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Collares FM, Ogliari FA, Lima GS, Fontanella VRC, PivaE, Samuel SMW. Ytterbium trifluoride as a radiopaque agentfor dental cements. International Endodontic Journal, 43, 792–797, 2010. Aim To evaluate the radiopacity, degree of conversion(DC) and flexural strength of an experimental dentalcement, with several added radiopaque substances.Methodology Titanium dioxide, quartz, zirconia,bismuth oxide, barium sulphate and ytterbium triflu-oride were added to the experimental cement in fivedifferent concentrations. Radiopacity was evaluatedwith a phosphor plate system, and the radiodensity ofspecimens was compared with an aluminium step-wedge. DC was evaluated with FT-infrared spectroscopyfollowing 20 s of photo-activation. Specimens withdimensions of 12 · 2 · 2 mm were used for theflexural strength test. Data were analysed with two-way anova and Tukey’s post hoc test.Results Radiopacity of the experimental dentalcements with barium sulphate and bismuth oxide at40% and ytterbium fluoride at 30% and 40% showedno significant differences in comparison with 3 mm ofAl (181, 96).Conclusions The experimental dental cements withat least 30% added ytterbium trifluoride had satisfac-tory radiopacity without influencing other properties.Keywords: barium sulphate, bismuth oxide, dentalcement, radiopacity, root canal sealants, ytterbiumtrifluoride.

The aim of this study was to evaluate the influence of different curing conditions on degree of conversion, glass transition temperature (Tg), microhardness and impact strength of an autopolymerizing acrylic resin. Twenty-one acrylic resin baseplates with wire clasps simulating removable appliances were produced according to three curing conditions and allocated in three groups (n = 7): Group A—curing in air during 1 h at room temperature and pressure; Group M—treated as in Group A plus additional heating by microwave energy (500 W; 3 min); Group TP—curing in water at 50 8C, during 15 min under 20 psi pressure. Microhardness was measured using a Knoop microhardness indenter, and the degree of conversion and Tg were determined by differential scanning calorimetry (DSC). For impact strength test, 12 non-notched specimens were fabricated per group according to ASTM D256 standard. Data were analyzed statistically by one-way ANOVA and Tukey’s test (p 0.05). No significant differences were found among the Tg values of the three groups (p > 0.05). A better performance may be expected when autopolymerizing acrylic resins are cured under controlled heat and pressure conditions.

O uso de dentes humanos para o ensino e pesquisa em Odontologia é uma prática freqüente. A implantação de Bancos de Dentes Humanos (BDH) em instituições de ensino é fundamental para viabilizar a manipulação segura para aprendizagem, pesquisa e inovações tecnológicas que façam uso de dentes humanos. Para que seu funcionamento seja adequado, a organização e a legalização do uso de dentes devem ser divulgados. Procedimentos relativos às etapas de arrecadação, limpeza e desinfecção, separação e armazenamento, cessão e/ou empréstimo e de biossegurança devem ser desenvolvidos, aprimorados e colocados ao alcance dos interessados. Este artigo tem como objetivo revisar a literatura acerca da importância do BDH em instituições de ensino e pesquisa assim como seus aspectos práticos, legais, técnicos e científicos., The use of human teeth for teaching/education and research in dentistry is a common practice. The establishment of Human Teeth Bank (BDH) in institutions of education is essential to enable the safe handling in teaching, research and the discovery of new technologies which make use of human teeth. Before BDH establishment is appropriate, its organization and legalization must be disclosed. Procedures of collection, cleaning and disinfection, separation and storage, disposal and/or loan and biosecurity should be developed and improved. The aim of this study is to search the number of BDH inside schools of Dentistry units at Rio Grande do Sul state and to review the literature about the importance of BDH in institutions of education and research as well as its legal, technical and scientific aspects.

This study tested the null hypothesis that the number of applications of a self-etching primer would not infl uence the microtensile bond strength at the interface resin/enamel. Bovine teeth were fl atted to expose the prismatic enamel with wet 600 grit silicon carbide papers. The teeth were divided into two groups: FB 1coat, FuturaBond (Voco) applied according to the manufacturer’s instruction for 30 s; and, FB 4coats, applied four times, 30s each. Then, they were restored with Polofi l (Voco) resin composite. After 24h, samples were cut with a diamond low speed saw under water cooling to obtain stick-shaped specimens of approximately 0,5 mm2 cross-sectional area. The sticks underwent microtensile testing at a speed of 1 mm/min. The bond strength, in MPa, was: FB 1coat, 33.57 ±8.77 (18); FB 4coats: 33.57 ±8.77 (18). This values, at t student test, had not showed signifi cant difference (p=0.58). In this study, the number of coats did not interfere at the values of bond strength at the interface resin/enamel., Este estudo testou a hipótese nula de que o número de camadas de aplicação de um primer auto-condicionante pode não influenciar não resistência da interface adesiva resina/esmalte à microtração. Dentes bovinos foram niveladas, para expor os prismas de esmalte, utilizando-se lixa d´água #600. Os dentes foram divididos em dois grupos: FB 1 camada, FuturaBond (Voco) aplicado de acordo com as recomendações do fabricante por 30 s; e, FB 4 camadas, aplicadas quatro vezes, 30s cada. Foram então restaurados com a resina composta fotopolimerizável Polofil (Voco). Após 24 horas as amostras foram cortadas com um disco diamantado em baixa rotação sob abundante irrigação para obter palitos de aproximadamente 0,5 mm2 de área. Os palitos foram submetidos á microtração a uma velocidade de 1 mm/min. A resistência adesiva, em MPa, foi: FB 1 camada, 33.57 ±8.77 (18); FB 4 camadas: 33.57 ±8.77 (18). Esses valores, no teste t de student, não apresentaram diferença significativa (p=0.58). Nesse estudo, o número de camadas não interferiu nos valores de resistência de união da interface resina/esmalte.

