the periods of 60 and 90 days comparing the conventional and digital method. The gotten results allow to conclude that the quality of the digital conventional image is lower efficient than the digital one gotten directly for the accompaniment of the postoperative bone repair.

Thesis (M.S.D.)--Indiana University School of Dentistry, 2009. / Title from PDF t. p. (viewed Aug. 21, 2009) Advisor(s): Mychel Vail, Acting Chair of the Research Committee, Joseph Legan, Kenneth Spolnik, Susan L. Zunt, Edwin Parks. Curriculum vitae. Includes abstract. Includes bibliographical references (leaves 109-120).

Orientador: Guilherme Monteiro Tosoni / Resumo: O objetivo deste estudo foi avaliar a confiabilidade de dois métodos radiográficos de determinação da maturação esquelética das vértebras cervicais e a concordância com o método baseado nas imagens radiográficas de mão e punho. Foram analisadas imagens radiográficas digitais cefalométricas laterais e de mão e punho de 120 indivíduos, com idades variando entre 6 e 18 anos. Para o estudo da repetibilidade e reprodutibilidade, as imagens radiográficas foram interpretadas por 4 examinadores (2 radiologistas e 2 ortodontistas) em dois momentos distintos de acordo com os métodos de Hassel e Farman (VC1) e Baccetti et al. (VC2). Para o estudo de concordância, o método de Fishman também foi realizado pelos quatro examinadores. Para as análises estatísticas foi utilizada estatística Kappa (ҡ), com ponderação linear, seguida do cálculo dos intervalos de confiança (IC95%) e Coeficiente de Correlação Intraclasse (CCI). Os resultados da análise intra-examinador indicaram calibração "quase perfeita" para os quatro examinadores (ҡ>0,81) em todos os métodos de análise. Os limites inferiores dos IC estiveram todos acima de 0,71 para a análise inter-examinador. Os valores de CCI para reprodutibilidade inter-examinador foram considerados "excelentes" para os limites inferiores de todos os IC (≥0,91). Embora a proporção total de diagnósticos concordantes (acurácia) obtida nos métodos VC1 e VC2 tenha sido, respectivamente, 42% e 50% para os ortodontistas e 42% e 40% para os radiologistas, o cruza... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate the reliability of two radiographic methods to determine the skeletal maturation of the cervical vertebrae and the concordance with the method based on hand and wrist radiographic images. Were analyzed lateral cephalogram, hand and wrist digital radiographic images of 120 individuals, ranging from 6 to 18 years. For the study of repeatability and reproducibility, the images were interpreted by 4 examiners (2 radiologists and 2 orthodontists) on distinct moments, according to the methods of Hassel e Farman (CV1) and Bacetti et al. (CV2). For the concordance study, the Fishman method was also applied. Statistical analysis was performed using Kappa (ҡ), with linear weighting, followed by the calculation of confidence intermission (CI95%) and the Intraclass Correlation Coefficient (ICC). The intra-examiner analysis results indicated 'almost perfect' calibration for the examiners (ҡ>0,81) in all methods. The lower limits of Cis were all above 0.71 for the interexaminer analysis. ICC values for inter-examiner reproducibility were considered 'excellent' for the lower limits of all Cis (≥0.91). Although the total proportion of concordant diagnosis (accuracy) obtained on CV1 and CV2 methods was 42% and 50% for orthodontists and 42% and 40% for radiologists, the crossing of all Cis95% showed no significant difference. Both methods of determination of skeletal maturation of the cervical vertebrae are reliable, since they presented excellent repeatability and reproducibility. These methods showed substantial concordance with the method using radiographic images of the hand and wrist. Moreover, orthodontists and radiologists interpreted them with the same precision / Mestre

