135 research outputs found
Influência dos filtros de pós-processamento de imagens radiográficas digitais na avaliação da altura da crista óssea alveolar
Benefits of using a photostimulable phosphor plate protective device
Objectives: To develop and test a protective device (PD) to increase the resistance of photostimulable storage phosphor (PSP) plate to compressive load, and assess the resulting image quality. Methods: Two prototypes, polyvinylchloride sheets of 0.3 mm and 0.7mm each, were developed for PSP plate size 2. The resistance to compressive load was tested using eight new PSPs divided into four test groups: (1) PSP, (2) PSP and paperboard protector, (3) PSP and 0.3 mm PD, and (4) PSP and 0.7 mm PD. The resulting images were analyzed by three oral radiologists, based on the consensus for image artifacts. Additionally, the objective image quality test was performed with four new PSPs, using an 8-step wedge aluminum scale. The mean gray values and standard deviation were measured in a total of 240 images, and the data were analyzed using analysis of variance with Bonferroni post-hoc test. Results: Artifacts were seen in the PSP control group starting at 40n, and at 150n, 175n and 300n in 0.3 mm PD, paperboard protector and 0.7mm PD, respectively. Although there was no statistical difference among groups, there were differences between exposure times (0.06– 0.25s, 0.06–0.40s, and 0.10–0.40 s). Scanning resolution of 20 lp/mm showed higher mean gray value than 25 and 40 lp/mm (p < 0.05) Conclusion: The developed PDs improved the PSP resistance to compressive forces, with low interference on the pixel gray values, regardless of exposure time and spatial resolution. Nevertheless, the 0.7 mm PD could withstand the maximum compressive load
Does clinical experience impact students’ capacity to diagnose dentoalveolar disorders using intraoral radiography?
Introdução: O domÃnio da interpretação radiográfica contribui para o correto diagnóstico de alterações do complexo dento-alveolar, e seu aprimoramento durante o perÃodo da graduação é essencial. No momento em que se inicia a carreira profissional fora da faculdade, é esperado que o conhecimento teórico adquirido, associado à experiência clÃnica durante a graduação, melhore a performance diagnóstica do dentista. Objetivo: Esse estudo objetivou avaliar diagnósticos feitos a partir de exames radiográficos intrabucais, realizados por alunos de graduação de uma faculdade de odontologia do sul do Brasil, antes e após a sua introdução na prática clÃnica. Materiais e métodos: Para tal, diagnósticos de radiografias interproximais e periapicais, feitos durantes o Segundo ano (T0) e Quarto ano (T1) do curso de graduação, foram avaliados. Uma análise descritiva foi expressa e o teste de McNemar foi realizado para comparar as respostas em T0 e T1. Resultados: Quinze alunos completaram os dois questionários. De uma forma geral, a porcentagem de respostas corretas em T0 foi de 70.5%, e em T1 foi de 61.6%, com uma diferença significativa entre elas (p = 0.024). Discussão: Este estudo salienta a necessidade de estratégias educacionais que melhorem a competência diagnóstica durante as atividades clÃnicas da graduação, uma vez que exames radiográficos são essenciais em todas as áreas da odontologia. Conclusão: Neste estudo, o correto diagnóstico de alterações dentoalveolares a partir de radiografias intraorais apresentou um redução significativa após os primeiros anos de prática clÃnica.Mastery of interpretation of radiographic images is a contributing factor in correct diagnosis of conditions affecting the dentoalveolar apparatus. It is therefore essential that students’ perfect these skills while studying for their degrees. Once they embark upon their professional careers outside of the university setting, it is expected that the theoretical knowledge and clinical experience accumulated during the course of their studies will have led to improved diagnostic performance. Objective: The objective of this study was to evaluate diagnoses made using intraoral radiographs by undergraduate students at a School of Dentistry in the South of Brazil, before and after their introduction to clinical practice. Materials and methods: Diagnoses made during the second (T0) and fourth (T1) years of the undergraduate course in dentistry using interproximal and periapical radiographs were analyzed. Descriptive statistics were calculated and the McNemar test was used to compare answers at T0 and T1. Results: Fifteen students answered questionnaires at both T0 and T1. The overall percentage of correct answers was 70.5% at T0 and 61.6% at T1, with a significant difference (p = 0.024). Discussion: This study highlights the need for educational strategies that improve diagnostic competence during undergraduate clinical activities, since radiographic examinations are essential in all areas of dentistry. Conclusions: Therefore, it was concluded that the rate of correct diagnosis of dentoalveolar disorders by intraoral radiography decreased significantly after the initial years of clinical training
Exploring digital filters for internal root resorption : how can we improve the diagnosis of small lesions?
