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BACKGROUND: Since color measurements are relative, the discrepancy among different instruments is alarmingly high. This multicenter study evaluated the effectiveness of instrument calibration and inter-instrument harmonization of different spectrophotometers with the same optical geometry using tooth-colored, translucent dental materials. METHODS: The coordinating center (CC) spectrophotometer was calibrated using the NPL Ceram Series II set. Two sets of 10 specimens, labeled 1 to 10 and I to X (10 mm in diameter and 1 mm thick), were tested at CC and three research sites (RS1, RS2, and RS3) using the same d/8° optical geometry spectrophotometers. Calibration factors were calculated for each material and site to obtain the average calibration factors for sets 1-10, set I-X, and the combination of both. The differences among the non-corrected and corrected reflection values were calculated using CIEDE2000 (DeltaE00) and CIELAB (DeltaEab) color difference formulas and were submitted to ANOVA and Tukey test (α = 0.05). RESULTS: A significant decrease of color differences between non-corrected as compared to corrected measurements was recorded for all CC-RS and RS-RS comparisons. The reduction of DeltaE00 values between non-corrected and corrected for CC-RS1, CC-RS2, and CC-RS3 were 83.1%, 77.2%, and 73.6%, respectively. The corresponding DeltaE00 values for RS1-RS2, RS1-RS3, and RS2-RS3 comparisons, indirectly compared in the experiment, were 84.2%, 82.8%, and 68.5%, respectively. There was a significant reduction of DeltaE00 and DeltaEab color difference for all combined RS pairs and each of three RS pairs, corrected with one of two specimen sets calibration factors separately. CONCLUSIONS: Calibration and harmonization of color measurements in dentistry using tooth-colored, translucent restorative materials significantly decreased measurement discrepancies between the coordinating center and research sites and among pairs of research sites.

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Y-TZP/MWCNT-SiO2 nanocomposite was synthesized by co-precipitation and hydrothermal treatment methods. After the characterization of the MWCNT-SiO2 powder, specimens were obtained from the synthesized material Y-TZP/MWCNT-SiO2 by uniaxial pressing for a second characterization and later comparison of its optical and mechanical properties with the conventional Y-TZP. The MWCNT-SiO2 was presented in bundles of carbon nanotubes coated by silica (mean length: 5.10 ± 1.34 µm /D90: 6.9 µm). The composite manufactured was opaque (contrast ratio: 0.9929 ± 0.0012) and had a white color with a slightly difference from the conventional Y-TZP (ΔE00: 4.4 ± 2.2) color. The mechanical properties of Y-TZP/MWCNT-SiO2: vickers hardness (10.14 ± 1.27 GPa; p = 0.25) and fracture toughness (4.98 ± 0.30 MPa m1/2; p = 0.39), showed no significant difference from the conventional Y-TZP (hardness: 8.87 ± 0.89; fracture toughness: 4.98 ± 0.30 MPa m1/2). However, for flexural strength (p = 0.003), a lower value was obtained for Y-TZP/MWCNT-SiO2 (299.4 ± 30.5 MPa) when compared to the control Y-TZP (623.7 ± 108.8 MPa). The manufactured Y-TZP/MWCNT-SiO2 composite presented satisfactory optical properties, however the co-precipitation and hydrothermal treatment methods need to be optimized to avoid the formation of porosities and strong agglomerates, both from Y-TZP particles and MWCNT-SiO2 bundles, which lead to a significant decrease in the material flexural strength.

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Objective: The aim of this study was to compare the performance of day- and evening-class students in the first semester test of Dental Materials in the School of Dentistry at São José dos Campos - UNESP, who were exposed to traditional lectures (TRAD) and Team-Based Learning (TBL). Material and Methods: The results of Dental Materials first semester test of students, from day and evening classes of 2016 were tabulated and analyzed in this research. The groups formed for the execution of the methodology were randomized using the individual global average of the previous year of the students, and the groups were composed of 6 to 7 members, maintained throughout the course. During the correction of the tests, the subject of each question and the applied methodology (TBL and TRAD) were identified. Responses of each question were graded separately according to the subject for comparison between methodologies. A total of 88 tests were evaluated. The performance was evaluated through a comparison of the average grade of each question, related to a specific learning methodology. The data were submitted to t-test. Results: The students' overall performance was similar when both methodologies were compared. Students from day class presented higher grades with TBL whilst evening class students presented better performance in questions with traditional lectures. Conclusion: Active learning should be further implemented in Brazilian Dental Schools to change students' habits aiming to improve their personal and social skills besides of professional technical knowledge. (AU)