White spot lesions are still a concern for orthodontic patients. The objective of this study was to assess the remineralizing and antibacterial effect of a newly developed orthodontic adhesive. The compounds 1,3,5-tryacryloylhexahydro-1,3,5-triazine (TAT) and phosphate invert glass containing 10 mol% of niobium pentoxide (PIG-Nb) were added at 20 and 5 wt%, respectively, to an experimental adhesive (75 wt% BisGMA, 25 wt% TEGDMA, 5 wt% fummed silica, and photo-initiator system), called TPN. A group without the addition of these compounds was used as Control and the orthodontic adhesive Transbond XT (TXT) was used for comparison. Antibacterial activity was evaluated through surface biofilm formation, mineral deposition, and degree of conversion (DC) through Raman microscopy, Knoop hardness after softening in solvent, and bracket dislodgement (BD). TPN group presented a reduction in bacterial growth when compared to Control and TXT. Mineral deposits were observed on the surface of TPN adhesive after 14 and 28 days of immersion in artificial saliva. There was an increase in DC after 28 days, whereas TPN group presented the highest DC. All groups underwent some degree of softening. No significant changes were observed in BD after 28 days of immersion in artificial saliva. The newly developed orthodontic adhesive, with addition of 20 wt% TAT and 5w% PIG-Nb, exhibited antibacterial activity and was capable to induce mineral deposition on its surface in vitro. The orthodontic adhesive developed in this study with antibacterial activity and mineral deposition could be a reliable choice for brackets adhesion.

Aim: To evaluate the long-term post push-out bond strength to dentin, water sorption, solubility and swelling of conventional and self-adhesive dual-cure resin cements. Methods: Forty-eight bovine roots were prepared for fiber post cementation with RelyX ARC and RelyX U100. According to resin cement and storage time (24 h and 6 months), 4 groups were assessed using the push-out test. Water sorption and solubility were performed according to ISO 4049:2009. The swelling coefficient was obtained using cement disks of each material immersed in distilled water until the swelling equilibrium was reached. The mass of dry and swelled polymer and solvent density were used to calculate the coefficient. Statistical data analysis was performed using Student's t-test for water sorption, solubility and swelling coefficient and the Kruskal-Wallis and Dunn multiple comparison tests for push-out analysis with a significance level of 0.05. Results: The immediate bond strength was not significantly different between RelyX ARC (3.09 MPa) and RelyX U100 (3.78 MPa) (p>0.05). RelyX U100 showed higher (p0.05) between groups. The swelling coefficient of the RelyX U100 group was significantly higher than that of the RelyX ARC group (p

Objetivo Avaliar a eficácia dos métodos de desinfecção em microondas e imersão em ácido peracético em resina acrílica termopolimerizável, autopolimerizável e resina acrílica polimerizada por microondas, contaminadas com Candida albicans. Métodos Cinco amostras foram preparadas para cada tipo de resina acrílica. Todas foram infectadas com Candida Albicans, incubadas a 37 ° C durante 24 h. O grupo submetido a energia de microondas foi irradiada com uma potência de 840W durante 1 minuto e o outro grupo foi submetido a desinfecção por imersão de ácido peracético a 0,2% durante 5 minutos. Resultados Todas as amostras mostraram estar contaminadas depois do período de incubação. Depois dos diferentes processos de desinfecção, tanto a imersão em 0,2% de ácido peracético, como a irradiação de microondas foram eficazes na desinfecção dos 3 tipos de resinas acrílicas contaminados por Candida Albicans. Conclusão Concluiu-se que a imersão em ácido peracético 0,2% durante 5 minutos e a irradiação de microondas com potência de 840W durante 1 minuto são métodos eficazes para a desinfecção de resina acrílica termopolimerizável, resina acrílica autopolimerizável e resina acrílica polimerizada por microondas, contaminados com Candida Albicans. Objective The objective of this study was to evaluate the effectiveness of disinfection methods in microwave and immersion in peracetic acid in heatcured, self-cured and microwave-cured acrylic resin, contaminated with Candida albicans. Methods Five specimens were prepared for each type of acrylic resin. All were infected with Candida Albicans, incubated at 37°C for 24 hours. The group which underwent microwave energy was irradiated with a power of 840W for 1 minute and the other group underwent disinfection by soaking of 0.2% peracetic acid for 5 minutes. Results All samples proved to be contaminated after the incubation period. After the different processes of disinfection, both immersion in 0.2% peracetic acid as microwave irradiation were effective in disinfection of the 3 types of acrylic resins contaminated by Candida Albicans. Conclusion Concluded that soaking in 0,2% peracetic acid for 5 minutes with microwave irradiation power 840W for 1 minute are effective methods for disinfecting heat-cured acrylic resin, self-cured acrylic resin and microwave-cured acrylic resin, contaminated with Candida Albicans.

