Health changes during Covid-19: a nationwide study with dental students

OBJECTIVE: To assess the changes in stress levels, social behavior, dietary and parafunctional habits, oral hygiene, among other conditions perceived by dental students in Brazil during the Covid-19 pandemic and evaluated the correlations between stress level and other variables. METHODS: An online questionnaire was developed and validated. Undergraduates enrolled in private and public dental schools were recruited by convenience sampling. Data were collected on the perceived changes regarding stress levels, financial and social characteristics, dietary habits, oral hygiene, health conditions, and parafunctional habits. Quantitative variables were expressed as absolute and relative frequencies. Wilcoxon test evaluated comparisons between perceived changes, and correlations between changes in stress levels and other variables were analyzed by Spearman correlation (α = 0.05). RESULTS: A total of 638 dental students, mean age of 22.95 ± 4.10 years, participated in the study. During the pandemic, the reported stress levels increased while household income decreased (p < 0.05). Late dinners and mindless eating increased in frequency, whereas oral hygiene decreased (p < 0.05). Most of the health conditions and parafunctional habits assessed changed (p < 0.05). Perceived stress levels showed poor negative correlations with household income (rS = −0.14), poor positive correlations with the pressure to contribute financially in the household (rS = 0.19), and poor positive correlations with food choice frequency (rS = 0.15) (p < 0.05). CONCLUSIONS: Dental students reported perceived changes in stress levels, dietary habits, oral hygiene, health conditions, parafunctional habits, and social behavior. Moreover, the results showed poor correlations, as students with higher stress levels tended to have the lowest household income, feel pressured to contribute financially in the household, and present a high meal intake frequency

Desensitizing Agent Previously Applied During In-Office Bleaching: A Double-Blind Randomized Clinical Trial

Objective: To compare the clinical effect of two desensitizing agents used before the application of a bleaching gel based on 35% hydrogen peroxide (HP). Material and Methods: 30 patients were selected, and two desensitizing agents with different mechanisms of action were applied: Fluorine Neutral 2% (FN), which acts by blocking dentinal canaliculi while Potassium Nitrate 5% with 2% Sodium Fluoride (PN/SF) that acts in nerve transmission and blockade. Desensitizers were used before the application of 35% HP. For whitening, three clinical sessions were performed, with an interval of seven days, with three applications of the bleaching gel for 15 minutes, totaling 45 minutes/session. Tooth sensitivity (TS) was assessed with the numerical analog scale, and a spectrophotometer was used to obtain the color variation (ΔE).ΔE were submitted to ANOVA and Tukey test (p<0.05), and TS data were submitted to a two-way ANOVA analysis. Results: For sensitivity experience, the Tukey test indicated differences between PN/SF and the placebo I, but there was no statistically significant difference between FN and the placebo II. The TS was lower when the desensitizing gel was used during the bleaching procedure compared to after treatment, regardless of the desensitizing agents. Conclusion: PN/SF before in-office tooth bleaching can reduce TS intensity, and the use of desensitizing gel before bleaching did not affect the bleaching efficacy

Uso do desenho digital na recuperação do sorriso

Um tratamento estético ideal deve simultaneamente promover a melhor forma e função dos dentes e tecidos, enquanto recupera a beleza do sorriso sem comprometer a saúde bucal e a estabilidade dentária. Assim, o objetivo deste trabalho foi apresentar um caso clínico com necessidade estética, o qual o tratamento incluiu a técnica de DDS para planejar a reabilitação dos dentes anteriores com laminados cerâmicos. Desta forma, uma equipe multidisciplinar foi requerida para restaurar defeitos por razões estéticas e/ou funcionais, bem como, o uso dos recursos digitais, que, quando bem aplicados antes dos tratamentos restauradores melhora a comunicação entre o time interdisciplinar, o paciente e o técnico de prótese. Desse modo, conclui-se que o DDS é um instrumento importante para o desenvolvimento efetivo do tratamento odontológico e, quando combinada com outras ferramentas, proporcionam um tratamento personalizado, respeitando os desejos e características de cada paciente proporcionando um aspecto psicológico positiva na vida do pacienteThe optimal aesthetic treatment should promote the best shape and function of teeth and tissues while restoring smile beauty without compromising oral health and dental stability. Thus, the objective of this study was to present a case with aesthetic necessity, and the treatment included DSD technique to plan the rehabilitation of anterior teeth with ceramic veneers. Hence, a multidisciplinary team was asked to restore problems for aesthetic and / or functional reasons, as well as the use of digital resources, which, well before restorative testing, improves communication between interdisciplinary time, the patient and the technician of prosthesis. Therefore, it concludes that DSD is an important tool for the effective development of dental treatment and, when combined with other tools, provides personalized treatment, respects the wishes and characteristics of each patient with a positive psychological aspect in the patient\u27s lif