Submitted by MARCELO LELIS ZUPPARDO (ortodontiazuppardo@hotmail.com) on 2018-08-01T23:43:51Z No. of bitstreams: 1 Versão FINAL 01.08.2018.pdf: 1738428 bytes, checksum: ea89ecbcd914fe55c572f405cd81df64 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-08-03T12:52:56Z (GMT) No. of bitstreams: 1 zuppardo_ml_dr_sjc.pdf: 1738428 bytes, checksum: ea89ecbcd914fe55c572f405cd81df64 (MD5) / Made available in DSpace on 2018-08-03T12:52:56Z (GMT). No. of bitstreams: 1 zuppardo_ml_dr_sjc.pdf: 1738428 bytes, checksum: ea89ecbcd914fe55c572f405cd81df64 (MD5) Previous issue date: 2018-06-06 / Este estudo comparou dois protocolos cirúrgicos, corticotomia e corticotomia com decorticalização, em ratos para verificar alteração na movimentação ortodôntica convencional. 60 animais foram divididos aleatoriamente: Grupo controle (GC) - movimentação ortodôntica convencional; Grupo 1 (G1) -movimentação ortodôntica e corticotomia; Grupo 2 (G2) - movimentação ortodôntica com corticotomia e decorticalização. Os animais foram eutanasiados após 7 e 14 dias. No G1 e G2 houve uma maior movimentação ortodôntica comparado aos animais do GC aos 14 dias (p = 0,009 e 0,016) com uma maior área radiográfica interradicular, menor volume ósseo/volume total, menor área final e menor porcentagem de osso. Aos 7 dias os animais do G2 apresentaram menor volume de osso/volume total comparado com GC e aos 14 dias os animais do G2 apresentaram uma menor medida linear da crista óssea comparado com o GC. Os animais do GC aos 14 dias apresentaram uma maior área final comparado aos 7 dias, enquanto o G2 apresentou maior número de células TRAP positivas tanto aos 7 quanto aos 14 dias comparado com o G1. Na análise histológica aos 7 dias houve frequente reabsorção radicular inicial geralmente associada às áreas de hialinização e aos 14 dias, presença do infiltrado inflamatório e com menor ocorrência de áreas hialinas. O padrão de reabsorção radicular iniciado no 7º dia de movimento e consolidado no 14º dia. Concluímos que a corticotomia acelera a movimentação ortodôntica em 14 dias independente da magnitude da injúria cirúrgica / This study compared two surgical protocols, corticotomy and decorticalization corticotomy, in rats to verify alteration in conventional orthodontic movement. 60 animals were randomly divided: Group 1 (G1) orthodontic movement and corticotomy, and Group 2 (G2) orthodontic movement with corticotomy and decorticalization. The animals were euthanized after 7 and 14 days. In G1 and G2, there was a greater orthodontic movement compared to CG animals at 14 days (p = 0.009 and 0.016) with a higher interradicular radiographic area, lower bone volume / total volume, lower final area and lower percentage of bone. At 7 days the G2 animals presented lower bone volume / total volume compared to CG and at 14 days G2 animals presented a smaller linear measure of bone crest compared to CG. GC animals at 14 days presented a larger final area compared to 7 days, while G2 presented a higher number of TRAP cells positive at 7 and 14 days compared to G1. In the histological analysis at 7 days, there was frequent initial root resorption generally associated with hyalinization areas and at 14 days, presence of inflammatory infiltrate and less occurrence of hyaline areas. The root resorption pattern started on day 7 of movement and was consolidated on the 14th day. We conclude that corticotomy accelerates orthodontic movement in 14 days regardless of the magnitude of the surgical injury.

