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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.
161

Perspektivenorientierte Erkennung chirurgischer Aktivitäten im Operationssaal

Meißner, Christian 26 March 2015 (has links)
Die Dissertation beschäftigt sich mit der automatischen Erkennung chirurgischer Aktivitäten im Operationssaal, welche einen wichtigen Bestandteil im automatischen chirurgischen Assistenzprozess darstellt. Die automatische Assistenz ist eine der wichtigen Entwicklungen bei der fortschreitenden Technisierung in der Chirurgie. Es werden Anforderungen an ein Erkennungssystem definiert sowie ein entsprechendes Erkennungsmodell entworfen und untersucht. Die Evaluation bedient sich simulierter chirurgischer Eingriffe mit hoher Realitätsnähe. Die Ergebnisse zeigen eine grundlegende Eignung des Modells für die automatische Aktivitätserkennung multipler Eingriffstypen. Mögliche Weiterentwicklungen könnten die vorgestellte Lösung weiter vorantreiben.
162

Implication des biofilms dans la rhinosinusite chronique et l’évaluation des traitements avec un modèle in vitro

Bendouah, Zohra 08 1900 (has links)
Introduction : La chronicité de la rhinosinusite, sa résistance aux antibiotiques, et ses exacerbations aiguës laissent croire que les biofilms sont impliqués dans la rhinosinusite chronique. Objectifs : Nous avons évalué la capacité des bactéries Pseudomonas aeruginosa, staphylocoques à coagulase négative et Staphylococcus aureus à former des biofilms par un essai in vitro, et si cette capacité de formation a un lien avec l’évolution de la maladie. Nous avons évalué in vitro l’effet de la moxifloxacine, un antibiotique utilisé dans le traitement de la rhinosinusite chronique sur des biofilms matures de Staphylococcus aureus. Méthodes : Trent et une souches bactériennes ont été isolées de 19 patients atteints de rhinosinusite chronique et qui ont subit au moins une chirurgie endoscopique des sinus. L’évolution de la maladie a été notée comme "bonne" ou "mauvaise" selon l’évaluation du clinicien. La production de biofilm a été évaluée grâce à la coloration au crystal violet. Nous avons évalué la viabilité du biofilm après traitement avec la moxifloxacine. Ces résultats ont été confirmés en microscopie confocale à balayage laser et par la coloration au LIVE/DEAD BacLight. Résultat et Conclusion : Vingt deux des 31 souches ont produit un biofilm. La production d’un biofilm plus importante chez Pseudomonas aeruginosa et Staphylococcus aureus était associée à une mauvaise évolution. Ceci suggère un rôle du biofilm dans la pathogenèse de la rhinosinusite chronique. Le traitement avec la moxifloxacine, à une concentration de 1000X la concentration minimale inhibitrice réduit le nombre des bactéries viables de 2 à 2.5 log. Ces concentrations (100 µg/ml - 200 µg/ml) sont faciles à atteindre dans des solutions topiques. Les résultats de notre étude suggèrent que l’utilisation de concentrations supérieure à la concentration minimale inhibitrice sous forme topique peut ouvrir des voies de recherche sur de nouveaux traitements qui peuvent être bénéfiques pour les patients atteints de forme sévère de rhinosinusite chronique surtout après une chirurgie endoscopique des sinus. / Introduction: The role of biofilms in chronic diseases is increasingly recognized. Chronic rhinosinusitis, with its chronic indolent course, resistance to antibiotics, and acute exacerbations, has an evolution that parallels that of other biofilm-related diseases. Objectives: 1-To develop an in vitro method to assess the biofilm formation capacity. 2- To determine whether biofilm-forming capacity of bacteria demonstrated in chronic rhinosinusitis has an impact on persistence of the disease following endoscopic sinus surgery. 3- To determine the in vitro activity of moxifloxacin against Staphyylococcus aureus in biofilm form. Method: Thirty-one bacterial strains recovered from 19 patients with chronic rhinosinusitis at least one year post-endoscopic sinus surgery. Evolution of disease was assessed by questionnaire and endoscopy as favorable or unfavorable. The bacteria were cultured on a 96-well culture plaque and a semi-quantitative method using crystal violet to quantify biofilm production was used. Confirmation of the effect of the antimicrobial agents on viability was performed with confocal laser microscopy, using a LIVE/DEAD BacLight staining. Results: Twenty-two of 31 samples produced a biofilm thicker or equal to the positive control. Biofilm formation was associated with a poor evolution for Pseudomonas aeruginosa and Staphylococcus aureus, but not for coagulase-negative staphylococci. Biofilm treated with moxifloxacin at 1000X (0.1mg/ml – 0.2 mg/ml) gave a 2 to 2.5 log reduction in number of viable bacteria. Conclusion: We have shown that Crystal violet method is able to detect biofilm formation. There is a correlation between in vitro biofilm production by Pseudomonas aeruginosa and Staphylococcus aureus and unfavorable evolution after endoscopic sinus surgery, suggesting a role for biofilm in chronic rhinosinusitis. Increased concentrations of moxifloxacin, easily attainable in topical solutions have a potential role in the management of biofilm infections.
163