Objetivo: O objetivo deste estudo foi comparar o desempenho de alunos dos turnos diurno e noturno na prova do primeiro semestre da Disciplina Materiais Dentários da Faculdade de Odontologia de São José dos Campos - UNESP, expostos a aulas tradicionais (TRAD) e Aprendizagem Baseada em Equipe (TBL). Material e Métodos: Os resultados da prova dos alunos, dos turnos diurno e noturno de 2016, foram tabulados e analisados. As turmas utilizadas para a execução da pesquisa foram randomizadas utilizando-se a média global individual do ano anterior dos alunos, sendo as turmas compostas de 6 a 7 integrantes, mantidas ao longo do curso. Durante a correção das provas, foram identificados os assuntos de cada questão e a metodologia aplicada (TRAD e TBL). As respostas de cada questão foram graduadas separadamente de acordo com o assunto para comparação entre as metodologias. Um total de 88 testes foi avaliado. O desempenho dos alunos foi avaliado por meio da comparação da nota média de cada questão, relacionada a uma metodologia específica de aprendizagem. Os dados foram submetidos ao teste t. Resultados: O desempenho geral dos alunos foi semelhante quando comparadas as duas metodologias. Os alunos do período diurno apresentaram notas mais altas no tratamento TBL, enquanto os alunos do período noturno apresentaram melhor desempenho nas questões com aulas expositivas tradicionais. Conclusão: A aprendizagem ativa deve ser mais implementada nos cursos de graduação em Odontologia, no Brasil, para melhorar as habilidades pessoais e sociais dos alunos, além de aperfeiçoar o conhecimento técnico profissional dos discentes (AU).

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Objective: to evaluate the differentiation and gene expression of transcripts related to osteogenesis in a primary culture of Mesenchymal Stem Cells (MSCs) derived from rat femurs submitted to radiotherapy and the installation of pure titanium implants. Material and Methods: fifty-four rats received titanium implants in both femurs and were divided into three groups: Control: implant surgery (C); Implant + immediate irradiation (IrI), and Implant + late irradiation (IrL). Euthanasia occurred 3, 14, and 49 days after surgery. The bone marrow MSCs from the femurs were isolated and cultivated. The cell viability, total protein content, alkaline phosphatase (ALP) activity, and the formation of mineralization nodules and cellular genotoxicity were analyzed. The gene expression of Alkaline Phosphatase (phoA), Collagen 1 (COL1), Runt-related transcription factor 2 (RUNX2), Osterix (OSX), Osteopontin (OPN), Integrin ß1(ITGB1), Bone Sialoprotein (BSP), Osteonectin (SPARC), Osteocalcin (Bglap), Transforming Growth Factor ß-type (TGF-ß), Granulocyte Macrophage Colony Stimulating Factor (GM-CSF), Interleukin-6 (IL-6), Apolipoprotein E (APOE) and Prostaglandin E2 synthase (PGE2) were evaluated by qRT- PCR. Results: ionizing radiation suppresses the gene expression of essential transcripts for bone regeneration, as well as cellular viability, as observed in the IrI and IrL groups. Conclusion: although this can lead to the loss of osseointegration and failure of the implant, the MSCs showed more activity at 49 days than at 3 and 14 days. (AU)