Objective The study aimed to evaluate the influence of virtual learning object (VLO) in the theoretical knowledge and skill practice of undergraduate dentistry students as it relates to zinc phosphate cement (ZPC). Methods Only students enrolled in the dentistry course the course were included in the trial. Forty-six students received a live class regarding ZPC and were randomized by electronic sorting into the following 4 groups: VLO Immediate (GIVLO n = 9), VLO longitudinal (GLVLO n = 15) and two control groups without VLO (GIC n = 9 and GLC n = 13). The immediate groups had access to VLO or a book for 20 min before the ability assessment, whereas the longitudinal groups had access to VLO or a book for 15 days. Results A pre- and posttest on theoretical knowledge and two laboratory skill tests, evaluated by blinded examiners, were performed regarding zinc phosphate cement manipulation in all groups. The students who used the VLO obtained better results in all the tests performed than the control students. The theoretical posttest showed a significant difference between the longitudinal groups, GLC (6.0 ± 1.15) and GLVLO (7.33 ± 1.43). The lower film thickness presented with a significant difference in the VLO groups: (GIC 25 ± 9.3) and GIVLO (16.24 ± 5.17); GLC (50 ± 27.08) and GLVLO (22.5 ± 9.65). The higher setting time occurred in the VLO groups, and the immediate group showed a significant difference (GIC 896 ± 218.90) and GIVLO (1138.5 ± 177.95). Conclusions The ZPC manipulated by the students who used the VLO had better mechanical properties in the laboratory tests. Therefore, the groups that used the VLO had clinical handling skills superior to its controls and greater retention of knowledge after 15 days.

The purpose of this study was to assess the antimicrobial efficacy of a peracetic acid-based disinfectant for decontamination of heat-polymerized, chemically activated and microwave-polymerized acrylic resins. Resin plates were contaminated in vivo upon intraoral use by 10 volunteers for 7 nights and slabs were contaminated in vitro by contact with Bacillus subtilis and Bacillus stearothermophilus. The contaminated acrylic resin specimens were immersed in a 0.2% peracetic acid-based disinfectant (Sterilife®; Lifemed) for 5 min or 10 min and placed in a BHI culture medium. After incubation at 37°C for 48 h, bacterial growth was assessed by analyzing turbidity of the medium. For all types of acrylic resin, no turbidity of the medium was observed for any of the resin specimens immersed in the peracetic acid-based disinfectant for either 5 or 10 min. On the other hand, the media with specimens that were not immersed in the disinfectant (control) showed turbidity in 100% of the cases, indicating the presence of microorganisms in both tested conditions. In conclusion, immersion for at least 5 min in a 0.2% peracetic acid-based disinfectant promoted high-level disinfection of heat-polymerized, chemically activated and microwave-polymerized acrylic resins contaminated with either human saliva or Bacillus subtilis or Bacillus stearothermophilus. O objetivo deste trabalho foi avaliar a eficácia antimicrobiológica de um desinfetante à base de ácido peracético na descontaminação de resinas acrílicas termicamente ativada, quimicamente ativada e polimerizada em forno de microondas. Placas de resina foram contaminadas in vivo por meio do uso intraoral por 10 voluntários durante 7 noites e corpos-de-prova de resina foram contaminados in vitro por meio do contato com microrganismos conhecidos: Bacillus subtilis e Bacillus stearothermophilus. Os espécimes contaminados foram imersos em desinfetante à base de ácido peracético a 0,2% (Sterilife®; Lifemed) durante 5 ou 10 min e então colocados no meio de cultura BHI. Após incubação a 37°C for 48 h, o crescimento bacteriano foi avaliado por meio análise da turvação do meio de cultura. Todos os espécimes imersos em ácido peracético por 5 ou 10 min não apresentaram turvação do meio de cultura, enquanto os espécimes contaminados e colocados diretamente no meio de cultura (grupo controle) apresentaram turvação. Concluiu-se que a imersão em ácido peracético por pelo menos 5 min foi eficaz na desinfecção de resinas acrílicas termicamente ativada, quimicamente ativada e polimerizada em forno de microondas contaminadas tanto com saliva humana quanto com Bacillus subtilis ou Bacillus stearothermophilus.

O objetivo foi avaliar as propriedades de um cimento resinoso experimental contendo hidroxietil acrilamida. Foram formulados quatro grupos de cimentos resinosos fotopolimerizáveis: GHEMA0 e GHEMA1 (70 wt% BisGMA/30 wt% HEMA) e GHEAA0 e GHEAA1 (70 wt% BisGMA/30 wt% HEAA). Como sistema iniciador/ativador foi adicionado aos grupos GHEMA0 e GHEAA0 1% mol de CQ e nos grupos GHEMA1 e GHEAA1 (1% mol de CQ e 1% mol de EDAB). A todos os grupos foi acrescentada uma carga de 40% em peso de fluoreto de itérbio. Os cimentos foram avaliados quanto a radiopacidade (n6), colorimetria 24h após imersão em água e óleo mineral (n5), resistência coesiva (n12) e microcisalhamento (n12). Os dados foram analisados por ANOVA de uma via e Tukey com um nível de significância de 5%. Na radiopacidade o GHEAA1 e GHEAAO não apresentaram diferença a 1mm de alumínio. Na colorimetria, o GHEAA1 imerso em água obteve o maior valor de “L” (p0,05), com exceção do GHEMA1 em óleo. Para os valores de “a” o GHEMA1 em óleo foi estatisticamente maior (p

O objetivo do estudo foi investigar a influência da adição de nanotubos de nitreto de boro (BNNTs) nas propriedades de um infiltrante resinoso. Infiltrantes foram formulados a partir de 90% de TEGDMA, 10% de Bis-GMA, em massa e 1% CQ e EDAB, em mol. BNNTs foram adicionados aos infiltrantes nas concentrações de 0,1% e 0,2% em massa, além de um grupo controle contendo somente o infiltrante base. Os infiltrantes preparados foram avaliados quanto ao grau de conversão (GC) (n3) e aplicados em esmalte desmineralizado de dentes bovinos para avaliação do ângulo de contato (CA), energia livre de superfície (SFE) (n5), deposição mineral após 24h, 7d, 14d e 28d (n1), MEV e rugosidade superficial (n6). Os dados de GC, SFE e rugosidade superficial foram analisados estatisticamente por ANOVA de uma via e teste de Tukey (a