Autonomic Reactivity and Adjustment in Middle Childhood

Wagner, Caitlin Reilly 01 January 2016 (has links)
The primary aim of this study was to investigate whether the joint action of the parasympathetic (PNS) and sympathetic nervous system (SNS) influenced three distinct indicators of child adjustment. Although evidence suggests that patterns of reactivity in the PNS and SNS each contribute to adjustment in youth, a paucity of work has examined the interaction between the two systems. Moreover, much of the research on children's autonomic reactivity has overly relied on variable-centered analytic approaches, which aim to predict variance and assume homogeneity in the relations between predictors and outcome. This project also incorporated a person-centered approach to systematically identify individual differences in the interrelation between PNS and SNS reactivity and to classify children into homogeneous autonomic reactivity groups. The person-centered results were then applied to variable-centered analyses to examine how adjustment varied across homogeneous autonomic reactivity groups. Thus, the goal of this study was to apply both variable-centered and person-centered analyses to investigate whether children's autonomic reactivity was related to child adjustment. Children (N = 64, 8-10 years, M = 9.06, SD = 0.81) and one parent completed a psychophysiological laboratory assessment at Wave 1 during which each child's respiratory sinus arrhythmia reactivity (RSAR; an index of PNS reactivity) and skin conductance level reactivity (SCLR; an index of SNS reactivity) was assessed in response to a mirror tracing challenge task. At both Wave 1 and Wave 2, each parent reported on their child's internalizing symptoms, externalizing symptoms, and social competence. The variable-centered analyses revealed that, consistent with hypotheses, the two-way RSAR x SCLR interaction was significant predicting internalizing symptoms at Time 1 and at Time 2. In both cases, RSA withdrawal was associated with fewer internalizing symptoms when coupled with low SCLR. When coupled with high SCLR, RSA withdrawal was associated with more internalizing symptoms at Time 1; however, RSAR was unrelated to Time 2 internalizing when coupled with high SCLR. In addition, SCLR was associated with more social competence and (marginally) fewer externalizing problems over time. The person-centered analyses (i.e., a model-based cluster analysis) identified two distinct clusters based on children's RSAR and SCLR. Children in Cluster 1 showed slight RSA withdrawal combined with SCL activation (modest reciprocal SNS activation) and exhibited marginally more internalizing and less social competence, as compared to children in Cluster 2 who, as a group, showed heightened RSAR (either withdrawal or augmentation) and SNS activation. When a 3-cluster model was examined, results indicated that children who showed modest reciprocal SNS activation (Cluster 1) showed marginally more internalizing symptoms then children who showed strong reciprocal SNS activation (Cluster 2A) and marginally less social competence then children who showed coactivation (Cluster 2B). This study offers important evidence that person-centered analyses can identify differences in autonomic reactivity that are relevant to children's adjustment. Cluster analysis identified only two (i.e., reciprocal SNS activation, coactivation) of the four autonomic profiles assumed to be represented in simple slope analyses in previous work. Thus, incorporating person-centered techniques in future research is an important and likely fruitful approach to investigating how autonomic reactivity contributes to child development.
164

Effets ventilatoire et cardiaque de l'hyperventilation volontaire. Etude chez les volontaires sains et les patients souffrant du trouble panique / Cardio-respiratory effects of voluntary hyperventilation. Study in healthy volunteer and patients with panic disorder.