Esta pesquisa teve por objetivo avaliar a reabsorção radicular externa em dentes tratados endodonticamente após tratamento ortodôntico, por meio de análise das imagens das radiografias panorâmica final digitalizada, convencional periapical digitalizada e digital direta, como também comparar os métodos radiográficos empregados. Foram selecionados, após uma avaliação de 2.130 documentações ortodônticas 20 dentes de pacientes com documentação ortodôntica completa, boas condições de saúde, faixa etária entre 25 a 50 anos de ambos os sexos e com dentes anteriores (incisivo central ou lateral) tratados endodonticamente antes da realização do tratamento ortodôntico. De cada documentação ortodôntica completa foi selecionada a radiografia panorâmica inicial e final e, posteriormente, foram obtidas duas radiografias periapicais atuais de cada dente, uma pela técnica convencional e outra digital direta. Após a obtenção e identificação das radiografias, as imagens da panorâmica final digitalizada, radiografia periapical convencional digitalizada e digital direta foram analisadas na tela do computador por três especialistas (endodontista, ortodontista e radiologista). Estes avaliaram se a reabsorção radicular externa estava presente ou ausente no dente tratado endodonticamente após tratamento ortodôntico, bem como compararam os métodos empregados verificando sua confiabilidade. Os seguintes parâmetros foram observados: a) lesão periapical, b) espaço pericementário e c) limite do tratamento endodôntico. As observações foram submetidas à análise estatística chegando-se às seguintes conclusões: 1) A maioria dos ortodontistas não utiliza radiografias periapicais para avaliar os dentes tratados endodonticamente antes do tratamento ortodôntico, o que pode comprometer o andamento e o resultado final do tratamento, visto que a reabsorção radicular não apresenta um caráter sintomatológico no seu diagnóstico; 2) Quanto à reabsorção radicular externa, os examinadores apontaram que houve um incremento desta, na maioria do tipo suave e localizada na região apical, e que a radiografia digital direta foi o método radiográfico mais eficiente na determinação deste diagnóstico. / In this research, the assessment of the external root resorption was carried out in endodontically treated teeth after orthodontic treatment, through the analysis of the image of the digital panoramic radiography, the digital periapical conventional and direct digital; as well as the employed methods were comparatively appraised. It was selected, after an evaluation of 2,130 orthodontic records from two centres of orthodontic studies, 20 teeth of patients with complete orthodontic records, good health conditions, age group between 25 and 50 years-old of both sexes and with front teeth (central or lateral incisor) endodontically treated before the accomplishment of the orthodontic treatment. An initial and final panoramic radiography were selected from each orthodontic record, and, later two current radiographies were obtained from each patient, one by conventional technique and the other by direct digital. After the obtaining and identification of the radiographies, the images of the digital panoramic of the digital conventional and of the direct digital were analyzed on the computer screen by three experts (an endodontist, an orthodontist and a radiologist) who evaluated whether the external root resorption was present or absent in the endodontically treated tooth after the orthodontic treatment and comparatively assessed the employed methods, verifying their reliability; they also observed the following parameters: a) periapical lesion, b) pericemental space, and c) limits of the endodontical treatment. The observations were submitted to a statistical analysis, reaching the following conclusions: 1) most of the orthodontists don\'t use periapical radiographies to evaluate endodontically treated teeth. Before the orthodontic treatment, what can compromise its course and its final results, once the root resorption doesn\'t present a symptomatology in its diagnosis; 2) as for the external root resorption, examiners claimed that there was an increment in it, most in the soft type and located in the apical area, and that the evaluation of the effectiveness of the resorption diagnosis, as well as of the other appraised parameters, indicated that the direct digital radiography obtained better outcomes regarding its identification and its classification.