Objetivo: avaliar a diferenciação e expressão gênica de transcritos relacionados à osteogênese em cultura primária de MSCs derivadas de fêmures de ratos submetidos à radioterapia e instalação de implantes de titânio puro. Material e Métodos: cinquenta e quatro ratos receberam implantes de titânio em ambos os fêmures e foram divididos em três grupos: Controle: cirurgia de implante (C); Implante + irradiação imediata (IrI) e Implante + irradiação tardia (IrL). A eutanásia ocorreu 3, 14 e 49 dias após a cirurgia. As MSCs de medula óssea dos fêmures foram isoladas e cultivadas. Foram analisadas a viabilidade celular, teor de proteína total, atividade da fosfatase alcalina (ALP), formação de nódulos de mineralização e genotoxicidade celular. A expressão gênica de Fosfatase Alcalina (phoA), Colágeno 1 (COL1), fator de transcrição relacionado a Runt 2 (RUNX2), Osterix (OSX), Osteopontina (OPN), Integrina ß1 (ITGB1), Sialoproteína Óssea (BSP), Osteonectina (SPARC), Osteocalcina (Bglap), Fator de Crescimento Transformador tipo ß (TGF-ß), Fator Estimulante de Colônia de Granulócitos-Macrófagos (GM-CSF), Interleucina-6 (IL-6), Apolipoproteína E (APOE) e Prostaglandina E2 sintase (PGE2) foram avaliados por qRT-PCR. Resultados: a radiação ionizante suprime a expressão gênica de transcritos essenciais para a regeneração óssea, bem como a viabilidade celular, como observado nos grupos IrI e IrL. Conclusão:embora isso possa levar à perda da osseointegração e falha do implante, as MSCs apresentaram maior atividade aos 49 dias do que aos 3 e 14 dias (AU)

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Bonding to different dental restorative materials is challenging. This study aimed to evaluate the effect of a 10-MDP-based dentin adhesive on the shear bond strength (SBS) of self-adhesive resin cement (RC) to implant abutment materials. One hundred and twenty specimens were obtained from zirconia (ZO), cobalt-chromium alloy (CoCr), and commercially pure titanium (Ti), which were treated as follows (n = 10): control group-non-treated (CG), 10-MDP-based dentin adhesive (SB), light-cured SB (SB-LC), and zirconia primer (ZP). Blocks of RC were buildup and, after 24 h, were tested for bond strength. Data of SBS (MPa) were submitted to two-way ANOVA and Tukey test (α = 0.05). There was no difference in SBS among materials for CG and ZP, higher SBS were recorded for Ti SB and Ti SB-LC compared to ZO upon the same surface treatments. For the comparisons among treatments, SB-LC showed the highest SBS for CoCr. For ZO and Ti, higher SBS were recorded with SB and SB-LC. No cohesive failures were observed. It was concluded that the surface treatment with 10-MDP-based materials increased the bond strength of the resin cement to abutment materials, which showed to be material dependent.

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The need for new teaching-learning strategies stems from the great change society is going through. The so-called digital natives are part of a generation that lives in a hyperactive rhythm making it increasingly difficult to adapt to traditional classrooms. In Dentistry Courses, new strategies and pedagogical tools have been used, suchas active learning methodologies. In this context, the Discipline of Histology of the Dentistry Course has been proposing the use of some innovative pedagogical strategies. This work will present the experience with team-based learning (TBL), which articulates individual (iRAT) and group activities (gRAT), stimulates the application of concepts and can articulate with other methodologies such as flipped classroom, case study and problematization. This study alsoanalysedstudents' performance in iRAT and gRAT with the application of TBLand discussed the results achieved. Itwas conducted by analysingthe scoresof 240 first-year students of the Histology course in 2016, 2017 and 2018. Student scores, individually and in groups, were statistically analysedby the paired student t-test. Comparisons were made between the iRAT and gRAT activities about gender and the full-time and night classes by the one-way ANOVA and Kruskal-Wallis test. All students obtained higher group scores when compared to individual test results (p <0.001). There was no significant difference between sexes and study period. Group performanceexceeds individual performance. From this, it can be inferred that TBL can be a good strategy to use in dentistry, as an interaction between students leads to higher performance and problem-solving capacity (AU).