Besleaga, Tudor 19 October 2011 (has links)
L'objectif du travail était l'étude des effets ventilatoires et cardiovasculaires de l'hyperventilation volontaire (HV) ainsi que psychophysiologiques chez les sujets sains et les patients souffrant de trouble panique. Nous avons mené deux études : la première sur des sujets sains sur lesquels le débit ventilatoire, les mouvements du thorax et de l'abdomen, le pourcentage de CO2 dans l'air expiré (FETCO2), l'électrocardiogramme (ECG) ont été enregistre au cours de deux tests d'hyperventilation : l'un à la fréquence de repos (THV) et l'autre à la fréquence de 20 cycles par minute (THV20). La deuxième étude a porté sur un groupe de sujets sains (groupe contrôle) et un groupe de patients souffrant du trouble panique (TP) sur lesquels le débit ventilatoire et l'ECG ont été enregistrés et les niveaux d'anxiété (Spielbergher), de dépression (Beck), du stress (Holmes), des symptômes de troubles fonctionnels (Profil Végétatif) et des symptômes produits par l'hyperventilation ont été évalués. Les variables ventilatoires classiques ont été calculées cycle par cycle. La forme des cycles ventilatoires a été étudiée en calculant les asters (représentation vectorielle des quatre premières harmoniques d'une décomposition en série de Fourier de chaque cycle respiratoire) ainsi que les triads (complexe trivarié: volume courant Vt, temps d'inspiration Ti et d'expiration Te). Les asters et triads ont été comparés dans les différentes conditions en utilisant un test statistique multi-varié (test de similarité). Les composantes du spectre de la période cardiaque, les périodes cardiaques moyennes et les coefficients de variation de la période cardiaque ont été calculés à partir des intervalles RR de l'ECG. Les résultats du test de similarité montrent que la forme du cycle ventilatoire de repos est modifiée au cours de l'hyperventilation volontaire, mais que la forme cycle à l'HV est conservée à un an d'intervalle et aussi pour les périodes d'HV des deux tests THV et TVH20. L'hyperventilation volontaire modifie significativement les caractéristiques de la ventilation (variables et forme du cycle). Cependant, au cours de l'hyperventilation volontaire ces caractéristiques sont conservées à un an d'intervalle et il semble que la personnalité ventilatoire de repos ne se conserve pas au cours de l'HV, mais l'on retrouve une personnalité « différente » au cours de l'HV. Les variables ventilatoires et leurs coefficients de variation sont modifiés pendant toutes les périodes des deux tests d'hyperventilation. Les variables ventilatoires du groupe contrôle ne sont significativement différentes du groupe TP qu'au cours des trois premières minutes de récupération. La variabilité cardiaque est significativement modifiée au cours des périodes des tests d'hyperventilation volontaire. La variabilité cardiaque est significativement plus faible chez les patients TP que chez les sujets sains et l'analyse des composantes spectrales de la période cardiaque permet de déduire que les patients semblent présenter au repos et pendant l'HV, une activité cardio-vagale plus faible et une activité sympathique plus élevée que les sujets sains. Les patients TP ont des niveaux plus élevés d'anxiété et de dépression que les sujets du groupe contrôle. Au cours des trois première minutes de récupération après l'hyperventilation volontaire à la fréquence de repos, la ventilation est plus élevée chez les sujets présentant une anxiété élevée que chez ceux présentant une anxiété normale à moyenne. Le nombre de symptômes fonctionnels et produits par l'hyperventilation volontaire est aussi plus élevé chez les sujets présentant une anxiété élevée. / The aim of this research was the evaluation of the ventilatory and cardiovascular effects the voluntary hyperventilation (HV) and psychophysiological peculiarities in healthy subjects and patients with panic disorder. We performed two studies: we recorded the airflow, thoracic and abdominal movements, percent of the CO2 in expired air (FETCO2), electrocardiogram (ECG) in a group of healthy subjects during the two voluntary hyperventilation tests: at rest frequency (THV) and at 20 breaths per minute (THV20). The second study was performed on the healthy subjects (control group) and panic disorder patients (TP): airflow and ECG were recorded and the levels of anxiety (Spielbergher), depression (Beck), stress (Holmes), functional symptoms (Vegetative Profile) and symptoms generated by voluntary hyperventilation were evaluated. The classical respiratory variables were calculated cycle by cycle. The shape of ventylatory cycles were studied by calculation of asters (vectorial representation of the first four harmonics obtained by Fourier transformation of each respiratory cycle) and triads (trivariate complex tidal volume - Vt, inspiratory - Ti and expiratory - Te times). The asters and triads were compared in different conditions using statistical multivariate test (similarity test). The components of heart periods spectre, mean cardiac periods and their variation coefficients were determined from the RR intervals of ECG. The results of the similarity test show the change of respiratory cycle shape during voluntary hyperventilation compared with rest, but the shape of the cycle during HV is conserved during one year interval and between periods of HV of two tests THV and THV20. Voluntary hyperventilation changes significantly ventilatory characteristics (variables and shape of cycle). However, these characteristics are conserved during voluntary hyperventilation after one year interval and the rest ventilatory personality is not conserved during HV, but the different personality appears during HV. Ventilator variables and their variation coefficients are modified during all periods of the two hyperventilation tests. The ventilatory variables of the control group compared with TP group differ only during first three minutes of recovery. Heart rate variability is significantly modified during all periods of hyperventilation test. Heart rate variability is significantly diminished in TP patients compared with healthy subjects and the analysis of spectral components of cardiac period allows affirming a weaker cardio-vagal activity and higher sympathetic activity compared with the healthy subjects. The TP patients compared with control group have higher levels of anxiety and depression. The ventilation during three minutes of recovery after voluntary hyperventilation at rest frequency is higher in subjects with high anxiety level compared with subjects with normal and mean level of anxiety. The number of functional symptoms and symptoms caused by voluntary hyperventilation is also higher in subjects with high anxiety.
165

Avaliação da integridade da cortical do seio maxilar em proximidade a lesões periapicais simuladas em maxilas suínas maceradas por meio por meio da TCFC / Integrity evaluation of the cortical sinus in proximity to periapical lesions simulated in macerated swine maxillae by cone beam computed tomography