O objetivo desse estudo foi avaliar a influência da adição de pontos quânticos de óxido de titânio (TiO2QDs) estabilizados por líquido iônico (BMI.BF4) em adesivo experimental. A carga foi sintetizada com TiCl4 e tetrafluoroborato de 1-n-butil-3-metilimidazólio. O adesivo foi formulado com 66,6% de Bis-GMA, 33,3% de HEMA e sistema fotoiniciador. A carga foi incorporada em 0% (controle, G0) 2,5% (G2,5) e 5% (G5) em massa. A carga foi analisada por microscopia eletrônica de transmissão (MET) a 120 kV. Os adesivos foram avaliados por resistência de união à microtração (n20), amolecimento em solvente (n3), cinética de polimerização (n3) por espectroscopia no infravermelho por Transformada de Fourier e distribuição das partículas por MET 120 kV em G5 polimerizado. Foi realizada análise descritiva do tamanho de partícula, teste t pareado entre dureza inicial e final e ANOVA de uma via e Tukey para os outros testes. As partículas apresentaram 3,54 (±1,08) nm. Não houve diferença estatística (p>0,05) na resistência de união e dureza inicial. G5 apresentou maior amolecimento em solvente (p0,05). G0 atingiu maior taxa máxima de polimerização e maior grau de conversão (60,95 ± 0,40) comparado a G2,5 (59,67 ± 0,13) e G5 (59,50 ± 0,33) (p

O objetivo foi avaliar a influência de duas concentrações de ácido fluorídrico em cerâmicas para CAD/CAM. Amostras (n6) de IPS Empress CAD, IPS e.max CAD e Vita Suprinity, medindo 7 mm x 4 mm x 1,2 mm foram divididas nos grupos controle, condicionada com ácido fluorídrico 5% e 10%. Superfície foi analisada por MEV, rugosidade e ângulo de contato. Para microcisalhamento, usou- se adesivo universal (Scotchbond Universal) e cimento resinoso dual (Relyx Ultimate). Análise estatística realizada por ANOVA de duas vias. Para o ângulo de contato do e.max, obteve-se médias de 71,12 (5%) e 72,11 (10%). Suprinity, 50,38 (5%), 33,05 (10%). Ambas sem diferença estatística entre 5% e 10%. Empress 69,97 (5%) e 84,38 (10%), e somente condicionamento a 10% com p

Objective to determine the physicochemical properties of experimental adhesive resins containing hydroxyethyl acrylamide. Methods Three groups of experimental resin were formulated, G HEAA33% (33.3 wt% HEAA + 66.6 wt% BisGMA), G HEAA50% (50 wt% HEAA + 50 wt% BisGMA), and G HEAA-FREE (33.3 wt% HEMA + 66.6 wt% of BisGMA). The polymerization process of each adhesive resin group, as well as for the homopolymers, BisGMA, HEMA, HEAA, HEMA* without EDAB, and HEAA* without EDAB, was characterized through differential scanning calorimetry (DSC). Elution of monomers was evaluated by 1 H NMR. Dynamic mechanical analysis (DMA) was used to collect the glass transition temperature ( T g ), the storage modulus ( E ′) and the reticulation degree ( ρ ). Flexural strength was calculated by three-point bending test with 0.75 mm/min. Softening in solvent was calculated through hardness before and after immersion in water or ethanol. Results G HEAA50% , G HEAA33% , G HEAA-FREE presented higher polymerization rate ( R p max = 13.52 , 12.3 and 5.3 mmol g −1 s −1 , respectively) than homopolymers HEMA, HEMA* and HEAA*. Group with HEAA presented higher degree of conversion (G HEAA50% = 64.07% > G HEAA33% = 55.82% > G HEAA-FREE = 49.02%; p = 0.008) All groups presented low elution of monomers ( p > 0.05). The values of E ′ were higher on G HEAA33% than G HEAA-FREE ( p = 0.034). T g and flexural strength values of G HEAA-FREE were higher than acrylamide groups ( p = 0.022 and p ρ values. Significance The addition of HEAA increased the materials reactivity and, consequently, improved the maximum rate of polymerization, degree of conversion and the storage modulus of experimental adhesive resin.

Objetivo: O presente estudo tem por objetivo avaliar a influencia da adicao de diferentes concentracoes de subnitrato de bismuto (SN) nas propriedades de materiais para base protetica. Metodos: Foi adicionada 0%, 1%, 2%, 5%, 10% e 20% de SN em peso em resina acrilica autopolimerizavel da marca Classico e submetidos aos ensaios de resistencia a flexao, microdureza Knoop, radiopacidade, analise antimicrobiana, rugosidade e caracterizacao em micro-Raman. O teste estatistico escolhido foi ANOVA de uma via e o teste de comparacoes multiplas de Tukey. O nivel de significância foi de 5% para todos os testes. Resultados: Os resultados de resistencia a flexao obtiveram valores acima do recomendado pela ISO 1567; quanto maior a concentracao da carga maior o valor de microdureza Knoop, sendo estatisticamente significante em 10 e 20%, p

The aim of this systematic review was to evaluate the influence of several methodological variables on the push-out resistance to dislodgment of root filling materials by a meta-regression analysis of the literature. A systematic review was performed by searching the PubMed database using the terms 'push-out' and 'pushout'. Laboratory studies published before March 2015 were included. Two reviewers extracted data regarding country of origin, year of publication, tooth type, smear layer removal, root canal sealer, core material, obturation technique, sample storage, tooth portion, test machine load velocity and slice thickness. Pooled mean resistance to dislodgement of all groups from the included studies was used in a linear meta-regression of random effects (α = 0.05). Of the 850 identified studies, 53 met the inclusion criteria. A meta-regression of the 341 groups extracted from these articles was performed to analyse the influence of each variable on resistance to dislodgement (in MPa). The sealer, core material, obturation technique, slice thickness, storage time, load velocity and tooth portion significantly influence the results (P 0.05). Irrigant solution and smear layer removal did not influence the resistance to dislodgement of the root filling materials (P 0.05). Methodological variables such as sealer, core material, root filling technique, tooth type, tooth portion, slice thickness, storage time and load velocity influenced the resistance to dislodgment. The inclusion and standardization of all related variables could lead to a more comparable and reproducible analysis of the resistance to dislodgment of the root canal sealers.