Esta pesquisa in vitro, avaliou comparativamente a acurácia do diagnóstico do método radiográfico digital com o método radiográfico convencional, na detecção de lesões de cárie oclusal em molares decíduos. O material foi composto por 55 dentes posteriores decíduos, que apresentavam pigmentações e pelo menos um sítio suspeito de lesão de cárie oclusal, sem restaurações e superfícies sem selantes. As radiografias digitais foram executadas com o sistema Dixi3 (Planmeca, Helsink, Finland) e as radiografias convencionais com o filme Insight (Kodak Eastman Co., EUA), ambas de modo padronizado, em idênticas condições geométricas. As imagens foram avaliadas individualmente por três radiologistas, em ideais condições de interpretação radiográfica e sem acesso aos recursos de manipulação de imagens do sistema digital. Os achados foram classificados de acordo com o seguinte critério: 0 - ausência de radiolucidez no esmalte, 1- radiolucidez confinada ao esmalte, 2- radiolucidez no esmalte até o limite dentina-esmalte, 3- radiolucidez no esmalte e na metade mais externa da dentina, 4- radiolucidez no esmalte alcançando a metade mais interna da dentina. O padrão ouro foi obtido pelo estudo histológico. Os dados foram analisados através do teste de Freidman (P <= 0,05). Os resultados obtidos com os filmes radiográficos convencionais foram similares aos resultados obtidos com as radiografias digitais diretas e o padrão ouro, porém os resultados obtidos com o sistema radiográfico digital foram significativamente menores que o histológico. Nas condições deste estudo, concluímos que o método de radiografia digital subestimou a extensão das lesões de cárie oclusal em molares decíduos. / This in vitro research, evaluated the accuracy of the direct digital radiographic method compared to the conventional radiographic method in the analysis of the extension of occlusal carious lesions in primary molars. The material was composed by 55 primary molars presenting pigmentation and, at least, one suspect site of occlusal carious lesion, these teeth had neither restoration nor surfaces with sealant. Digital radiographs were obtained with the Dixi3 system (Planmeca, Helsink, Finland) and the conventional radiographs with the Insight film (Kodak Eastman Co., USA), both in standard form and identical geometrical conditions. The images were evaluated individually by three radiologists, in ideal conditions for radiographic interpretation and with no access to the resources of imaging manipulation from the digital system. The results were rated according to the following criteria: 0 - absence of radiolucence in the enamel: 1 - radiolucence confined to the enamel, 2 - radiolucence in the enamel to the limit dentine-enamel, 3 - radiolucence in the enamel and in the half outer part of the dentine, 4 - radiolucence in the enamel reaching to the half inner part of the dentine. The gold standard was obtained by histological study. Data were compared by the Friedman`s test (P <= 0.05). The results obtained with the conventional radiographic films were similar to those obtained with both direct digital radiographs and gold standard; however, the results obtained with the digital radiographic system were significantly lower than those observed in the histological analysis. In the conditions of this study, it was concluded that the direct digital radiographic method significantly underestimate the extension of the occlusal caries lesions in primary molars.

Doctor of Philosophy / Radiographic film/screen (F/S) images have a narrow latitude or dynamic range. The film’s ability to record and view all the anatomy within the x-ray field is limited by this narrow dynamic range. The advent of digital radiographic means of storing and displaying radiographic images has improved the ability to record and visualise all of the anatomy. The problem still exists in digital radiography (DR) when radiographic examinations of certain anatomical regions are undertaken. In this work, the value of anatomically shaped radiographic contrast-enhancement masks (RCMs) in improving image contrast and reducing the dynamic range of images in DR was examined. Radiographic contrast-enhancement masks are digital masks that alter the radiographic contrast in DR images. The shape of these masks can be altered by the user. Anatomically shaped RCMs have been modelled on tissue compensation filters (TCFs) commonly used in F/S radiographic examinations. The prime purpose of a TCF is to reduce the dynamic