Santos Junior, Oseas 11 December 2013 (has links)
A detecção de periapicopatias comprometendo a cortical sinusal pode ser subestimada em radiografias periapicais, que é o exame de rotina, pela sobreposição de estruturas. Neste estudo, a sensibilidade, especificidade e reprodutibilidade da TCFC para a avaliação da integridade da cortical sinusal próxima de lesões periapicais (com e sem comunicação oroantral) foram avaliadas em relação a um padrão-ouro (erosões na região periapical de molares superiores em 20 maxilas suínas maceradas). Foi realizada a primeira etapa de aquisições com as maxilas íntegras, visando familiarizar os observadores com a anatomia da maxila suína e excluir da amostra os sítios com defeitos ósseos pré-existentes. Após isso, foram extraídos os primeiros-molares e lesões periapicais foram simuladas com ácido perclórico. A duração da exposição ao ácido foi controlada em dois tempos: T1 que gerou lesões incipientes e T2 que gerou lesões maiores. O estabelecimento de comunicação oroantral deu-se em 22 sítios. Em seguida, os dentes foram reimplantados nos devidos alvéolos. Realizou-se a segunda etapa de aquisições. Dois observadores, devidamente familiarizados com lesões simuladas na maxila suína com e sem comunicação, avaliaram os exames duas vezes, com intervalo de tempo de uma semana. Todos os exames estavam em ordem aleatória em uma estação de trabalho independente contendo o software OsiriX MD. Os resultados demonstraram uma boa acurácia (66 a 78%) e alta especificidade (70 a 98%) com índices moderados de concordância intraobservadores (0,49 e 0,56), porém gerou resultados distintos de sensibilidade (41%, 55%, 78% e 60%) que culminou em um baixo índice de concordância interexaminadores (0,21 e 0,35). A maior dificuldade relatada pelos observadores foi a alta presença de ruído na imagem, influenciada principalmente pela relação do FOV e voxel que acabou afetando a resolução da imagem do exame. / The detection of periapical diseases affecting the cortical sinus may be underestimated in periapical radiographs, which is the method of choice, by overlapping structures. In this study, the sensitivity, specificity and reproducibility of CBCT to assessing the integrity of the cortical sinus near periapical lesions (with and without communication oroantral) were evaluated by comparing with a gold standard (erosions in the periapical region of maxillary molars in 20 maxillae swine macerated). We performed the first step of acquisitions with intact maxillae in order to acquaint the observers with the swine anatomy and delete the sample sites with pre - existing bone defects. After this, we extracted the first premolar and simulated periapical lesions with perchloric acid . The duration of acid exposure was controlled in two stages: generating incipient lesions T1 and T2 which generated larger lesions. Establishing oroantral communication was more related to the proximity with the alveolus then the periapical periodontitis size, generating 22 sites with communication. Then the teeth were reimplanted in the appropriate dental alveoli to the next tomographic acquisitions. Two trained observers evaluated the tests twice, with an interval of a week\'s time. All tests were in random order on a standalone workstation with software OsiriX MD. The results demonstrated good accuracy (66 to 78%) and high specificity (70% to 98%) and moderate rate of intraobserver concordance (0,49 and 0,56)trai, but generated different results of sensitivity (41%, 55%, 78% and 60%) which culminated in a low rate of interobserver concordance (0,35 and 0,21). The main difficulty reported by the observers was the high presence of image noise, mainly influenced by the ratio of the FOV and voxel that ended up affecting the reliability of the examination.
166

Identificação humana através da análise do seio maxilar em radiografias panorâmicas / Human identification by maxillary sinus in panoramic dental radiograph