A necessidade de novas estratégias de ensino-aprendizagem decorre da grande mudança pela qual a sociedade está passando. Os chamados nativos digitais fazem parte de uma geração que vive em um ritmo hiperativo tornando cada vez mais difícil a adaptação às salas de aula tradicionais. Nos cursos de Odontologia, novas estratégias e ferramentas pedagógicas têm sido utilizadas, como metodologias ativas de aprendizagem. Nesse contexto, a Disciplina de Histologia do Curso de Odontologia tem proposto a utilização de algumas estratégias pedagógicas inovadoras. Este trabalho apresentará a experiência com a aprendizagem baseada em equipe (TBL), que articula atividades individuais (iRAT) e em grupo (gRAT), estimula a aplicação de conceitos e pode se articular com outras metodologias como aula invertida, estudo de caso e problematização. Este estudo também analisou o desempenho dos alunos no iRAT egRAT com a aplicação da TBL e discutiu os resultados alcançados. Foi realizado por meio da análise das notas de 240 alunos do primeiro ano do curso de Histologia em 2016, 2017 e 2018. As notas dos alunos, individualmente e em grupos, foram analisadas estatisticamente por meio do teste t-student pareado. As comparações foram feitas entre as atividades iRAT e gRAT sobre gênero e as aulas em período integral e noturno pelo teste ANOVA one waye teste de Kruskal-Wallis. Todos os alunos obtiveram pontuações mais altas do grupo quando comparados aos resultados dos testes individuais (p <0,001). Não houve diferença significativa entre os sexos e o período de estudo. O desempenho do grupo excede o desempenho individual. A partir disso, pode-se inferirque o TBL pode ser uma boa estratégia para uso em odontologia, pois uma interação entre os alunos leva a um maior desempenho e capacidade de resolução de problemas (AU).

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To perform a systematic review focusing on the prognosis of oral cavity squamous cell carcinoma (OSCC) in young patients (≤40 years old) compared to older (>40 years old). Four databases were used in our search strategy. First, all titles were systematically organized using the Covidence platform online. In the second phase, 118 full texts of potentially eligible studies were analyzed by reviewers independently and in pairs. Twelve studies were considered eligible for data extraction. The relapse was higher in the young than in controls (pooled relative risk (RR) = 1.31; 95% CI [1.10-1.56]). The 5-year disease-free survival (DFS) was worse in young group (pooled hazard ratio (HR) = 0.73; 95% CI [0.63-0.85]) but the 5-year overall survival (OS) estimate was similar between the groups (pooled HR = 0.84; 95% CI [0.70-1.00]). While the 5-year OS was similar between groups, the number of relapses and 5-year DFS were worse in patients with OSCC ≤40 years old.

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BACKGROUND: Nylon is a polymer that its use to reinforce dental resins has shown positive results such as increased flexural strength. The aim of this study was to evaluate the bond strength between dental resins and a nylon reinforcement. MATERIAL AND METHODS: Forty cylindrical nylon blocks with 13 x 23 mm with 0.5% by volume of silica and 40 without were made. Half of the samples of each nylon composition were sandblasted with aluminum oxide (50µm) for 3 s (2.8 bar pressure, distance: 20 mm, incidence angle: 90o). On the nylon blocks, cylinders of chemically activated acrylic resin and indirect composite resin were made, with a bonding area of 6,28 mm2. Eight different groups were obtained according to the material used and the surface treatment (n = 10): Acrylic Resin + Nylon; GAS: Acrylic Resin + Nylon with Silica; GAT: Acrylic Resin + Nylon (Al2O3); GAST: Acrylic Resin + Nylon with Silica (Al2O3); GC: Composite Resin + Nylon; GCS: Composite Resin + Nylon with Silica; GCT: Composite Resin + Nylon (Al2O3); GCST: Composite Resin + Nylon with Silica (Al2O3). The shear test was carried out. The Student's and the Kruskal-Wallis test was adopted. RESULTS: There was no statistically difference in the bond strength for nylon with silica for the acrylic resin group. For the composite groups, nylon with silica did not present a statistically difference without surface treatment (p = 0.10) and with surface treatment the bond strength decreased (p = 0.000). The GCT showed a higher bond strength (0.89 MPa). The surface treatment improved the bond strength for the both groups. CONCLUSIONS: The presence of silica in the nylon composition did not influence the bond strength between materials evaluated. However, the surface treatment with aluminum oxide proved to be favorable for this adhesion. Key words:Nylons - Resins, Synthetic - Structures Strengthening - Dental Research.