range of photons reaching the image receptor and hence improve radiographic contrast in the resultant image. RCMs affect the dynamic range of the image rather than the energy source of the image, that of the x-ray photons. The research consisted of three distinct phases. The first phase was to examine physical TCFs and their effects on F/S radiographic images. Physical TCFs are used in radiographic F/S examinations to attenuate the x-ray beam to compensate for varying patient tissue thicknesses and/or densities. The effect of the TCF is to reduce resultant radiographic optical density variations in the image, allowing the viewer to observe a range of densities within the image which would otherwise not be visualised. Physical TCFs are commonly aluminium- or lead-based materials that attenuate the x-ray beam. A TCF has varying physical thickness to differentially attenuate the iii beam and is shaped for specific anatomical situations. During this project, various commonly used physical TCFs were examined. Measurements of size and thickness were made. Characteristics of linear attenuation coefficients and half-value thicknesses were delineated for various TCF materials and at various energies. The second phase of the research was to model the physical TCFs in a digital environment and apply the RCMs to DR images. The digital RCMs were created with similar characteristics to mimic the shapes to the physical TCFs. The RCM characteristics can be adjusted by the viewer of the image to suit the anatomy being imaged. Anatomically shaped RCMs were designed to assist in overcoming a limitation when viewing digital radiographic images, that of the dynamic range of the image. Anatomically shaped RCMs differ from other means of controlling the dynamic range of a digital radiographic image. It has been shown that RCMs can reduce the range of optical densities within images with a large dynamic range, to facilitate visualisation of all anatomy within the image. Physical TCFs are used within a specific range of radiographic F/S examinations. Digital radiographic images from this range of examinations were collected from various clinical radiological centres. Anatomically shaped RCMs were applied to the images to improve radiographic contrast of the images. The third phase of the research was to ascertain the benefits of the use of RCMs. Various other methods are currently in use to reduce the dynamic range of digital radiographic images. It is generally accepted that these methods also introduce noise into the image and hence reduce image quality. Quantitative comparisons of noise within the image were undertaken. The anatomically shaped RCMs introduced less noise than current methods designed to reduce the dynamic range of digital radiographic images. It was shown that RCM methods do not affect image quality. Radiographers make subjective assessment of digital radiographic image quality as part of their professional practice. To assess the subjective quality of images enhanced with anatomically shaped RCMs, a survey of radiographers and other iv qualified people was undertaken to ascertain any improvement in RCM-modified images compared to the original images. Participants were provided with eight pairs of image to compare. Questions were asked in the survey as to which image had the better range of optical densities; in which image the anatomy was easiest to visualise; which image had the simplest contrast and density manipulation for optimal visualisation; and which image had the overall highest image quality. Responses from 123 participants were received and analysed. The statistical analysis showed a higher preference by radiographers for the digital radiographic images in which the RCMs had been applied. Comparisons were made between anatomical regions and between patient-related factors of size, age and whether pathology was present in the image or not. The conclusion was drawn that digital RCMs correctly applied to digital radiographic images decrease the dynamic range of the image, allowing the entire anatomy to be visualised in one image. Radiographic contrast in the image can be maximised whilst maintaining image quality. Using RCMs in some digital radiographic examinations, radiographers will be able to present optimised images to referring clinicians. It is envisaged that correctly applied RCMs in certain radiographic examinations will enhance radiographic image quality and possibly lead to improved diagnosis from these images.