Musse, Jamilly de Oliveira 18 June 2009 (has links)
Os seios maxilares podem fornecer subsídios de real valor para a identificação forense. A individualidade dos contornos dos seios permite uma análise precisa, minuciosa, diminuindo os riscos de erros durante a atuação do perito. Os objetivos deste estudo foram: avaliar a possibilidade de investigação do sexo e identificação humana individual, pelos seios maxilares e propor três métodos de identificação através das referidas estruturas. A amostra foi composta por 656 radiografias panorâmicas de 328 indivíduos, com idade superior a 20 anos, de ambos os sexos, sendo estes divididos em grupo controle e experimental, de acordo com a ausência ou presença de perda dentária. De cada indivíduo foram utilizadas duas radiografias, uma inicial e outra após dois anos de tratamento ortodôntico. Três métodos foram empregados: dois manuais e um computadorizado. Nas técnicas manuais calculouse a altura e largura dos seios maxilares, em folhas de acetato e realizou-se a análise da morfologia dessas estruturas, por quadrantes. Na computadorizada, foi calculado a área, perímetro e fator de forma dos seios, através do programa IMAGELAB 2000®. A análise das variáveis quantitativas foi realizada empregando técnicas da estatística descritiva (média e desvio padrão), o teste t-Student com variâncias iguais ou desiguais e t-Student pareado. A comparação da morfologia dos seios nas radiografias do mesmo indivíduo foi feita através da observação visual dos quadrantes. Os métodos propostos para análise dos seios maxilares mostraram que a comparação da morfologia e mensurações destas estruturas em radiografias panorâmicas pode ser utilizada para estimativa do sexo e identificação humana individual. A perda dentária no grupo experimental não interferiu na dimensão dos seios maxilares. A incorporação da análise dos seios maxilares associada a outras evidências é passível de ser empregada nos Institutos Médico-Legais, podendo contribuir de forma significativa em casos de identificação humana. / The maxillaries sinus can supply real value subsidies for the forensic identification. The sinus outlines individuality allows an accuracy and meticulous analysis, reducing the mistakes risks during the expert performance. The aims of this study were: to evaluate the possibility of sex estimate and individual human identification for the maxillaries sinus and to propose three identification methods through referred structures. The sample was composed by 656 panoramic dental radiographs of 328 individuals with 20 years superior age, masculine and feminine. They were divided in controls and experimental groups, in agreement with the absence and presence of dental loss. It was used two radiographs of participants, an initial and other after two years of the orthodontic treatment. Three methods were used: two manual and one computerized. In the manual techniques it was calculated the height and width of the maxillaries sinus, in acetate and took place analysis of those structures morphology, for quadrants. In the computerized it was calculated the area, perimeter and factor in way of the sinus, through the IMAGELAB 2000® software. In the analysis of the results, the descriptive statistics were used (average and standard deviation) and the t-Student test with variances same or unequal and pared t-Student, for the quantitative variables and visual observation of the quadrants morphology of each maxillary sinus. The methods proposed for analysis of the maxillaries sinus showed that the morphology comparison and measurements of these structures in panoramic dental radiographs can be used to estimate of the sex and individual human identification. The dental loss in the experimental group didn\'t implicate in the dimension of the sinus maxillaries. The incorporation of the sinus maxillaries analysis associated to other evidences is susceptible to be used at the Forensic Institutes, could contribute in a significant way in human identification cases.
167

Avaliação da relação entre as raízes dos dentes posteriores e o assoalho do seio maxilar em pessoas sem e com fissura labiopalatina

Pagin, Otávio 10 August 2015 (has links)
O seio maxilar apresenta formato distinto e volume variável entre as pessoas e seu assoalho pode ser encontrado em íntimo contato com as raízes dos dentes posteriores, podendo haver protrusão dessas raízes em seu interior. Tal proximidade é de grande relevância frente aos casos de comunicação bucossinusal em potencial ou pela possibilidade de desenvolvimento de um quadro infeccioso de origem odontogênica, em que esse pode vir a se estender para o interior do seio maxilar. Existe uma ausência de trabalhos na literatura acerca da relação estabelecida entre dentes posteriores e o seio maxilar em pessoas com fissura labiopalatina. O objetivo do presente estudo foi identificar e comparar a relação entre o assoalho do seio maxilar e os ápices