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Epidemiological studies that conform to the highest possible standards of research design are required to provide good quality caries data necessary for disease surveillance, health needs assessments and the evaluation of oral health intervention strategies. Caries detection methods used in such studies should be suitable for “blinding” examiners collecting research data, to exposure or group allocation of participants in order to minimise the introduction of bias. The purpose of the studies in this thesis was therefore to assess the diagnostic performance and the pragmatic applicability of the use of intra-oral photographs as a caries detection method in epidemiological studies.Phase I compared the caries detection performance of intra-oral photographic assessments with visual examination and histology as the reference standard. Extracted teeth were assessed for caries using visual examination and assessments of photographs. The diagnostic decisions made were compared to histology. The visual examination and photographic assessments method had median sensitivity values of 65.6% and 81.3%; and median specificity values of 82.4% and 82.4% respectively. The two methods both had good intra- and inter-examiner reliability.The study in phase II compared the assessment of intra-oral photographs as means of detecting dental caries with visual dental examination in 5-year-olds and 10/11-year-olds in an epidemiological survey setting. 5-year-olds and 10-/11-year-olds were visually examined. Intra-oral photographs taken of the children’s teeth were also assessed by the same examiners. There was good intra-examiner reliability for both the visual and the photographic methods for all the examiners. However the photographic method was found to be lengthier than visual examination.Phase III compare caries data obtained from a full mouth visual examination with that obtained from eight, six and four intra-oral photographs of index teeth in two groups of children aged 5 years and 10/11 years. The views of users of the methods (examiners) as well as those on whom the methods were used (children) were also sought using focus group discussions. The examiners found it easier to make caries detection decisions on intra-oral photographs of primary teeth and they suggested that the use of other drying methods are required to improve the utility of photographic method. Generally, the intra-oral camera was well received by the children as a means of caries detection. Caries information obtained from the assessment of eight intra-oral photographs of the primary dentition was comparable to that from full mouth visual examination and may be used as an alternative caries detection method in situations where the visual examination method may not be applicable.

Au cours des vingt dernières années, les facettes céramiques sont devenues une solution esthétique très répandue en raison de leur conception de préparation peu invasive, de leurs propriétés biocompatibles, de leur similitude avec la couleur naturelle des dents, ainsi que de leur translucidité et de leur résistance mécanique aux forces occlusales et à l’usure [1]. La définition des facettes dentaires est celle de « coquilles » très minces, faites sur mesure de matériaux de la couleur de la dent, conçues pour recouvrir la face avant ou la face supérieure des dents afin d' en améliorer l'esthétique et/ou corriger des problèmes occlusaux. Elles sont collées aux dents et pourront en modifier la couleur la forme, et le volume [2].Elles trouvent ainsi de multiples indications à différents endroits sur les arcades dentaires sur les faces vestibulaires des dents antérieures ou plus récemment pour restaurer les surfaces occlusales corriger une occlusion déficiente [3, 4].Ces restaurations modernes se sont développées avec l'arrivée de nouveaux matériaux de reconstructions et de collages, ainsi que de nouveaux modes de conception et fabrication répondant à des exigences de simplicité, de rapidité et de précision.Pour préparer la dent à recevoir une facette, l'oscillation d’inserts ultrasonores a été proposée pour améliorer la finition des lignes marginales et optimiser l’état de surface [5].Pour leur fabrication, outre les méthodes prothétiques classiques, la CFAO (conception assistée par ordinateur - fabrication assistée par ordinateur) au développement exponentiel [6, 7 permet de réaliser une prothèse restauratrice en une seule visite en clinique avec la précision que permettent l’optique (empreintes) et la robotique (fabrication de la facette) ;[8-14]. D’autre part