Determinação da resistência flexural de cimentos resinosos comerciais, com variação do sistema de ativação e tempo de armazenamento pós-ativação

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Odontologia.Este estudo investigou a resistência flexural de amostras confeccionadas com os cimentos resinosos duais Enforce, RelyX CRA e Variolink II submetidas à dupla ativação ou apenas à ativação química, aos trinta minutos e vinte e quatro horas após o início da polimerização. O cimento Enforce apresentou os valores mais altos de resistência flexural, independentemente do tipo de ativação e do tempo de armazenamento. No período de 30 minutos de armazenamento, não foram observadas significâncias estatísticas entre os materiais e a dupla ativação. Já, na polimerização química, o Enforce foi superior aos outros materiais testados neste mesmo tipo de polimerização. No período de 24 horas de armazenamento, não houve significâncias estatísticas na interação materiais x tipos de ativação

Clinical Reasoning in the Real World Is Mediated by Bounded Rationality: Implications for Diagnostic Clinical Practice Guidelines

Background: Little is known about the reasoning mechanisms used by physicians in decision-making and how this compares to diagnostic clinical practice guidelines. We explored the clinical reasoning process in a real life environment. Method: This is a qualitative study evaluating transcriptions of sixteen physicians' reasoning during appointments with patients, clinical discussions between specialists, and personal interviews with physicians affiliated to a hospital in Brazil. Results: Four main themes were identified: simple and robust heuristics, extensive use of social environment rationality, attempts to prove diagnostic and therapeutic hypothesis while refuting potential contradictions using positive test strategy, and reaching the saturation point. Physicians constantly attempted to prove their initial hypothesis while trying to refute any contradictions. While social environment rationality was the main factor in the determination of all steps of the clinical reasoning process, factors such as referral letters and number of contradictions associated with the initial hypothesis had influence on physicians' confidence and determination of the threshold to reach a final decision. Discussion: Physicians rely on simple heuristics associated with environmental factors. This model allows for robustness, simplicity, and cognitive energy saving. Since this model does not fit into current diagnostic clinical practice guidelines, we make some propositions to help its integration. Copyright: © 2010 Bonilauri Ferreira et al

Intraobserver and interobserver reproducibility of the old and new classifications of toracolombar fractures

ABSTRACT Objective: To evaluate the inter and intraobserver agreement of the Magerl AO and AOSpine thoracolumbar fracture classification systems. Methods: The participants were divided into two groups, the first composed of six spinal surgeons and the other composed of 18 medical orthopedic residents. On two different occasions, separated by an interval of one month, the participants analyzed and classified 25 radiographs with thoracolumbar fractures using both thoracolumbar fracture classification systems, Magerl AO and AOSpine. The results were analyzed for classification reliability using the Kappa coefficient (k). Results: The Magerl AO classification system showed a fair interobserver agreement (k = 0.32), considering the fractures type and subtype, whereas the AOSpine classification system showed a moderate interobserver agreement (k = 0.59). The Magerl AO classification showed a fair intraobserver agreement for both residents and specialists (k = 0.21 and 0.38, respectively), while the AOSpine showed a substantial agreement between residents (k = 0.62) and moderate between specialists (k = 0.53). Conclusions: When evaluating fracture morphology, the AOSpine thoracolumbar fracture classification system presented a better reliability and reproducibility compared to the Magerl AO classification system