radiculares dos dentes posteriores em imagens de tomografia computadorizada de feixe cônico em pessoas sem fissura labiopalatina e com fissura transforame incisivo unilateral e bilateral. Foram avaliados 100 indivíduos sem anomalias craniofaciais e 112 com fissura transforame incisivo unilateral ou bilateral, não sindrômicos, utilizando o programa i-CAT® Vision, onde a relação estabelecida pelas estruturas foi convencionada sendo, tipo 0 ou ausência de contato entre as estruturas, tipo 1 ou relação de íntimo contato entre as estruturas sem protrusão radicular no interior do seio maxilar e tipo 2 ou relação de íntimo contato entre as estruturas com protrusão radicular no interior do seio maxilar. Foi utilizado o teste do qui-quadrado para comparar os achados entre os grupos estudados, considerando valor estatisticamente significante quando p≤ 0,05. Foi avaliada a relação do assoalho do seio maxilar com 1679 dentes, totalizando 3664 raízes onde 1883 (51,3%) foram classificadas como tipo 0, 1456 (39,7%) tipo 1 e 325 (8,8%) do tipo 2. Houve diferença estatisticamente significante para a raiz palatina do dente 18 entre os grupos com fissura unilateral e bilateral (p = 0,011), para a raiz mesiovestibular do dente 18 entre os grupos sem fissura e fissura bilateral (p = 0,046), bem como entre os grupos com fissura unilateral e bilateral (p = 0,016) e para a raiz vestibular do dente 24 entre os grupos sem fissura e com fissura bilateral (p = 0,001). Pessoas com fissura transforame incisivo unilateral e bilateral tendem a apresentar maior ocorrência da raiz vestibular do dente 24 (p = 0,027) e mesiovestibular do dente 16 (p = 0,047) em proximidade com o seio maxilar quando comparadas às pessoas sem fissura. Pessoas com fissura transforame incisivo bilateral tendem a apresentar uma maior ocorrência de proximidade com o seio maxilar das raízes vestibular do dente 24 (p = 0,001) e mesiovestibular do dente 18 (p = 0,046) quando comparados às pessoas sem fissura. A avaliação das raízes dos dentes posteriores por meio de imagens de tomografia computadorizada de feixe cônico e sua relação com o seio maxilar oferecem detalhamento e precisão, contribuindo assim para a elaboração de um diagnóstico e plano de tratamento que visam minimizar os riscos de acidentes e complicações. / The maxillary sinus has a remarkable feature and a variable volume among people where the inferior wall may be found in an intimate relation with the posterior teeth roots protruding or not inside the antrum. This proximity is of great relevance considering a potential oroantral communication or the spreading of an odontogenic infection into the maxillary sinus. There is a lack of evidence into the literature regarding the relationship between posterior teeth roots and the maxillary sinus in non-syndromic complete cleft lip and palate patients. This study aimed to evaluate and compare cone beam computed tomography images regarding the relationship between the posterior teeth roots and the maxillary sinus floor in non-cleft lip and palate patients and non-syndromic complete unilateral and bilateral cleft lip and palate patients. Images were interpreted using the i-CAT® Vision software including 100 noncleft patients and 112 presenting non-syndromic complete unilateral and bilateral cleft lip and palate. The relationship between teeth roots and the maxillary sinus floor was established as type 0 or no contact between these structures, type 1 or close contact without root protrusion into the sinus and type 2 or close contact with root protrusion into the sinus. The chi-square test, considering a statistically significant value where p≤0,05, was used to compare data between different groups. The sample included 1679 teeth and 3664 roots where 1883 (51,3%) were classified as type 0, 1456 (39,7%) as type 1 and 325 (8,8%) as type 2. There were statistically significant differences for tooth 18 palatine root between both complete cleft lip and palate groups (p = 0,011), for tooth 18 mesiobuccal root between noncleft and the bilateral groups (p = 0,046) and between both complete cleft lip and palate groups (p = 0,016) and for tooth 24 buccal root between non-cleft and the bilateral group (p = 0,001). Complete unilateral and bilateral cleft lip and palate patients presented a higher occurrence when compared with the non-cleft group of the tooth 24 buccal root (p = 0,027) and the tooth 16 mesiobuccal root (p = 0,047) in proximity with the maxillary sinus. Complete bilateral cleft lip and palate patients had a higher occurrence when compared with the non-cleft group of the tooth 24 buccal root (p = 0,001) and the tooth 18 mesiobuccal root (p = 0,046) in proximity with the sinus floor. The posterior teeth roots relationship with the maxillary sinus floor is better depicted and accurate by cone beam computed tomography images that may collaborated for a diagnosis and treatment planning that reduces the risks.
168