Effects of primer amount on marginal adaptation, nano leakage and bond strength of adhesive systems after thermomechanical aging

Orientador: Luis Alexandre Maffei Sartini PaulilloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O estudo teve como objetivo avaliar a influência da quantidade de primer usada na hibridização do substrato na resistência de união por microtração, nanoinfiltração e adaptação marginal em restaurações com sistemas adesivos e resina composta após envelhecimento termomecânico. Foram selecionados 48 molares hígidos que foram restaurados em uma cavidade tipo classe I pela técnica incremental com sistema adesivo convencional de três passos (Adper Scotchbond Multiuso - 3M ESPE) e sistema autocondicionante de dois passos (Clearfill SE bond - Kuraray). Para o sistema adesivo convencional foi realizado o condicionamento ácido total e para o sistema adesivo autocondicionante, o condicionamento ácido foi seletivo no ângulo cavosuperficial em esmalte. Em seguida, os dentes foram alocados aleatoriamente em 6 grupos resultantes da interação da aplicação de uma quantidade padronizada de 1, 2 ou 3 gotas de primer e sistema adesivo. Todos os dentes foram restaurados com a resina composta microhíbrida Charisma (Heraeus Kulzer). Após o polimento das restaurações, estas foram moldadas com polivinilsiloxano e as réplicas foram obtidas em resina epóxica. Em seguida, os espécimes foram levados à máquina de ciclagem termomecânica ERIOS 37000 (ERIOS, São Paulo, Brasil), na qual realizou-se o envelhecimento artificial da restauração através de 200.000 ciclos com carga de 86 N a uma frequência de 2 Hz associados a ciclos térmicos com a temperatura variando entre 5ºC, 37ºC e 55ºC, a cada 30 segundos. Terminado o envelhecimento, obteve-se novas réplicas que foram levadas ao microscópio eletrônico de varredura (MEV) para análise de fendas em comparação com as imagens iniciais. Em seguida os dentes foram submetidos ao ensaio mecânico de resistência de união à microtração por meio de palitos obtidos da interface vestibular, e, posteriormente, avaliou-se o padrão de fratura usando MEV. Para análise de nanoinfiltração, oito palitos de cada grupo foram separados, aleatoriamente, para se avaliar a infiltração de íons de nitrato de prata em MEV. Após o teste termomecânico, os dados foram submetidos à Análise de Variância dois fatores e teste de Tukey com ?= 0,05. Quando o excesso de primer na camada adesiva foi avaliado, o sistema adesivo convencional de três passos apresentou melhores resultados de resistência à união quando comparado ao sistema adesivo autocondicionante de dois passos (?= 0,0015). A quantidade de gotas influenciou a resistência de união à microtração (?= 0,0057). A nanoinfiltração foi maior quando se utilizou maior quantidade de primer e o envelhecimento termomecânico aumentou a formação de fendas marginais. O uso de primer em excesso não é recomendado pois reduz a resistência de união à microtração e forma uma camada híbrida de baixa qualidadeAbstract: This study aimed to evaluate the effects of the amount of primer used in the tooth substrate hybridization on the microtensile bond strength (?TBs), nanoleakage and marginal sealing in dental restorations with adhesive systems and composite resin after thermomechanical aging. A total of 48 human molars were restored class I cavities with incremental technique with a three-step etchand- rinse adhesive system (Adper Scotchbond Multipurpose, 3M ESPE) and twostep self-etching adhesive system (Clearfill SE Bond, Kuraray), For three-step etch-and-rinse adhesive system used total acid etching and for the two-step selfetching system adhesive only enamel cavosurface was acid etching. Then, the teeth were aleatory alocated in 6 groups resulted the interaction between the factors application of standard quantity of primer (1, 2 or 3 drops) and adhesive systems. Afterward a standardized amount of each primer was applied (1, 2, or 3 drops of primer). All teeth were restored with microhybrid composite resin (Charisma, Heraeus Kulzer). After polishing of restorations, they were molded with polyvinylsiloxane and replicas were obtained with epoxy resin. Then the specimens were taken to thermomechanical cycling machine (model 37000 ERIOS), which carried out the artificial aging of restoration through 200,000 cycles with 86 N load at a frequency of 2 Hz associated with thermal cycling and temperature ranging from 5, 37and 55°C every 30 seconds. After aging, new replicas were obtained and images were taken by scanning electron microscope (SEM) to analyze gaps. These images were compared to the initial ones. Then the teeth were subjected to ?TBs testing through beams obtained from buccal interface, and fracture pattern was evaluated using SEM. For nanoleakage analysis, eight beams of each group were randomly separated to assess infiltration with silver nitrate ions and subsequently evaluated by SEM. After the mechanical test, the data were subjected to statistical analysis using two-way Analysis of Variance and Tukey's test (? = 0.05). When primer excess was evaluated at the adhesive layer, the three-step etch-and-rinse adhesive system showed higher bond strength results x when compared to two-step self-etching adhesive system (? = 0.0015). The primer excess influenced ?TBS (? = 0.0057). Nanoleakage was higher when using larger amount of primer was used. Thermomechanical aging increased the formation of marginal gaps. The use of primer in excess is not recommended, because the excess reduces the ?TBs and creates an unsatisfactory hybrid layer on tooth substrateMestradoDentísticaMestra em Clínica Odontológic