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Objetive: The aim of this study was to assess the profile of dental students at the ICT/CSJC-UNESP School of Dentistry and their preferred studying style. Material and methods: Data on age, sex, place of residence, first-choice course, secondary education background and study method preference were collected from an online questionnaire given in the second year dental materials course (first class) of the day and evening courses of the years 2016 to 2019. All data were tabulated and submitted to one-way ANOVA and to t test, both with α= 0.05. Pearson correlation test was performed between demographic data and study method preference (α = 0.05). Results: Most of the students were women living in São José dos Campos city who had chosen Dentistry as their first-choice course. Many were originally from other cities and lived in shared accommodation with friends. The majority stated that private high school was their main educational background. The students' age and place of living showed to correlate with study method preference. Conclusion: Although ICT/CSJC-UNESP students were from millennial and post-millennial generations, students with public secondary education preferred studying alone, while those from private education preferred studying in group (AU).

Objetivo: O objetivo do estudo foi o de assessar o perfil de alunos do curso de Odontologia do ICT/CSJC-UNESP e seu método de estudo de preferência. Material e Métodos: Dados de idade, sexo, local de residência, primeira escolha de curso, formação escolar prévia e método de estudo de preferência foram coletados a partir de um questionário online aplicado no primeiro dia de aula aos alunos do segundo ano na disciplina de materiais odontológicos dos cursos integral e noturno entre 2016 e 2019. Os dados foram tabulados e submetidos a ANOVA um fator e ao teste t, ambos com α = 0,05. O teste de correlação de Pearson foi realizado para os dados demográficos e métodos de estudo de preferência (α= 0,05). Resultados: A maioria dos estudantes eram mulheres que moravam em São José dos Campos, quem tinham a Odontologia como a primeira escolha de curso. Muitos eram originariamente de outras cidades e compartilhavam moradia com amigos. A maioria relatou ter a escola particular como maior parte no ensino fundamental e médio. A idade do aluno e o local de residência mostraram estar correlacionadas ao método de estudo de preferência. Conclusão: Embora os estudantes do ICT/CSJC-UNESP sejam da geração "millennial" e "pós-millennial", aqueles com formação em escola secundária pública preferiram estudar sozinhos, enquanto que aqueles com formação em escola particular preferiram estudar em grupo (AU).

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OBJECTIVES: Evaluate the modulating effect of ionizing radiation, blood cytokine levels, and bone remodeling of the interface around the implant to understand the radiation mechanisms which can impair the implants receptor site. MATERIAL AND METHODS: Sixty rats were submitted to grade V titanium implants in the femurs and were divided into the following groups: no-irradiation (N-Ir): control group with implant only; early-irradiation (E-Ir): implant + irradiation after 24 h; late-irradiation (L-Ir): implant + irradiation after 4 weeks; and previous-irradiation (P-Ir): irradiation + implant after 4 weeks. The animals in the E-Ir, L-Ir, and P-Ir groups were irradiated in two fractional stages of 15 Gy. At 3 days, 2 weeks, and 7 weeks after the final procedure, five animals were randomly euthanized per group. Serum levels of TNF-ɑ, IL-1ß, TGF-ß, IL-6, M-CSF, and IL-10 were measured from blood collected prior to euthanasia using the ELISA test. The pieces containing the implants were subjected to immunohistochemical labeling using the tartrate acid resistant to phosphatase, osteocalcin, and caspase-3 markers and mCT. The ANOVA test was used for statistical analysis, and the Tukey multiple comparison test (p < 0.05) was applied. RESULTS: The results indicated that ionizing radiation modifies the production of pro- and anti-inflammatory serum cytokines, the expression of proteins involved in bone remodeling and cellular apoptosis, as well as changes in bone formation. CONCLUSIONS: The results suggests that a longer period between radiotherapy and implant placement surgery when irradiation occurs prior to implant installation would allow the recovery and renewal of bone cells and avoid future failures in osseointegration. CLINICAL RELEVANCE: The search for modifications caused by ionizing irradiation in bone tissue can indicate the ideal period for implant placement without affecting the osseointegration process.

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