To evaluate elementary schoolteachers' knowledge and decision making regarding dental trauma in Porto Alegre, Brazil.A questionnaire-based survey was conducted among elementary schoolteachers (n=442). Questions encompassed sociodemographic characteristics and decision making regarding dental trauma. Data on the appropriate answer regarding what to do with a traumatised or avulsed tooth were analysed with multiple logistic regressions, adjusting for age, gender, work experience and previous training.The study population consisted largely of women (90%), was 40 to 49 years old (44.3%) and had more than 15 years of work experience (56.6%). Women (OR=2.68/p=0.041), teachers under 30 years old (OR=4.95/p=0.041), those with more than 15 years of work experience (OR=8.95/p0.001) or those who had already received previous dental trauma instructions (OR=1.95/ p=0.119) were more likely to choose the appropriate answer for an avulsion situation. Teachers under 30 years old (OR=2.88/ p=0.279), those with more than 15 years of work experience (OR=4.55/p=0.001) or those who had received previous training (OR=3.39/p=0.009) presented higher probabilites of choosing the appropriate answer for a crown fracture event.Greater work experience or previous instructions on how to approach dental trauma in the school environment were found to be major factors in schoolteachers' decision making regarding dental trauma.

AIM: The aim of this study was to evaluate the influence of acrylic resin immersion in different mouthwashes on hardness, roughness and color. METHODS: Specimens of an orthodontic self-cured acrylic resin (Orto Clas(r)) were produced and immersed in five mouthwashes: Plax(r) Classic (Colgate(r)); Plax(r) alcohol-free (Colgate(r)); Listerine(r) (Johnson & Johnson(r)); Periogard(r) (Colgate(r)) and Periogard(r) alcohol-free (Colgate(r)). Nine different immersion times were studied: 1, 2, 4, 6, 8, 10, 12, 24 h and 7 days, totalizing 45 groups. The specimens were evaluated before and after immersion by Knoop microhardness (n=5), roughness in Ra parameter (n=5), and colorimetric analysis, CIElab (n=3). RESULTS: All mouthwashes softened the acrylic resins after 7 days of immersion. PlaxÒ alcohol-free showed no statistically significant difference of softening between the immersion times. Listerine(r) showed softening after immersion at all times. Plax(r) alcohol-free and Listerine(r) showed significantly increased values of roughness after 12 h of immersion (p

O objetivo deste trabalho foi avaliar o efeito da substituição do eugenol pelo isoeugenol na formulação do cimento de óxido de zinco e eugenol, em relação às propriedades de tempo de presa e espessura de película, devido à comprovada genotoxicidade apresentada pelo eugenol. Utilizou-se o pó do cimento de óxido de zinco e eugenol (Endofill - Dentsply Herpo) e o isoeugenol (98%). Com base na especificação número 57 da Associação Dentária Americana (A.D.A.) foram avaliados o tempo de presa e a espessura de película. Para determinação do tempo de presa, foram confeccionados corpos de prova de diâmetro interno de 100 mm e espessura de 2 mm, que foram levados à estufa a 37°C. Com o auxílio de uma agulha de Gillmore com 100 g e diâmetro de 2 mm, foi determinado o tempo de presa do material. Foram determinados os seguintes tempos de presa: A - 1h e 08min; B - 1h e 10min; C - 1h e 13min. Para determinação da espessura de película, utilizou-se a proporção de 330 mg de óxido de zinco e 110 mg de isoeugenol colocada entre duas placas de vidro que tiveram a sua espessura medida por um micrômetro. O material espatulado foi colocado sobre uma das placas e coberto com a outra. Sobre as placas foi aplicada uma carga de 147 N por 10 minutos. Após este período, as placas com o cimento interposto foram retiradas e novamente foi medida a sua espessura. A diferença entre a primeira e a segunda medida resultou na espessura de película: A - 30 m; B - 26 m; C - 28 m. Com base nos resultados concluiu-se que, quanto à espessura de película, o material foi aprovado pela especificação que exige a espessura máxima de 50 um. Já quanto ao tempo de presa, este foi além dos 10% em relação ao proposto pelo fabricante, no entanto, como nas obturações de canal este tempo não é crítico, seria viável sugerir a substituição proposta considerando as propriedades analisadas., The aim of this study was to evaluate the effect of the substitution of eugenol by isoeugenol in the formula of the zinc oxideeugenol endodontic sealer, in relation to the properties of setting time and film thickness, due to the known genotoxicity of the eugenol. it was used the powder of zinc oxide-eugenol sealer (Endofill - Dentsply Herpo) and the isoeugenol (98%). Based on the specification No. 57 of the American Dental Association (ADA) the setting time and film thickness were evaluated. To determine the setting time a mold with an internal diameter of 10 mm and thickness of 2 mm were prepared and taken to the stove at 37°C. Using a Gillmore needle weightening 100 g and diameter of 2 mm, the setting time of the material was determined. Three assessments were made at different periods: A -1h e 08 min; B - 1h e 10 min; C - Lhe 13 min. To determine the film thickness, it was used a proportion of 330 mg of zinc oxide and 110 mg of isoeugenol, that was placed between two glass plates that have hat its thickness measured by a micrometer. The spatuled material was placed over one of the plates and covered by the other. A load 147 N was imputed for 10 minutes. After this time, the plates with the interposed sealer were taken off and the thickness was measured again. The diference between the first and second measure resulted on the following film thickness: A - 30 m; B - 26 m; C - 28 m. Based on the resulis, it was conclused that, in relation to the film thickness, the material was approved by the specification, that demands that the highest thickness should be of 50 m. The setting time was longer than 10% advocate by the manufactures, however, once this time is not critical for root canal fillings, it would be viable to suggest the substitution for isoeugenol to the sealer if it is considered the analysed propertie.