l’apparition de nouvelles céramiques a permis d'améliorer leur esthétique et d'augmenter leur durabilité, qu'elle soit antérieure ou occlusale.Notre première étude portait sur de nouveaux outils permettant d'optimiser la procédure de préparation des facettes. L'utilisation ou non d‘inserts oscillants sur la qualité de l'état de surface de la dent traitées pour une telle préparation. Cette question importante et récurrente, [15] pose le problème de la qualité de l'état de surface destiné à recevoir par collage une pellicule de céramique de faible épaisseur. La pérennité de ce type de prothèse dépend essentiellement du collage avec les tissus dentinaires préparés [16, 17]. La littérature, atteste d’une meilleure qualité de collage entre des surfaces dentaires rugueuses et les matériaux de restauration [18-22]. Toutefois, une question se pose concernant la qualité de cette rugosité lorsque / The first chapter of the thesis relieved the dentists from thinking a lot about the produced roughness regardless to the preparation tool. The roughness is a critical factor to the stability, to the retention, and eventually to the success of the ceramic veneers especially for the esthetic anterior veneers. This will speed up the procedure of achieving a fast treatment for the patients with the CAD-CAM systems. For the upcoming steps, an investigation is recommended to estimate the amount of the inquired roughness to achieve the minimum necessary adhesion value for the retention of the ceramic veneers, and vice versa, another investigation to evaluate the capability of the preparation tools in transferring the same roughness from the preparation tool grains to the target surface (dentin or enamel).152The second study had filled the gap of how to evaluate the IOS systems regardless to the recent common criteria, and the thesis created a novel measure (noise) to be used. The study asks the dentists to pay attention to other criteria to consider when buying an IOS system regardless to the criteria that already exists and had been directed by the producing companies. The thesis states that the noise increases when the direction of the IOS is changed. More attention should be paid at the transitional lines between the scanned surfaces while designing the digital model. An enhancement is demanded to compensate for (or if possible, to eliminate) this noise.

Dental caries are one of the most prevalent chronic diseases. Worldwide 60 to 90 percent of school children and nearly 100 percent of adults experienced dental caries. The management of dental caries demands detection of carious lesions at early stages. The research of designing diagnostic tools in caries has been at peak for the last decade. This research aims to design an automated system to detect and score dental caries according to the International Caries Detection and Assessment System (ICDAS) guidelines using the optical images of the occlusal tooth surface. There have been numerous works that address the problem of caries detection by using new imaging technologies or advanced measurements. However, no such study has been done to detect and score caries with the use of optical images of the tooth surface. The aim of this dissertation is to develop image processing and machine learning algorithms to address the problem of detection and scoring the caries by the use of optical image of the tooth surface.

A research report submitted to the School of Oral Health Sciences, Faculty of Health Sciences, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Dentistry in the branch of Prosthodontics Johannesburg, 2017 / Purpose: To perform a comparative analysis of the accuracy of intra-oral and extra-oral digital scanners when used for the milling of a long-span implant supported superstructure framework. Method: Three intra-oral and three extra-oral scanners were used to measure a master model containing five implant analogues. The three-dimension positions of the implant analogues were measured with a coordinate measuring machine. The digital data from the scanners were used to mill the implant positions in aluminium blanks from a single milling device. These implant positions were measured at the same points as the master model. The three-dimensional differences were calculated to provide a measure of the most accurate frameworks. Results: For the intra-oral scanners, the further the measurement between points, the greater the standard deviation (the poorer the precision) and the poorer the mean accuracy. However, these were clinically acceptable over short distances. For the extra-oral scanners, there