Zirconia-based dental crown to support a removable partial denture: a three-dimensional finite element analysis using contact elements and micro-CT data

Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (μCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core - MAu; zirconia core - MZi) and the quality of the veneer/core interface (complete bonded - MZi; incomplete bonded - MZi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σmax) and von Mises equivalent (σvM) stresses were obtained. The σmax (MPa) for the bonded condition was similar between gold and zirconia cores (MAu, 0.42; MZi, 0.40). The incomplete bonded condition (MZi-NL) raised σmax in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σvM increased up to 270% in the MZi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface.

Construção de telescópio didático para divulgação científica

This research is dedicated at those who think about the importance of science teatching as a way to contribute to the transformation and innovation of science, attracting people and demystifying concepts, the main objective of this research is the demonstratation step by step the complete process to manufacture of didactic Newtonian telescope, discussing in detail all the processes involved .Adittionally, it has been shown that the proposed instrument it can be aplied in and promote the popular access to scientific knowledge

Ensino de física e energia: estudo de possibilidades didáticas na educação básica

This monograph has the inspiring theme of the Energy education, concept of extreme importance to physics, but that is rarely addressed in Brazilian schools. We bring a discussion of the problems faced in teaching this subject and present this analysis of how this issue is addressed in some textbooks that are part of the material available to students of basic education in our country. We also discuss a didactic proposal to the Physics Teaching using for this experiment. The proposal considers the student protagonist of the learning process being the builder of his own knowledge. For this proposal selected three experiments (solar plate, looping and looping coffee cups) analyzed from the point of view of energy that have the intention to leave this clearer content and close to the students. Here is the end of this work the application of the examination of this proposal in a public school in full-time education in the municipality of Rio Claro - SP

Física e música: o uso de canções como ferramenta auxiliar no ensino de física

In this work we present a didactic proposal to use song lyrics for Physics Teaching aimed to High School level. Based on the work proposed by Zanetic (1990) that Physics is also Culture, we understand that its influence extends beyond the scientific boundaries, reaching spheres of knowledge where its presence is less obvious, such as the arts, especially Music. Based on proposals for Ramos and Gomes (2013), activities were conducted in two groups of second year of high school in the city of Rio Claro, each with an approach. In one of the classes the students received as material the lyrics of the songs printed and the other students were given a table along with the lyrics. In these materials the students identified physical concepts present in the songs Nuclear Shelter of the São Paulo band Premeditando the Breque and Manhattan Project of the Canadian band Rush. We observed during activities an improvement in the participation of students in theoretical discussions, probably due to a more favorable context for students to express themselves assigned by us to the activities with the songs. After performing the activities we demonstrated that you can enter the Music in the classroom not only as entertainment but as an aid in research and understanding of physical concepts

O ensino de física e a curiosidade epistemológica: o uso de experimentos de eletricidade em atividades educacionais

We analyzed with this work the importance of using experiments in the classroom, especially the low-cost experiments for better learning of Physics, discussing the context where this discipline is inserted, which in general, has been presented to students in a traditional, mechanistic way. We worked with the electrostatic theme and low cost didactic experiments, focusing on the pizza electrophorus. About the handling of this experiment, we can see the surprise and curiosity in students, depending on how it is used in didactic activities in order to make it meaningful to the student. We discussed how the curiosity can be harnessed in the classroom, the types of curiosity according to Freire, how to overcome the curiosity to become epistemological, the physics involved in the experiment and the teacher's role in this context

Uma abordagem didático-pedagógica do cálculo diferencial e integral I na formação de professores de matemática

Pós-graduação em Educação Matemática - IGCE

Lógica Fuzzy aplicada à geologia

Pós-graduação em Matemática em Rede Nacional - IBILCE

Concepções e práticas do ensino de leitura em inglês no ensino médio

Pós-graduação em Educação Escolar - FCLAR

O livro didático e o ensino de História em uma escola pública situada no interior paulista

Pós-graduação em Docência para a Educação Básica - FC

Delayed tooth replantation after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals difference (p > 0.05) was found among the groups regarding the areas difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the delayed rat tooth replantation.

Delayed tooth repalantetion after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was done after 60 min. In Group II, the root canals were filled with a calcium hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for 3 min, the canals were filled with calcium hydroxide and the teeth were replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals were sacrificed 60 days postoperatively. Results: Regarding replacement resorption, there was statistically significant difference (p < 0.05) between the control group and the other three groups. No statistically significant difference (p > 0.05) was found among the groups regarding the areas of inflammatory resorption. There was also a statistically significant difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV compared to the Groups II and III, but this difference was not significant statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the occurrence of ankylosis, root resorption and inflammatory resorption in delayed rat tooth replantation.

Percepción de estudiantes de odontología sobre educación a distancia

Introduction: distance education is defined as a learning mode in which pedagogical and didactic mediation in teaching and learning processes is characterized by the use of information and communication means and technology by both teachers and students, and the development of educational activities at different settings and technologyand. Objective: evaluate the knowledge obtained by students from the last year of Odontology about distance education and their opinions about the subject. Methods: across-sectional descriptive exploratory study was conducted. Of the total 140 university students, 120 participated in the study. A self-applied questionnaire was developed with questions related to the student, the use of the Internet and distance education. The professional updating alternatives included were graduate courses and subscription to newspapers. Results: 29.2 % of the students use the Internet on a daily basis; only one student stated that he did not use the Internet. Of the students interviewed, 63.34 % did not know any form of distance education. As a consequence, 97.5 % had never taken part in a distance education course and 62.5 % stated that they did not know whether they would. Conclusions: results show that odontology students are prejudiced against nontraditional learning modes, though they use the Internet on a regular basis. Despite the existence of legislation regulating distance education, students are still concerned about its quality and legality.

Um estudo da geometria projetiva elíptica

Pós-graduação em Matemática Universitária - IGCE

O mirabolante mundo das partículas elementares: uma sequência didática para professores de física

Pós-graduação em Ensino de Física (mestrado profissional) - FCT

O jogo de escopa adaptado para o uso em sala de aula

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)