Aim: To evaluate the long-term bond strength, degree of conversion and resistance to degradation in ethanol of HEMA-containing and HEMA-free model adhesive resins of a three-step etch-and-rinse adhesive system. Methods: The superficial dentin of 16 bovine incisor teeth was exposed, and the teeth were divided in two groups according to the HEMA concentration in the experimental adhesive (0% and 15%). In each tooth were made 6 cylindrical composite restorations. Half of the tooth restorations were submitted to microshear bond strength test after 24 h and the other half after 6 months. Degree of conversion of experimental resins was determined by Fourier transform infrared spectroscopy. Crosslink density was indirectly determined by the Knoop hardness of five specimens per group before and after immersion in ethanol for 6 h. Results: The group with 0% HEMA showed no difference in bond strength as compared to the group with 15% HEMA after 24 h or 6 months. There was no difference in degree of conversion and crosslink density between groups. Conclusions: HEMA content of the adhesive resin did not influence the bond strength to dentin, degree of conversion or resistance to degradation in ethanol.

The purpose of this study was to evaluate the influence of the internal standard peak on the measured degree of conversion (DC) for methacrylate-based resins analyzed by Fourier-transform infrared spectroscopy (FTIR). The influence of different baseline measurement methods was also determined. Different blends were prepared, mixing BisGMA/BisEMA and BisGMA/TEGDMA at proportions of 0% to 100%, in weight. Camphoroquinone and ethyl-4-dimethylamino-benzoate were used to permit the light activation of blends. Degree of conversion was evaluated using FTIR equipped with an attenuated total reflectance (ATR) device. Samples were dispensed onto ATR crystal and light activated for 40 s. The DC was calculated by relating the height of the peak 1637 cm-1 to the intensity of different internal standard peaks (1715, 1608, or 1582 cm-1), measured using two different baseline methods, before and after polymerization. Data were compared by ANOVA at 5% significance. The relationship between DC and monomer ratio was obtained by regression analysis. Double-bond conversion ranged from 32.75% to 78.50% for BisGMA/BisEMA blends, and from 32.75% to 76.22% for BisGMA/TEGDMA blends. For the BisGMA/BisEMA blends, the DC showed a linear association with the composition of the comonomer blends, independent of the internal standard peak and baseline method used. In contrast, the trends in DC for BisGMA/TEGDMA blends were different for each method of measurement. The internal standard peaks and measurement baseline should be taken into account when using FTIR to calculate the DC of methacrylate-based resins, especially comonomer blends containing a high degree of monomers that lack aromatic rings.

Várias pesquisas têm sido feitas com a finalidade de otimizar os métodos de polimerização das resinas acrílicas. Dentre as descobertas inclui-se a utilização da energia de microondas. Para as resinas acrílicas nacionais, os fabricantes preconizam um ciclo de polimerização alternado de 3 minutos em uma potência de 400W, 4 minutos a 0W e mais 3 minutos a 800W. Buscando simplificar ainda mais o processo de polimerização das resinas acrílicas, surgiu a proposta de um ciclo alternativo de 3 minutos a 500W. Sendo assim, o objetivo deste trabalho é analisar a eficácia deste novo ciclo, através do ensaio de resistência flexural, de acordo com a especificação n° 1567 da ISO, que requer um valor mínimo de 65MPa. Foram confeccionados 10 corpos de prova da resina acrílica termopolimerizável em microondas da marca Onda Cryl, divididos em dois grupos: o grupo controle (C), polimerizado de acordo com as orientações do fabricante e o grupo experimental (E), polimerizado por 3 minutos com 500W de potência. A partir dos testes realizados em uma máquina de ensaios obteve-se os seguintes resultados médios de resistência flexural em Mpa e respectivos desvios-padrão: C= 83,85 +- 6,51 e E= 89,72 +- 6,84. Com base nos resultados é lícito concluir que em relação à resistência flexural, a resina polimerizável em microondas Onda Cryl, pode ser polimerizada no ciclo reduzido de 3 minutos a 500W, uma vez que os resultados obtidos no presente estudo atenderam à especificação n° 1567 da ISO., Several researches have been done to optimize the methods of acrylic resin cure. Among the discoveries, the utilization of the microwave oven energy is included. For the Brazilian acrylic resins, the producers commend a cure cycle alternated from 3 minutes at 400W potency, 4 minutes at OW and 3 minutes at 800W. Trying to simplify even more the acrylic resin eure process, an alternative 3 minutes at 500W cyele is presented. The purpose of this study is to analyze this new cycle efficacy, through the flexural strength test, in agreement with the ISO specification number 1567, which requests a minimum value of 65Mpa. Ten specimens of acrylic resin therm-cured in the microwave oven of Onda Cryla brand, were made. They’re divided in two groups: the control group (C), cured in agreement to the producers orientations, and the experimental group (E), cured for 3 minutes at 500W of potency. The tests were made in a tests machine and the following medium results of flexural strength in MPa were obtained: C 83,85 (46,51) and E 89,72 (46,84). With the results, it’s licit to conclude that with regard to the flexural strength, the microwave cured resin Onda Cryla, can be cured in the reduced cycle from 3 minutes at 500W, once the results obtained with the present study attend to the ISO specification number 1567.

