RESUMO
<p><b>OBJECTIVE</b>The effect of sandblasting on the bond strength between 3mol% yttrium-stabilized tetragonal zirconium polycrystal (3Y-TZP) zirconia framework and veneering porcelain was evaluated.</p><p><b>METHODS</b>A total of 21 specimens [(25 ± 1) mm x (3 ± 0.1) mmx (0.5 ± 0.05) mm] were prepared according to ISO 9693. The specimens were then randomly divided into 3 groups. Sandblasting was performed on 2 meshes of Al₂O₃ particles: group A with mesh 110 and group B with mesh 80. Group C, which was not sandblasted, was the control group. The surface roughness of the zirconia framework, as well as the bond strength between 3Y-TZP zirconia framework and veneering porcelain, was measured. The interface microstructure was observed by scanning electron microscope (SEM), and elemental distribution was detected by energy dispersive spectroscopy (EDS).</p><p><b>RESULTS</b>Surface roughness values were (1.272 ± 0.149) μm for group A, (0.622 ± 0.113) μm for group B, and (0.221 ± 0.065) μm for group C. Statistical significance were found among groups (P < 0.05). The bond strength values were (28.21 ± 1.52) MPa for group A, (27.71 ± 1.27) MPa for group B, and (24.87 ± 3.84) MPa for group C. Statistical significance was found between group A and group C (P < 0.05), whereas the other groups had no statistical significance (P > 0.05). Interface adhesion failure was the primary performance. SEM images showed the close interface bonding, and EDS showed that the interface had no obvious element penetration.</p><p><b>CONCLUSION</b>Al₂O₃ sandblasting can slightly enhance the bond strength between zirconia framework and veneering porcelain.</p>
Assuntos
Óxido de Alumínio , Química , Colagem Dentária , Porcelana Dentária , Química , Análise do Estresse Dentário , Facetas Dentárias , Teste de Materiais , Microscopia Eletrônica de Varredura , Resistência ao Cisalhamento , Propriedades de Superfície , Ítrio , Química , Zircônio , QuímicaRESUMO
In order to improve students' overall quality,Biomedical Engineering College of Chongqing Medical University has carried out quality development training in the 6 session of the 450 students.The content includes development projects,the queue training,humanities lectures,inspirational film etc.; the objective is to develop the students' mind,develop their team spirit and interpersonal communication skills.College has recruited and assisted professional instructors in the whole training.The centralized training in specific situations gives students a strong spiritual shock and strong positive energy.Before and after the training we use the same questionnaire to students,the results of which have shown that their comprehensive ability,EQ,and cohesion of the class have been improved.
RESUMO
This paper discussed on the innovative efforts of establishing production-teaching-research platform and multi-channel international cooperation model by Chongqing Medical University. Measures taken included offering theoretical courses across the first-level disciplines of medicine and engineering and encouraging research tasks that involve the cooperation among hospitals , businesses and universities, creating education environment for postgraduates combing medicine and engineering and launching the cultivation of biomedical engineering postgraduates. The aim of these measures was to incorporate the achievements of scientific research innovation into postgraduate education and to improve its quality.
RESUMO
<p><b>OBJECTIVE</b>To investigate the microstructure of dental zirconia ceramics prepared by two-step sintering.</p><p><b>METHODS</b>Nanostructured zirconia powder was dry compacted, cold isostatic pressed, and pre-sintered. The pre-sintered discs were cut processed into samples. Conventional sintering, single-step sintering, and two-step sintering were carried out, and density and grain size of the samples were measured. Afterward, T1 and/or T2 of two-step sintering ranges were measured. Effects on microstructure of different routes, which consisted of two-step sintering and conventional sintering were discussed. The influence of T1 and/or T2 on density and grain size were analyzed as well.</p><p><b>RESULTS</b>The range of T1 was between 1450 degrees C and 1550 degrees C, and the range of T2 was between 1250 degrees C and 1350 degrees C. Compared with conventional sintering, finer microstructure of higher density and smaller grain could be obtained by two-step sintering. Grain growth was dependent on T1, whereas density was not much related with T1. However, density was dependent on T2, and grain size was minimally influenced.</p><p><b>CONCLUSION</b>Two-step sintering could ensure a sintering body with high density and small grain, which is good for optimizing the microstructure of dental zirconia ceramics.</p>
Assuntos
Cerâmica , ZircônioRESUMO
Principles of medical equipment course were explored of formative evaluation as the center examination,constructed an examination reform scheme as” One center (formative evaluation as the center),three systems (content system,operation system,monitoring system).” Made students to learn from the center of focus scores change to autonomous learning and culture analysis,solves the question ability and practical ability.At the same time,strengthen the teaching process of teaching and learning to communicate and exchange,Get the students learning feedback information to improve teaching and learning in time,Strengthen the students′ ability of autonomous learning and lifelong learning ability.
RESUMO
Medical treatment technology has made a lot of breakthrough because of the rapid development of the medical devices industrial.Minimally-invasive and noninvasive medicine is the development tendency of the future medicine.To adapt to the needs of the future medicine,Chongqing medical university exerted much efforts on training of minimally-invasive and noninvasive medical talents.We explored and practiced in aspects of fixing educational conception and goal,building curriculum and teaching content,constructing professional teaching team and developing practice and innovation abilities in order to fill the void of personnel training in the minimally-invasive and noninvasive medical field.
RESUMO
To implement the‘student-oriented'concepL we need to implement it into the practical of educational reformation,believe the academic ability and great potential of students and actively create conditions for the development of students,reform training model and formulate training plan based on social needs and employment,adopt various methods to train the autonomic learning ability and innovative consciousness of students,and allow students to participate in the teaching management so as to fully develope the subjective role of students in the teaching and learning process.
RESUMO
According to the investigation result in 398 students of the College of Pharmacy of Chongqing Medical University on study motivation,atitude,extracurricular study time and study method,the entire status of study attitude in pharmacutical students and the effect of study motivation,attitude,grade diversity and gender difference on learning were analyzed.It is indicated that the pharmacutical students in medical university are a group with a certain speciality.Therefore,in order to improve the educational quality of pharmacy,the teaching and students affairs should be developed with clear target.
RESUMO
To strongly promote the activity of reading classics among medical students, Chongqing University of Medical Sciences has made a sampling survey on the state of reading and their literature knowledge among the medical students. The survey shows that the medical students agree to the necessity and probability of reading classics, that they also show some obvious preferences for interest in reading and that there is a huge difference in hierarchy,grade and sex with regard to the grasp of literature, history, philosophy, arts and technology for medical students. The outcome of this survey will undoubtedly make a great revelation on how to carry out the activity of reading classics.