Effect of cleaning protocol on silica deposition and silica-mediated bonding to Y-TZP

To evaluate the effect of cleaning methods on the deposition of silica on yttria-stabilized zirconium dioxide (Y-TZP) surface and on the silane-silica mediated bond strength between Y-TZP and resin cement. Y-TZP slabs were air-abraded with 30 μm silica-coated alumina particles and distributed in three groups: no cleaning, cleaning with a stream of oil-free air/water spray for 5 s and cleaning with an ultrasonic bath in water for 10 min. The distribution of Si on the Y-TZP surfaces was recorded using energy dispersive spectroscopy (EDS). After the treatment was applied, Y-TZP slabs (n = 20) received a primer application and resin cement cylinders were built on the surface. After storage (24 h) in water storage or 3 months plus thermocycling; n = 10), microshear bond strength test (μSBS) was performed. X- ray Photoelectron Spectroscopy (XPS) characterized the chemical bonds between the silica layer and the silane-containing primer. Data were analyzed using ANOVA and Tukey test, as well as Weibull analysis (α = 0.05). Cleaning method had a significant effect on the amount of Si deposited on zirconia surface (p < 0.001) and, consequently, on bond strength (p < 0.001). Storage/aging also had a significant effect on bond strength (p < 0.001). Low values of Weibull moduli for bond strength were observed for all groups after aging. XPS showed silane-silica chemical interaction for all groups. The silica deposited by tribochemical coating to Y-TZP was removed by the cleaning methods evaluated, compromising bond strength. Stability of the bonding is also a concern when no cleaning method is applied351116031613The authors would like to gratefully thank Brazilian Center for Research in Energy and Materials (CNPEM) for X-ray Photoelectron Spectroscopy suppor

Influence of whitening dentifrices and mechanical brushing on color change and surface roughness of bulk fill resins

of whitening dentifrices during oral hygiene may cause surface modifications such as color change (&#916;E) and increase surface roughness (Ra) of composite resin. Aim: This study aimed to evaluate the effect of whitening dentifrices and mechanical brushing on color change and surface roughness of Bulk Fill (Filtek Bulk Fill - F) and (Aura Bulk Fill - A) composite resins. Materials and methods: Sixty cylindrical specimens were fabricated of each composite resin. After initial color evaluations (Konica Minolta CM-700d), with D65 standard illuminant, and the surface roughness (Surfcorder SE 1700, Kosalab), the specimens were assigned (n=10) according to the whitening dentifrice used: True White (T), Colgate Total 12 Professional Whitening (D), Luminous White Advanced (L). Specimens were submitted to mechanical brushing (10,000 cycles); new color and surface roughness evaluations were taken. Data were analyzed by ANOVA, Duncan test and Dunnet test were used to identify differences between groups (&#945;=5%). Results: The results showed that the tooth brushing time promoted a significant increase in &#916;E of the FT group. The FD group exhibited intermediate values of &#916;E and was similar to all groups tested. There was a significant increase in the surface roughness of the AD and AT groups after the mechanical tooth brushing. Conclusion: The results showed no significant changes were observed in surface roughness for F groups after toothbrushing. It be concluded that the color change and surface roughness of the composite resins after toothbrushing are dependent on the interaction between the composition of the composite resin and the characteristics of the dentifrice