was no correlation between the length of the measured distances and the accuracy of the produced framework. All the extra-oral scanners were clinically acceptable for complete-arch prostheses. Conclusions: Noting the limitations of this study and the use of a milling centre to mill the frameworks, for the intra-oral scanners, the 3Shape Trios® (3Shape, Copenhagen, Denmark) can be used for measurements up to 21,5mm and the Sirona CEREC OmniCam (Sirona Dental Systems, Inc., Bensheim, Germany) can be used for measurements up to 34mm. The extra-oral scanners used in this study can be used for complete-arch implant prosthetics. The accuracy of these is relative to the model or impression created. Steps should therefore be made to ensure the accuracy of the model such as the use of a verification jig / MT2017

O diagnóstico precoce de focos de infecção dentários é de fundamental importância para prevenir a ocorrência de maiores injúrias locais ou sistêmicas. Dentre os diversos métodos utilizados para complementar os achados radiológicos das alterações dentoalveolares surge uma alternativa: a cintilografia tomográfica (SPECT/CT), que permite a fusão de achados morfológicos com alterações metabólicas. Com o objetivo de estabelecer o diagnóstico precoce e acurado de processos infecciosos dentários, foram estudadas 320 áreas dentárias em mandíbula e maxila em (10 pacientes de ambos os sexos selecionados por meio de exames clínicos e radiológicos convencionais, seguidos de cintilografia tomográfica com e sem aparato blindador de raios gama. Os exames cintilográficos foram realizados no Serviço de Medicina Nuclear do Hospital Israelita Albert Einstein (HIAE). Para isso, foi administrado para cada paciente o radiofármaco tecnécio 99- metilenodifosfonato (99mTc-MDP) via endovenosa com a dose de 37mBq/3Kg de peso corporal do paciente. Após o período de acúmulo de três horas, foi realizado o protocolo de aquisição de imagens. Todas as imagens foram analisadas por um médico nuclear e um endodontista, com experiência em cintilografia tomográfica. O resultado obtido por meio do exame radiográfico intrabucal pela técnica periapical digital mostraram 6 imagens positivas, em um total de 1,87% da amostra; exame do mapeamento cintilográfico dos ossos da face com a utilização do blindador de raios gâma revelou 9 imagens positivas, correspondendo a 2,81% do total de áreas estudadas, havendo diferença estatisticamente significante ao nível de 95% pelo teste qui-quadrado. Pode-se concluir que o SPECT/CT permitiu identificar as alterações periapicais em maior número quando comparadas ao exame radiográfico periapical e ao mapeamento cintilográfico dos ossos da face com a utilização do blindador de raios gama; o exame de SPCET/CT além de mostrar imagens mais detalhadas, permitiu também localizar com exatidão as áreas alteradas. / The early diagnosis of cases with dental infection is very important to prevent the occurrence of major local or systemic injuries. With many methods used to complement the radiological findings of the bone alterations there\'s the tomographic scintigraphy witch allows the fusion of morphological and metabolic findings. With the objective of the establishment of early diagnosis and accurate dental infectious processes, it was studied 320 dental areas in maxilla and mandible (10 patients) selected randomly, through conventional radiological exams, followed by tomographic scintigraphy with and without intra-oral apparatus. The scintilographic exams were done at the Nuclear Medicine Service of Hospital Israelita Albert Einstein. For that, methylenediphosphonate-technetium-99m (99mTc-MDP) was dispensed intravenous. After the period of accumulation of 3 hours, the image acquisition protocol was taken. This protocol includes images from the top of the head to the neck. After the image analyzes, statistics was done. The intrabucal radiograph exam by the digital periapical technique showed 6 positive images, in a total of 1.87% of the total sample, Intra-oral apparatus showed 9 positive images, in a total os 2,81% of the sample and SPECT/CT exam revealed 15 positive images, corresponding to 4.28% of the total studied areas, showing statistical significance by the level of 95% of qui-square. We could conclude that SPECT/CT allowed identifying the endodontic infections in a larger number when compared with the radiograph exams; and the SPECT/CT exam showed to be of great interest by allowing the union of the diagnosis precocity with the image detail, presenting exact localization of inflammatory/infectious alterations due to the presence of the CT.