Doctor of Philosophy / Radiographic film/screen (F/S) images have a narrow latitude or dynamic range. The film’s ability to record and view all the anatomy within the x-ray field is limited by this narrow dynamic range. The advent of digital radiographic means of storing and displaying radiographic images has improved the ability to record and visualise all of the anatomy. The problem still exists in digital radiography (DR) when radiographic examinations of certain anatomical regions are undertaken. In this work, the value of anatomically shaped radiographic contrast-enhancement masks (RCMs) in improving image contrast and reducing the dynamic range of images in DR was examined. Radiographic contrast-enhancement masks are digital masks that alter the radiographic contrast in DR images. The shape of these masks can be altered by the user. Anatomically shaped RCMs have been modelled on tissue compensation filters (TCFs) commonly used in F/S radiographic examinations. The prime purpose of a TCF is to reduce the dynamic range of photons reaching the image receptor and hence improve radiographic contrast in the resultant image. RCMs affect the dynamic range of the image rather than the energy source of the image, that of the x-ray photons. The research consisted of three distinct phases. The first phase was to examine physical TCFs and their effects on F/S radiographic images. Physical TCFs are used in radiographic F/S examinations to attenuate the x-ray beam to compensate for varying patient tissue thicknesses and/or densities. The effect of the TCF is to reduce resultant radiographic optical density variations in the image, allowing the viewer to observe a range of densities within the image which would otherwise not be visualised. Physical TCFs are commonly aluminium- or lead-based materials that attenuate the x-ray beam. A TCF has varying physical thickness to differentially attenuate the iii beam and is shaped for specific anatomical situations. During this project, various commonly used physical TCFs were examined. Measurements of size and thickness were made. Characteristics of linear attenuation coefficients and half-value thicknesses were delineated for various TCF materials and at various energies. The second phase of the research was to model the physical TCFs in a digital environment and apply the RCMs to DR images. The digital RCMs were created with similar characteristics to mimic the shapes to the physical TCFs. The RCM characteristics can be adjusted by the viewer of the image to suit the anatomy being imaged. Anatomically shaped RCMs were designed to assist in overcoming a limitation when viewing digital radiographic images, that of the dynamic range of the image. Anatomically shaped RCMs differ from other means of controlling the dynamic range of a digital radiographic image. It has been shown that RCMs can reduce the range of optical densities within images with a large dynamic range, to facilitate visualisation of all anatomy within the image. Physical TCFs are used within a specific range of radiographic F/S examinations. Digital radiographic images from this range of examinations were collected from various clinical radiological centres. Anatomically shaped RCMs were applied to the images to improve radiographic contrast of the images. The third phase of the research was to ascertain the benefits of the use of RCMs. Various other methods are currently in use to reduce the dynamic range of digital radiographic images. It is generally accepted that these methods also introduce noise into the image and hence reduce image quality. Quantitative comparisons of noise within the image were undertaken. The anatomically shaped RCMs introduced less noise than current methods designed to reduce the dynamic range of digital radiographic images. It was shown that RCM methods do not affect image quality. Radiographers make subjective assessment of digital radiographic image quality as part of their professional practice. To assess the subjective quality of images enhanced with anatomically shaped RCMs, a survey of radiographers and other iv qualified people was undertaken to ascertain any improvement in RCM-modified images compared to the original images. Participants were provided with eight pairs of image to compare. Questions were asked in the survey as to which image had the better range of optical densities; in which image the anatomy was easiest to visualise; which image had the simplest contrast and density manipulation for optimal visualisation; and which image had the overall highest image quality. Responses from 123 participants were received and analysed. The statistical analysis showed a higher preference by radiographers for the digital radiographic images in which the RCMs had been applied. Comparisons were made between anatomical regions and between patient-related factors of size, age and whether pathology was present in the image or not. The conclusion was drawn that digital RCMs correctly applied to digital radiographic images decrease the dynamic range of the image, allowing the entire anatomy to be visualised in one image. Radiographic contrast in the image can be maximised whilst maintaining image quality. Using RCMs in some digital radiographic examinations, radiographers will be able to present optimised images to referring clinicians. It is envisaged that correctly applied RCMs in certain radiographic examinations will enhance radiographic image quality and possibly lead to improved diagnosis from these images.