Objective The goal of this study was to determine the impact of an oral hygiene education programme for caregivers on the oral health of institutionalised elderly and to examine the effect of disability and low muscle strength on programme outcomes. Materials and methods The subjects of this study were geriatric patients (n = 80) from a nursing home. Katz Index for activities of daily living, handgrip strength and mucosal–plaque score (MPS) was evaluated at baseline and 1 year after intervention. The intervention consisted of an educational programme and specific guidelines for caregivers (to perform oral hygiene for dependent elderly and to supervise the independent elderly during oral hygiene practices). Differences on MPS were evaluated using a paired-sample t-test. A stratified analysis was carried out to identify differences in response to the programme according to the Katz Index and handgrip strength of elderly. Results The MPS was significantly reduced (p = 0.001) at follow-up; however, a separate analysis showed that only the independent elderly (p = 0.002) and those with normal muscle strength (p = 0.006) showed a reduction in MPS during the follow-up examination. Conclusion The oral hygiene education programme for caregivers resulted in a positive impact on oral hygiene of the independent and functional elderly.

Aim To develop and characterize a salicylate resin with potential use in bioactive endodontic sealers. Methodology Methyl salicylate, glycerol and titanium isopropoxide were added in a closed system for the transesterification reaction. The resin obtained was characterized by proton nuclear magnetic resonance spectroscopy (1H NMR) and size exclusion chromatography (SEC). To verify the applicability of the resin to the development of endodontic sealers, experimental cements were prepared by mixing glycerol salicylate resin, calcium hydroxide and methyl salicylate in the ratios of 2 : 1 : 1, 1 : 2 : 1, 1 : 1 : 2, 1 : 1 : 1, 4 : 1 : 1, 1 : 4 : 1 and 1 : 1 : 4. Setting times were measured according to ISO 6876. Features of the hardening reaction were described by micro-RAMAN spectroscopy. Results The transesterification reaction had a 72% efficiency. The 1H NMR analysis revealed the presence of the expected functional groups (hydroxyls and aromatic rings), and the SEC confirmed the molar mass of the resin produced. The setting times of experimental sealers ranged from 70 min (ratio 1 : 1 : 1) to 490 min (ratio 1 : 1 : 4). The conversion of the salicylic groups (1 613 cm−1) to salicylate salt (1 543 cm−1) and the reduction in calcium hydroxide peaks (1084 and 682 cm−1) were confirmed by micro-RAMAN spectroscopy, which showed the calcium chelation by the resin. Conclusion The new glycerol salicylate resin was successfully synthesized and revealed a potential application in the development of endodontic sealers.

Objective: To verify the influence of radiopaque fillers on an epoxy resin-based sealer. Material and Methods: Experimental sealers were formulated by adding 20%, 40%, 60%, 80%, 100% and 120% of calcium tungstate, ytterbium trifluoride or barium sulphate by weight to an epoxy-resin-base. Setting time, flow, film thickness, radiopacity, sorption, solubility, pH and push-out bond strength were evaluated. Results: The setting time ranged from 373 to 612.66 min, the flow varied from 13.81±0.49 to 22.49±0.37 mm, and the film thickness ranged from 16.67±5.77 to 33.33±11.54 µm. The lowest pH was 5.47±0.53, and the highest was 6.99±0.03. Radiopacity varied from 0.38±0.04 to 2.57±0.21 mmAl and increased with the amount of filler. Calcium tungstate sealers had a higher sorption and solubility than other sealers. There was no significant difference in the push-out bond strength among the fillers at the 120% concentration. CONCLUSION: The inorganic fillers evaluated and their concentrations affect the physicochemical properties of an epoxy resin-based root canal sealer.

Objective: The purpose of this study was to evaluate the physicochemical properties of acrylic resin polymerized by microwave energy in short cycle of polymerization.Methods: Two brands (Classico and VIPI) and two cycles were evaluated (manufacturer cycle and short cycle). The characteristics and properties as degree of conversion, glass transition temperature, impact strength-Izod, Knoop hardness, swelling degree, soluble fraction, specific mass, water sorption and solubility were evaluated.Results: Glass transition temperature, hardness, specific mass, soluble fraction and solubility were statistically significant between cycles and brands (p0.05) and impact strength presented difference between brands in short cycle (p0.05) e a resistência ao impacto no ciclo curto de polimerização foi diferente entre as marcas avaliadas (p

The aim of this study was to evaluate the physical properties of irreversible hydrocolloid materials poured immediately and after different storage periods. Four alginates were tested: Color Change (Cavex); Hydrogum (Zhermack); Hydrogum 5 (Zhermack); and Hydro Print Premium (Coltene). Their physical properties, including the recovery from deformation (n = 3), compressive strength (n = 3), and detail reproduction and gypsum compatibility (n = 3), were analyzed according to ANSI/ ADA specification no. 18. Specimens were stored at 23°C and humidity and were then poured with gypsum immediately and after 1, 2, 3, 4, and 5 days. The data were analyzed by two-way analysis of variance (ANOVA) and Tukey’s test at p < 0.05. All of the alginate impression materials tested exhibited detail reproduction and gypsum compatibility at all times. Hydro Print Premium and Hydrogum 5 showed recovery from deformation, as established by ANSI/ADA specification no. 18, after 5 days of storage. As the storage time increased, the compressive strength values also increased. Considering the properties of compounds’ recovery from deformation, compressive strength, and detail reproduction and gypsum compatibility, irreversible hydrocolloids should be poured immediately.