Objectives: This study aimed to evaluate the impact of enhancement filters in detecting small simulated internal root resorptions (IRR). Methods: Forty-two extracted human teeth were sectioned, connected, and stored in a dry human jaw and X-rayed with photostimulable phosphor plates (PSPs), composing the control group (CG). In the middle-third of the root canals, IRR lesions were simulated using Da Silveira protocol. Later, the specimens were X-rayed to create the test group (TG). All images acquired were exported with seven enhancement filters plus the original image. Three examiners used a five-point Likert scale to evaluate the images regarding the presence/absence of IRR. Diagnostic efficacy was assessed from sensitivity and specificity results. Comparison among filters was performed by using receiver operating characteristic (ROC) curve analysis. Results: Moderate values of Kappa interexaminer (0.403–0.620) and high values of Kappa intraexaminer (0.757–0.915) were observed. The best performance occurred in the CG (p < 0.05). Original images presented the greatest sensitivity and area under the ROC curve (0.595–0.750), while the Endo filter presented the greatest specificity (0.952). Inversion and Pseudo-3D images produced the greatest doubt in the diagnosis, significant for CG with the Pseudo-3D filter (p < 0.05). Conclusions: The Original and ‘Endo’ filters should be chosen as it offers greater diagnostic ability and allows more confidence during the evaluation
Monitorias na área da Radiologia Odontológica: vivências durante o perÃodo de ensino presencial e do ERE
Impacto da identificação do ponto anatômico e do erro padrão de mensuração na análise cefalométrica utilizando um modelo de simulação matemática
Objective: To assess, using a mathematical simulation model, the participation of each coordinate involved in the formation of cephalometric angles and to determine the extent to which errors in the identification of cephalometric landmarks can, individually and collectively, influence the measurement of these angles. Material and Methods: The reference values and standard errors of 13 landmarks obtained from the analysis of 30 cephalograms were used. For each landmark, 1000 observations were simulated using the Monte Carlo method. On the basis of linear regression models, equations designed to estimate measurement errors due to landmark identification errors were obtained and analysed. Results: The coordinates most involved in the formation of the angles SNA, SNB, ANB, FMA, PPL, DFC, and AEF were Ny, Ny, Ax, Goy, Poy, Poy, and Ptmx, respectively, and the standard measurement errors for these angles were 1.2, 0.9, 0.8, 1.6, 1.5, 1.5, and 1.4, respectively. Conclusion: The standard measurement error of the angle depends on the geometric impact coefficient and the standard error of the coordinates involved in the formation of the angles, and the geometric impact coefficient varies according to the angle analysed.Objetivos: Avaliar, empregando um modelo matemático de simulação, a participação de cada coordenada envolvida na formação de ângulos cefalométricos, assim como determinar a extensão da influência dos erros na identificação dos pontos cefalométricos, individual e coletivamente, na mensuração destes ângulos. Materiais e métodos: Foram utilizados os valores de referência e os erros padrão de 13 pontos anatômicos obtidos a partir da análise de 30 cefalogramas. Para cada ponto anatômico, foram simuladas 1000 observações utilizando o método de Monte Carlo. Com base em modelos de regressão linear, foram obtidas e analisadas equações destinadas a estimar os erros de medição devido a erros na identificação dos pontos cefalométricos. Resultados: As coordenadas mais envolvidas na formação dos ângulos SNA, SNB, ANB, FMA, PPL, DFC, e AEF foram Ny, Ny, Ax, Goy, Poy, Poy, e Ptmx, respectivamente, e os erros padrão de mensuração destes ângulos foram 1,2; 0,9; 0,8; 1,6; 1,5; 1,5 e 1,4, respectivamente. Conclusões: O erro padrão de mensuração de cada ângulo cefalométrico depende do coeficiente de impacto geométrico e do erro padrão das coordenadas dos pontos anatômicos envolvidos na formação dos mesmos, sendo que o coeficiente de impacto geométrico varia de acordo com o ângulo analisado
Implementação do sistema digital intrabucal na Faculdade de Odontologia da UFRGS: a participação ativa dos bolsistas PAG
Comparação das repetições de radiografias intrabucais digitais realizadas por alunos da Extensão em Radiologia e da ClÃnica Odontológica II
- …