RESUMO A Expansão Rápida da Maxila é um recurso clínico adotado pelos ortodontistas no tratamento das más oclusões com deficiência transversa real ou relativa da maxila. Esta, inclui uma fase ativa, promovendo a desarticulação dos ossos maxilares por meio da sutura, e uma fase passiva, onde uma série de eventos levam à remodelação óssea e restauração da sutura, com o aumento clínico na largura do palato. Discute-se qual a melhor época para a disjunção e o tempo necessário para que haja a perfeita remodelação óssea. A radiografia oclusal assume aqui um importante papel, pois é por meio desta que se obtém a imagem da sutura palatina mediana permitindo uma análise descritiva de suas condições em todas as etapas do tratamento A nossa proposta no presente estudo, foi a de medir as densidades ópticas da sutura palatina mediana antes da disjunção (Fase I), imediatamente após a disjunção, (Fase II) e após contenção de três meses (Fase III), usando um sistema de imagem digital, comparando-as e correlacionando-as com a radiografia oclusal convencional. A amostra, constituída por 31 (trinta e um) pacientes que se submeteriam à disjunção palatina e que se encontravam em fase de crescimento, foi dividida em:grupo I, constituído pelos pacientes de dentadura mista e grupo II, pelos pacientes de dentadura permanente. Foram obtidas radiografias oclusais e imagens digitais nas fases Fase I, Fase II e na Fase III. Áreas de interesse foram demarcadas nas radiografias digitais, procedendo-se a leitura das densidades ópticas pelo programa Digora for Windows-2.1, e comparando os resultados entre si e com a avaliação subjetiva feita nas radiografias oclusais. Após a análise dos dados pelo teste t de Student pareado, pode-se concluir que 1) as densidades ópticas da sutura palatina mediana na fase final, mostram valores inferiores aos da fase inicial nos pacientes do grupo I; 2) as densidades ópticas da sutura palatina mediana na fase final, mostram valores semelhantes aos da fase inicial nos pacientes do grupo II; 3) as densidades ópticas finais da sutura palatina mediana não correspondem às iniciais nos pacientes do sexo feminino do grupo I; 4) as densidades ópticas finais da sutura palatina mediana são semelhantes às iniciais nos pacientes do sexo masculino do grupo II; 5) para os pacientes do grupo II não houve diferença significante entre os valores de densidade óptica inicial e final, tanto no sexo masculino como feminino; 6) os resultados encontrados nas imagens digitais são compatíveis com os encontrados nas radiografias oclusais convencionais. / SUMMARY The Fast Expansion of the Jaw is a clinical resource adopted by the ortodontists in the treatment of the bad occlusions with real or relative deficiency transversal, of the jaw. This, includes a phase, promoting the disarticulation of the maxilarys bones by means of the suture, and a passive phase, where a series of events takes to the bone remodelling and restoration of the suture, with the clinical increase in the width of the palate. The best time for the disjunction and the necessary time is argued which so that it has the perfect bone remodelling. The oclusal radiography assumes an important role here, therefore it is for way of this that if gets the image of the medium palatine suture allowing to a descriptive analysis of its conditions in all the stages of the treatment our proposal in the present study, was to measure the optic densities of the medium palatine suture before the disjunction (Phase I), immediately after the disjunction, (Phase II) and after containment three months (Phase III), using a system of digital image, comparing and correlating them with the conventional oclusal radiography. The sample, consisting of 31 (thirty one) patient that would submitted the palatine disjunction and that found in growth phase, divided in Grave I, constituted of the patients of mixing set of teeth and group II, for the permanent set of teeth patients. Oclusal radiography and digital images in the phases had been gotten Phase I, Phase II and in Phase III. Areas of interest had been demarcated in the digital x-rays, proceeding it reading from the optic densities for the Digora program for Windows-2.1, and comparing the results among themselves. With the subjective evaluation in the oclusal radiographies.(After the analysis of the data by student T test could be concluded that1) the opitic densities of the medium palatine suture in the final phase, show inferior values to the ones of the initial phase in the patients of group I;2) the optic densities of the medium palatine suture in the final phase, show similar values to the ones of the initial phase in the patients of group II;3) the final optic densities of the medium palatine suture do not correspond to the initials in the patients of the female groupI;4) the final opitic densities of the medium palatine suture are similar to the initials in the patients of the male group II;5) for the patients of group II it did not have significant difference betweenthe values of initial and final opitic density, as much in the male and female groups6) the results found in the digital images are compatible wit those found in the conventional oclusal radiographics.