Avaliação tomográfica da pneumatização dos seios maxilares em regiões de perdas dentárias unitárias: estudo retrospectivo / Tomographic evaluation of maxillary sinus floor pneumatization in regions of single tooth loss: a cross-sectional study

Marília Cabral Cavalcanti de Morais Guerra 12 July 2017 (has links)
A perda dentária tem como consequência a atrofia óssea. Além disso, em regiões posteriores da maxila, a pneumatização do assoalho do seio maxilar (ASM) pode comprometer a instalação de implantes dentários em uma posição protética ideal. O objetivo deste estudo foi avaliar em imagens de tomografia computadorizada de feixe cônico (TCFC) a estimativa da pneumatização (EP) do ASM após perda dentária unitária em região posterior da maxila. 183 imagens de TCFC foram analisadas bilateralmente e divididas em 2 grupos: lado edêntulo (LE) - região edêntula unitária em segundo pré-molar, primeiro ou segundo molares superiores; lado dentado (LD) - região contralateral homóloga à região do LE, com dente presente. Os seguintes parâmetros foram avaliados para comparação LE versus LD: altura do seio (AS), desfecho primário, e área do seio maxilar (SM). A EP (diferença de AS do LE menos LD) e a altura do rebordo (AR - analisada apenas no LE) foram comparadas de acordo com tipo de dente e presença de pneumatização entre as raízes (PR) do LD. Além disso, o rebordo cicatrizado foi categorizado de acordo com a opção terapêutica para maxilar posterior. Os resultados mostraram que o LE apresentou a AS maior que o LD (p<0,05) (6,90 ± 3,15 mm e 6,0 ± 3,01 mm, para LE e LD respectivamente e a EP de 0,9 ± 2,93 mm). Ao separar EP por tipo de dente observou-se que os segundos pré-molares e segundos molares apresentaram valores próximos (1,36 ± 2,43 e 1,21 ± 2,98 mm, respectivamente), enquanto que os primeiros molares apresentaram valores menores (0,55 ± 3,03 mm) (p>0,05). Ao separar os dados de EP de acordo com a presença da pneumatização no LD, observou-se que a maioria dos dentes com esta condição foram os primeiros molares (36 em 43). A EP na presença dessa condição foi de -0,26 ± 2,82 mm, enquanto que na ausência de PR, a EP foi de 1,22 ± 2,99 (p<0,05). Em relação aos parâmetros da crista alveolar, o rebordo cicatrizado apresentou menor altura que às cristas alveolares palatina e vestibular. 54% dos casos de molares que apresentaram pneumatização entre as raízes obtiveram AR < 5mm, sugerindo necessidade de enxerto para uma futura instalação de implante dentário. Portanto, podemos concluir que perdas dentárias em região posterior de maxila favorecem a pneumatização do ASM e que esta varia de acordo com o tipo de dente. Além disso, a identificação de pneumatização entre as raízes parece indicar uma maior tendência à necessidade de cirurgias de levantamento de seio. / The aim of this study was to evaluate the estimation of MSF pneumatization (EP) after single tooth loss in the posterior maxilla region in cone beam computed tomography (CBCT) images. 183 CBCT images were analyzed bilaterally and divided into 2 groups: edentulous side (ES) - edentulous single region in the maxillary second premolar, first or second molars; Tooth side (TS) - contralateral region homologous to the ES region, with tooth present. The following parameters were evaluated for ES vs TS: sinus height (SH), primary outcome, and maxillary sinus area (MSA). The EP (SH difference between ES and TS) and ridge height (RH - analyzed only in ES) were compared according to tooth type and the presence of pneumatization between roots (PR) in TS. In addition, the healed ridge was categorized according to the therapeutic option for posterior maxilla. The results showed that the ES presented a higher SH than the TS (p <0.001) (6.90 ± 3.15 mm and 6.0 ± 3.01 mm for ES and TS respectively, and the EP of 0.9 ± 2.93 mm). When separating EP by tooth type, it was observed that the second premolars and second molars presented close values (1.36 ± 2.43 and 1.21 ± 2.98 mm, respectively), whereas the first molars presented minor values (0.55 ± 3.03 mm) (p>0.001). When separating the PR data according to the presence of pneumatization in the TS, it was observed that the majority of the teeth with this condition were the first molars (36 in 43). PE in the presence of this condition was -0.26 ± 2.82 mm, whereas in the absence of PR, the PE was 1.22 ± 2.99 (p <0.001). Regarding the parameters of the alveolar ridge, the healed ridge presented lower height than the palatal and vestibular alveolar ridges. 54% of the cases of molars that presented pneumatization between the roots obtained RH < 5mm, suggesting the need of grafting for a future installation of dental implant. Therefore, we can conclude that tooth loss in the maxillary posterior region favors the pneumatization of the MSF and it varies according to the type of tooth. In addition, the identification of pneumatization between the roots seems to indicate a greater tendency to the need for sinus lift surgeries.
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Identificação humana através da análise do seio maxilar em radiografias panorâmicas / Human identification by maxillary sinus in panoramic dental radiograph

Jamilly de Oliveira Musse 18 June 2009 (has links)
Os seios maxilares podem fornecer subsídios de real valor para a identificação forense. A individualidade dos contornos dos seios permite uma análise precisa, minuciosa, diminuindo os riscos de erros durante a atuação do perito. Os objetivos deste estudo foram: avaliar a possibilidade de investigação do sexo e identificação humana individual, pelos seios maxilares e propor três métodos de identificação através das referidas estruturas. A amostra foi composta por 656 radiografias panorâmicas de 328 indivíduos, com idade superior a 20 anos, de ambos os sexos, sendo estes divididos em grupo controle e experimental, de acordo com a ausência ou presença de perda dentária. De cada indivíduo foram utilizadas duas radiografias, uma inicial e outra após dois anos de tratamento ortodôntico. Três métodos foram empregados: dois manuais e um computadorizado. Nas técnicas manuais calculouse a altura e largura dos seios maxilares, em folhas de acetato e realizou-se a análise da morfologia dessas estruturas, por quadrantes. Na computadorizada, foi calculado a área, perímetro e fator de forma dos seios, através do programa IMAGELAB 2000®. A análise das variáveis quantitativas foi realizada empregando técnicas da estatística descritiva (média e desvio padrão), o teste t-Student com variâncias iguais ou desiguais e t-Student pareado. A comparação da morfologia dos seios nas radiografias do mesmo indivíduo foi feita através da observação visual dos quadrantes. Os métodos propostos para análise dos seios maxilares mostraram que a comparação da morfologia e mensurações destas estruturas em radiografias panorâmicas pode ser utilizada para estimativa do sexo e identificação humana individual. A perda dentária no grupo experimental não interferiu na dimensão dos seios maxilares. A incorporação da análise dos seios maxilares associada a outras evidências é passível de ser empregada nos Institutos Médico-Legais, podendo contribuir de forma significativa em casos de identificação humana. / The maxillaries sinus can supply real value subsidies for the forensic identification. The sinus outlines individuality allows an accuracy and meticulous analysis, reducing the mistakes risks during the expert performance. The aims of this study were: to evaluate the possibility of sex estimate and individual human identification for the maxillaries sinus and to propose three identification methods through referred structures. The sample was composed by 656 panoramic dental radiographs of 328 individuals with 20 years superior age, masculine and feminine. They were divided in controls and experimental groups, in agreement with the absence and presence of dental loss. It was used two radiographs of participants, an initial and other after two years of the orthodontic treatment. Three methods were used: two manual and one computerized. In the manual techniques it was calculated the height and width of the maxillaries sinus, in acetate and took place analysis of those structures morphology, for quadrants. In the computerized it was calculated the area, perimeter and factor in way of the sinus, through the IMAGELAB 2000® software. In the analysis of the results, the descriptive statistics were used (average and standard deviation) and the t-Student test with variances same or unequal and pared t-Student, for the quantitative variables and visual observation of the quadrants morphology of each maxillary sinus. The methods proposed for analysis of the maxillaries sinus showed that the morphology comparison and measurements of these structures in panoramic dental radiographs can be used to estimate of the sex and individual human identification. The dental loss in the experimental group didn\'t implicate in the dimension of the sinus maxillaries. The incorporation of the sinus maxillaries analysis associated to other evidences is susceptible to be used at the Forensic Institutes, could contribute in a significant way in human identification cases.
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Avaliação do seio maxilar por meio de tomografia computadorizada de feixe cônico / Maxillary sinus evaluation through Cone Beam Computed Tomography