Made available in DSpace on 2015-07-22T20:49:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-25. Added 1 bitstream(s) on 2015-08-11T03:25:32Z : No. of bitstreams: 1 Publico-00400.pdf: 1485085 bytes, checksum: 122509d3ca7728c04b3beb00ceac8a98 (MD5) / Associação Fundo Incentivo a Psicofarmacologia (AFIP) / Centros de Pesquisa, Inovação e Difusão (CEPID) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Introdução: Esta cada vez mais evidente os efeitos da hipóxia intermitente e da fragmentação do sono, que ocorrem na Síndrome da Apnéia Obstrutiva do Sono, na geração de espécies reativas do oxigênio, levando a doenças cardiovasculares. Objetivo: O objetivo deste estudo foi avaliar o efeito do tratamento com o aparelho intra-oral em parâmetros de estresse oxidativo em pacientes com Síndrome da Apnéia Obstrutiva do Sono moderada a grave. Métodos: Pacientes com SAOS moderada a grave, ambos os sexos, idade entre 25 e 65 anos, IMC menor que 35 Kg/m2, com boas condições dentárias, participaram deste estudo randomizado, cruzado, duplo-cego com um mês em cada tratamento com Continuous Positive Airway Pressure (CPAP), um aparelho intra-oral (AIO) e um aparelho placebo. Avaliamos a sonolência excessiva diurna subjetiva pela Escala de Sonolência de Epworth (ESE), parâmetros polissonográficos e parâmetros de estresse oxidativo (Thiobarbituric Acid Reactive Substances, Superóxido Dismutase, Catalase, Vitaminas C, E, B6, B12 e Folato, Homocisteína, Ácido Úrico). Resultados: 29 pacientes (24 homens e 5 mulheres) participaram deste estudo, com idade média de 47,3 ± 8,9 anos, IMC de 28,4 ± 3,6 Kg/m2 e escores na Escala de Sonolência de Epworth de 11,4 ± 5,3. Tanto o aparelho intra-oral quanto o CPAP levaram a uma redução no Índice de Apnéias e Hipopnéias, porém o efeito com o CPAP foi melhor (basal: 42,3 ± 4,5; placebo: 48,7 ± 5,6; AIO: 26,7 ± 4,8; CPAP: 3,2 ± 0,4; p < 0,05). O uso do CPAP também levou a uma diminuição no escore da ESE (basal: 11,3 ± 1,0 x CPAP: 9,7 ± 0,8; p < 0,05), embora a adesão ao AIO tenha sido maior que ao CPAP (86,3 ± 3,0 x 72,0 ± 4,2%; p < 0,05). Quanto aos parâmetros de estresse oxidativo, observamos uma queda dos níveis de atividade da enzima catalase em relação aos valores basais com o AIO (basal: 115,8 ± 5,2; placebo: 102,7 ± 4,4; AIO: 95,3 ± 4,6; CPAP: 107,1 ± 3,8 U/mg Hb; p < 0,01). Além disso, houve um aumento dos valores de vitamina C nas fases placebo e CPAP quando comparados ao basal (basal: 54,9 ± 2,5; placebo: 65,9 ± 3,0; AIO: 62,3 ± 2,6; CPAP: 64,3 ± 2,5 umol/L; p < 0,05) e dos valores de vitamina B6 em todas as fases de tratamento comparados aos valores iniciais (basal: 18,9 ± 1,2; placebo: 22,7 ± 1,5; AIO: 22,2 ± 1,3; CPAP: 24,6 ± 0,9 nmol/L; p<0,05). Conclusão: Podemos concluir que, embora o CPAP tenha sido mais eficaz na melhora clínica e nos parâmetros polissonográficos de pacientes com SAOS moderada a grave, a adesão ao tratamento AIO neste grupo de pacientes foi mais eficiente e favoreceu a redução em uma das enzimas que participam da remoção de espécies reativas de oxigênio. / Introduction: Obstructive Sleep Apnea Syndrome (OSAS) is associated with increased cardiovascular morbidity and mortality. The exact nature of the underlying pathophysiology of cardiovascular morbidity in OSAS patients has not been fully elucidated. One of the underlying mechanisms is the formation of Reactive Oxygen Species (ROS), increasing oxidative stress (OS) due to the intermittent hypoxia. Studies with OSAS patients highlighted an increase in markers of OS associated to vascular risk. Authors have demonstrated a decrease of OS after Continuous Positive Airway Pressure (CPAP). OS reduction by means of the Oral Appliance (OA) is yet to be comprehended. Objective: The purpose of this study was to evaluate the effect of an OA compared with CPAP regarding OS parameters in moderate to severe OSAS patients with a randomized, double blind and placebo controlled trial. Methods: Subjects were patients with moderate to severe OSAS, of both genders, BMI under 35, 25-65 years of age, in good dental condition. All patients were submitted to 3 treatments: mandibular repositioning appliance (BRD) in maximal comfortable protrusion, placebo appliance (PA) and CPAP with one month of each treatment and one week washout between them. It was a randomized, cross-over, double blind and placebo controlled trial. Epworth Sleepiness Scale (ESS), polysomnographic and OS parameters (Thiobarbituric Acid Reactive Substances -TBARS, Superoxide Dismutase, Catalase, Vitamins C, E, B6, B12 and Folate, Homocysteine, and Uric Acid) were evaluated at each phase (baseline and after one month of each treatment). Results: 29 patients (24 men and 5 women) took part of the study, with a mean age of 47.3 ± 8.9 years, BMI of 28.4 ± 3.6 Kg/m and scoring on ESS of 11.4 ± 5.3. Both OA and CPAP treatments led to a decrease on the Apnea and Hypopnea Index (AHI). The last, however, demonstrated better efficacy (baseline: 42.3 ± 4.5; PA: 48.7 ± 6.5; OA: 26.7 ± 4.8; CPAP: 3.2 ± 0.4; p < 0.05), besides improving ESS (baseline: 11.3 ± 1.0 versus CPAP: 9.7±0.8; p < 0.05). Notwithstanding, compliance rate during OA period was higher than during CPAP (86.3 ± 3.0% versus 72.0 ± 4.2%; p < 0.05). For the OS parameters, a significant drop in the levels of catalase activity was observed after OA compared to the baseline period (baseline: 115.8 ± 5.2; PA: 102.7 ± 4.4; OA: 95.3 ± 4.6; CPAP: 107.1 ± 3.8 U/mg Hb; p<0.01). Moreover, there was an increase in vitamin C levels after PA and CPAP (baseline: 54.9 ± 2.5; PA: 65.9 ± 3.0; OA: 62.3 ± 2.6; CPAP: 64.3 ± 2.5 umol/L; p<0.05), and in vitamin B6 after all treatment periods compared to initial values in baseline period (baseline: 18.9 ± 1.2; PA: 22.7 ± 1.5; OA: 22.2 ± 1.3; CPAP: 24.6 ± 0.9 nmol/L; p<0.05). Conclusion: Even though CPAP proved to be more effective in attenuating OSAS and its subjective associated complaints, the better compliance to OA in this group of patients supported the reduction of one of the enzymes which participates in ROS removal. / FAPESP: 98/14303 / AFIP: 47.4277/2004-6 / TEDE

O diagnóstico precoce de focos de infecção dentários é de fundamental importância para prevenir a ocorrência de maiores injúrias locais ou sistêmicas. Dentre os diversos métodos utilizados para complementar os achados radiológicos das alterações dentoalveolares surge uma alternativa: a cintilografia tomográfica (SPECT/CT), que permite a fusão de achados morfológicos com alterações metabólicas. Com o objetivo de estabelecer o diagnóstico precoce e acurado de processos infecciosos dentários, foram estudadas 320 áreas dentárias em mandíbula e maxila em (10 pacientes de ambos os sexos selecionados por meio de exames clínicos e radiológicos convencionais, seguidos de cintilografia tomográfica com e sem aparato blindador de raios gama. Os exames cintilográficos foram realizados no Serviço de Medicina Nuclear do Hospital Israelita Albert Einstein (HIAE). Para isso, foi administrado para cada paciente o radiofármaco tecnécio 99- metilenodifosfonato (99mTc-MDP) via endovenosa com a dose de 37mBq/3Kg de peso corporal do paciente. Após o período de acúmulo de três horas, foi realizado o protocolo de aquisição de imagens. Todas as imagens foram analisadas por um médico nuclear e um endodontista, com experiência em cintilografia tomográfica. O resultado obtido por meio do exame radiográfico intrabucal pela técnica periapical digital mostraram 6 imagens positivas, em um total de 1,87% da amostra; exame do mapeamento cintilográfico dos ossos da face com a utilização do blindador de raios gâma revelou 9 imagens positivas, correspondendo a 2,81% do total de áreas estudadas, havendo diferença estatisticamente significante ao nível de 95% pelo teste qui-quadrado. Pode-se concluir que o SPECT/CT permitiu identificar as alterações periapicais em maior número quando comparadas ao exame radiográfico periapical e ao mapeamento cintilográfico dos ossos da face com a utilização do blindador de raios gama; o exame de SPCET/CT além de mostrar imagens mais detalhadas, permitiu também localizar com exatidão as áreas alteradas. / The early diagnosis of cases with dental infection is very important to prevent the occurrence of major local or systemic injuries. With many methods used to complement the radiological findings of the bone alterations there\'s the tomographic scintigraphy witch allows the fusion of morphological and metabolic findings. With the objective of the establishment of early diagnosis and accurate dental infectious processes, it was studied 320 dental areas in maxilla and mandible (10 patients) selected randomly, through conventional radiological exams, followed by tomographic scintigraphy with and without intra-oral apparatus. The scintilographic exams were done at the Nuclear Medicine Service of Hospital Israelita Albert Einstein. For that, methylenediphosphonate-technetium-99m (99mTc-MDP) was dispensed intravenous. After