ABSTRACT
OBJECTIVES: To assess the distortion of high-density materials using two CBCT devices presenting convex triangular and cylindrical fields of view (FOVs). METHODS AND MATERIALS: Four high-density cylinders were individually placed in a polymethylmethacrylate phantom. 192 CBCT scans were acquired using the convex triangular and cylindrical FOVs of Veraviewepocs® R100 (R100) and Veraview® X800 (X800) devices. Using HorosTM's software, two oral radiologists determined the cylinders' horizontal and vertical dimensional alterations. Nine oral radiologists subjectively identified each cylinder's axial shape distortion. Statistical analysis comprised Multiway ANOVA (α = 5%), and the Kruskal-Wallis test. RESULTS: The distortion in the axial plane was greater in the convex triangular FOVs for both devices in almost all the materials (p < 0.05). The evaluators subjectively identified a shape distortion in both FOVs for R100 device (p < 0.001), while no distortion was identified for X800 device (p = 0.620). A vertical magnification of all materials was observed in both FOVs for both devices (p < 0.05). No differences among vertical regions (p = 0.988) nor FOVs (p = 0.544) were found for the R100 device, while all materials showed higher magnification in all regions in the cylindrical FOV (p < 0.001) of the X800 device. CONCLUSIONS: The convex triangular FOV influenced the axial distortion of the high-density materials in both devices. A vertical magnification was observed in both FOVs of both devices, but it was greater in the cylindrical FOV of the X800 device.
Subject(s)
Cone-Beam Computed Tomography , Humans , Cone-Beam Computed Tomography/methods , Phantoms, ImagingABSTRACT
Na presente pesquisa propôs-se avaliar a opinião de estudantes de Odontologia quanto à experiência vivenciada mediante aplicação da aprendizagem baseada em problemas (Problem-Based Learning - PBL) na disciplina de Radiologia Odontológica. A amostra foi composta por 138 estudantes de uma instituição de ensino privada, sendo a maior parte do gênero feminino (75,20%, n = 104). Houve predomínio da faixa etária de 19 a 20 anos (39,59%, n = 56), de estudantes oriundos de escolas públicas (62,19%, n = 86) e com renda familiar mensal entre R$ 4.501,00 e R$ 9.500,00 (22,79%; n = 32). Quando questionados sobre o método PBL, um total de 127 (92,00%) considerava válida a experiência com novos métodos de ensino-aprendizagem e 129 (93,53%) não o conheciam. Ainda, 123 (89,05%) acreditavam que a timidez pode atrapalhar o estudante no método PBL e 113 (82,14%) concordavam que o professor tem uma participação discreta nessa metodologia de ensino. Após a avaliação, 108 estudantes (78,49%) não se mostraram satisfeitos com a nota atribuída e 105 (76,38%) não gostariam de estudar em uma Instituição na qual todas as disciplinas utilizassem o PBL. Concluiu-se que os estudantes participantes deste estudo apresentaram dificuldades com o método PBL e não estiveram plenamente satisfeitos quando participaram de atividades nesse formato. Acredita-se que esses achados possam ser explicados pelas peculiaridades de abordagem dos conteúdos e critérios de avaliação que envolvem habilidades e competências, indicadores que vão além do conhecimento cognitivo e com os quais os estudantes não estão habituados (AU).
The aim of this study was to evaluate the opinion of dental students about their experience with the problem-based learning (PBL) method in the Dental Radiology discipline. A total of 138 students participated in this study, out of which 104 were females (75.20%). The sample was mostly composed of students between 19-20 years old (39.59%, n = 56) from public schools (62.19%, n = 86) and with monthly income between R$ 4,501.00 and R$ 9,500.00 (22.79%, n = 32). When they were asked about the PBL method, 127 (92.00%) considered positive the experience with new teaching-learning methods and 129 (93.53%) were not aware of the PBL method. The results also showed that 123 students (89.05%) believed that shyness can negatively affect learning in the PBL method and 113 (82.14%) agreed that the professor has a discrete role. After the exams, 108 students (78.49%) were not satisfied with their grade and 105 (76.38%) would not appreciate to study in an institution in which the PBL was applied in all disciplines. As a conclusion, the students who participated in this study had difficulties with the PBL method and were not fully satisfied when participating in activities with such a format. These findings can be explained by the particular approach of the contents in the PBL method, further the evaluation criteria involving skills and competencies. These are indicators that go beyond cognitive knowledge and which the students are not used to consider (AU).