Pagin, Otávio 26 May 2011 (has links)
O cirurgião-dentista necessita muitas vezes visualizar imagens associadas a estruturas importantes onde um bom conhecimento da anatomia crânio facial e dentomaxilar é imprescindível na elaboração de um diagnóstico correto. O seio maxilar é uma estrutura anatômica localizada no terço médio da face, sendo de extrema importância por estar localizado muito próximo às estruturas dentárias posteriores, devendo fazer parte do conhecimento dos cirurgiões-dentistas, nas diversas especialidades. Nesse estudo foram avaliados 50 exames de Tomografia Computadorizada de Feixe Cônico (TCFC) onde os seios maxilares podiam ser visualizados, resultando em um total de 78 extensões para diferentes regiões foram encontradas, 17 indivíduos apresentavam espessamento da membrana sinusal, 14 mostravam imagens compatíveis com cistos de retenção de muco e 6 apresentavam velamento do seio maxilar, variando entre total e parcial. Um total de 64 septos foram identificados no interior da cavidade sinusal, 86 cúpulas alveolares localizadas nas raízes dos diferentes dentes, 126 raízes foram encontradas em íntimo contato com o assoalho sinusal. Os resultados foram estatisticamente significantes para a relação entre cúpulas alveolares e extensões alveolares para a raiz palatina do dente 26, a presença de septos no teto dos seios maxilares de mulheres e da relação da média da região desdentada do dente 26 para os homens, com os valores de p < 0,05. Diversos fatores relacionados à morfologia do osso maxilar, a ausência de dentes e a própria conformação da cavidade sinusal podem resultar em diferentes formatos entre indivíduos e variações até no mesmo indivíduo. O exame por Tomografia Computadorizada de Feixe Cônico (TCFC) dos seios maxilares permite uma avaliação tridimensional e sua relação com as estruturas adjacentes, ou seja, uma perfeita reprodução da região dentomaxilofacial, auxiliando de maneira precisa os profissionais que irão intervir junto ou próximo a essa estrutura anatômica. / Dentistry professionals are required to analyze, in many cases, images associated to important structures where a great knowledge of the dentomaxillofacial anatomy is vital for an accurate diagnostic. The maxillary sinus is an anatomical structure that occupies the upper 2/3s of the maxillary bone and it is very important because the proximity with the posterior dental structures, it must be well known by dentists in the several specialties. In this study, 50 Cone Beam Computed Tomography (CBCT) exams in which the maxillary sinus could be evaluated, showed a total of 78 extension toward different regions were achieved, 17 subjects displayed a mucosal thickening, 14 evidenced a compatible imaging of mucous retention cysts and 6 presented a partially or completely filled maxillary sinus. A total of 64 maxillary sinus septa were identified, 86 different roots were localized inside de sinus, 126 roots were found to be in proximity with the sinus floor. The results were statistically significant to the relation made between these roots, which were inside the sinus and the alveolar extensions to the palatine root of the tooth 26, the presence of maxillary sinus septa located in the roof of the women maxillary sinus and the relation made between the median value for men in the edentulous region of the tooth 26, with a p value < 0,05. Its anatomy is one of the most varied, and many factors related to the maxillary bone morphology like edentulousness and the sinus conformation can result on different shapes, even in the same person. The Cone Beam Computed Tomography (CBCT) of the maxillary sinus provides a three-dimensional evaluation and its relationship with the boundary structures. It is a precise reproduction of the dentomaxillofacial region, providing valuable support to the professional who will work on or next to this anatomical structure.

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