the period of accumulation of 3 hours, the image acquisition protocol was taken. This protocol includes images from the top of the head to the neck. After the image analyzes, statistics was done. The intrabucal radiograph exam by the digital periapical technique showed 6 positive images, in a total of 1.87% of the total sample, Intra-oral apparatus showed 9 positive images, in a total os 2,81% of the sample and SPECT/CT exam revealed 15 positive images, corresponding to 4.28% of the total studied areas, showing statistical significance by the level of 95% of qui-square. We could conclude that SPECT/CT allowed identifying the endodontic infections in a larger number when compared with the radiograph exams; and the SPECT/CT exam showed to be of great interest by allowing the union of the diagnosis precocity with the image detail, presenting exact localization of inflammatory/infectious alterations due to the presence of the CT.

Magister Scientiae Dentium - MSc(Dent) / The aim of this present study was to compare the accuracy of digital and printed study models with plaster study models, that are considered the gold standard. The objectives were to compare the accuracy of measurements obtained from digital and printed study models with those of plaster study models, to establish which type of study model yielded the most accurate measurements in comparison to plaster study models and to identify possible disadvantages and errors that can be made using any of the three types of study models.

Oral and pharyngeal cancer is commonly treated with a combination of radiotherapy and surgery. It is a clinical knowledge that patients often experience severe swallowing disorders following treatment. Since surgical sequelae are instantaneous and obvious, little attention has been paid to other concurrent effects of the treatment. To shed light on this subject, the aim of this thesis was twofold (i) to make a retrospective inventory of the sequelae following treatment and (ii) to perform a prospective, inceptive examination at diagnosis, and to follow-up after radiotherapy, six months and 12 months after surgery. The files of ninety-nine patients revealed that following treatment one-third had to use gastric fistulas and more than nine of ten patients had restricted swallowing capacity. Every second patient could only swallow puréed or liquid food. Adequate intra-oral sensation and discrimination ability is essential for bolus preparation and bolus control, for appropriate elicitation of the swallowing reflex and, hence, for the oral phase of swallowing. At the inceptive examination, the prospective part of the study demonstrated intra-oral discrimination ability in patients was equal to that in healthy controls but was impaired six months after treatment and there was no significant improvement after 12 months. It had been expected that the patient’s healthy, non-tumor side would compensate but it did not. An explanation was found when it was revealed that radiotherapy induced a delayed decline in intra-oral sensation. Sensory decline was not demonstrated within a month after radiotherapy but was manifest six months later. Since the radiotherapy field includes the neck, because of the risk for metastasis, it is highly plausible that pharyngeal sensation declines in a manner corresponding to that found intra-orally when the healthy side is irradiated. In accord with this presumption, pharyngeal swallowing function deteriorated in patents with oral tumors. Cineradiographic evaluation of oral and pharyngeal swallowing function disclosed a significant association between the degree of swallowing dysfunction and the degree of sensory decline and with the degree of impairment of shape recognition. Conclusions: Delayed intra-oral sensory decline, found to be induced by radiotherapy, can be expected to appear in the entire radiation field, including the oral cavity and the pharynx, with adverse effect on swallowing. Testing intra-oral sensation close to the last radiotherapy session is not advisable, because sensory decline does not develop immediately after radiotherapy but manifests after six months. Spontaneous sensory rehabilitation cannot be expected after six months. The significant association between degree of swallowing dysfunction and degree of intra-oral sensory decline and impaired discrimination ability must be considered in the quest for functional rehabilitation of patients treated for oral or pharyngeal cancer.