To evaluate the influence of several niobium pentoxide (Nb(2) O(5) ) concentrations on the radio-opacity, flow, film thickness, microhardness and degree of conversion of an experimental root canal sealer.An experimental dual-cured root canal sealer was produced with a methacrylate-based comonomer blend. Nb(2) O(5) was added at four different concentrations: 0, 80, 100 and 120 wt%. Radio-opacity was evaluated according to ISO 6876 using a digital system (n = 5). Flow and film thickness were determined in accordance with ISO 6876 (n = 3). Microhardness was evaluated with 50 g for 15 s (n = 5). Degree of conversion was evaluated with FTIR immediately after photocuring and after 1, 7 and 14 days. The data were analysed using anova and Tukey's test. The degree of conversion over time was evaluated using RM-anova (α = 0.05).The groups with 80 wt% and 100 wt% of filler showed no significant difference in radio-opacity from that of equivalent 2 mmAl (P0.05). The addition of 120 wt% resulted in radio-opacity values higher than 2 mmAl (P0.05). The flow was not significantly different amongst the different groups (P0.05). All groups had a film thickness of50 μm (ISO 6876). All groups with Nb(2) O(5) were associated with higher values of microhardness than the control group. The group with 0 wt% was associated with a higher degree of conversion at all times. All groups except those with 80 wt% had higher values for degree of conversion after 14 days than immediately after photocuring.The addition of Nb(2) O(5) increases radio-opacity and microhardness; this material may be a promising filler for the production of a new endodontic sealer.

OBJECTIVE: To evaluate the response of elastomeric ligatures in several colors for a 4 mm traction over time. METHODS: Morelli® elastomeric ligatures, were submitted to traction forces using two rods of circular cross section, until a 4 mm distance was reached, matching the approximate diameter of an upper central incisor bracket of the same manufacturer. The ligatures were kept in artificial saliva immersion at 37 ºC. Forces levels were measured immediately (0 h), 2, 4, 6, 8, 10, 12, 24, 48, 72, 96 hours, 1, 2, 3, 4 weeks and results were submitted to two-way repeated-measures ANOVA statistical analysis. RESULTS: The gray samples showed the higher initial values of tensile strength. The lowest values were presented by purple, light pink, green, black and red groups. The greater tensile strength instability was presented by red, black, silver, green and gray groups. The greater tensile strength stability was presented by deep pink, dark blue, blue, purple and light pink groups. CONCLUSION: Elastomeric ligatures do not present stable behavior when suffering traction forces over time and different colors display different behaviors. Deep pink, dark blue, blue, purple and light pink groups, displayed the most stable forces, suggesting that they should be used during the treatment to obtain constant forces.

The aim of this study was to evaluate the influence of applying 2% chlorhexidine for 30 seconds after phosphoric acid conditioning of dentin on the immediate and long-term bond strengths in deciduous teeth. The occlusal enamel was removed from 40 human sound deciduous molars, which were exfoliated by natural means, and the dentin was conditioned with 37% phosphoric acid for 15 seconds and washed with running water. The specimens were divided into two groups of 20 teeth. The test group received an application of 2% chlorhexidine for 30 seconds prior to a three-step etch-and-rinse adhesive system, whereas the control group received only the adhesive system. Three cylindrical restorations were made with a composite resin for each tooth. Ten teeth in each group were submitted to a microshear bond strength test after 24 hours, while the remaining teeth were stored in distilled water at 37 °C for 6 months before testing the microshear bond strength. The test group had a higher bond strength than did the control group after 6 months of storage. No statistical differences were found when groups with the same dentin treatment were compared at different times. Short applications of chlorhexidine at low concentrations prevent hybrid layer degradation and positively affect bond strength over time.

To evaluate the effect of variations in 2-hydroxyethyl methacrylate (HEMA) concentrations in an experimental comonomer blend on degree of conversion, water sorption, solubility, and ultimate tensile strength of adhesive resin.The effect of HEMA content (0, 15, 30, and 50%wt - control, G15, G30, and G50 groups, respectively) was tested in an experimental comonomer blend of bis-GMA, bis-EMA, TEG-DMA, and HEMA. The degree of conversion, polymerization rate, ultimate tensile strength, water sorption, and solubility of the adhesive resin blends were determined.At 40 s of light activation time, groups G30 and G50 showed a decrease of 30% and 61%, respectively, in degree of conversion compared to control. Water sorption and solubility differed for all groups, and was statistically higher in G50. For ultimate tensile strength, the control and G15 groups showed statistically higher values than the other groups (p0.05).Higher HEMA content increases dental adhesive resin degradation.

Objetivo: O objetivo deste estudo foi avaliar através da análise de sua ação bacteriostática e bactericida, a eficácia de uma solução de glutaraldeído 2% após receber sucessivas imersões de impressões de alginato, contaminadas. Materiais e métodos: Foram coletadas sete amostras do desinfetante em uso. A avaliação da ação bacteriostática, das amostras se deu pela presença de bactérias viáveis através do método de Contagem Padrão em Ágar. Para a avaliação da ação bactericida, placas foram inoculadas com Escherichia. coli, Pseudomonas aeruginosa, e Staphylococcus aureus. Poços com 0,9 cm de diâmetro, realizados no meio de cultura das placas, receberam alíquotas de 100L de glutaraldeído, de cada amostra. As placas foram mantidas entre 8-10C, por 16 horas para difusão do composto. Após as placas foram para estufa a 37C, por 24 horas. A atividade antibacteriana foi avaliada pela presença de zonas de inibição de crescimento bacteriano em torno dos poços onde o glutaraldeído foi colocado. Resultados: Os resultados mostram que não houve crescimento bacteriano em nenhuma amostra e que todas as placas inoculadas mostraram zona de inibição pela ação do glutaraldeído. Conclusão: O delineamento deste estudo permite concluir que pelo menos, 70 impressões de alginato podem ser desinfetadas em 3L de glutaraldeído 2%, durante 28 dias. Aim: The objective of this work is to evaluate the efficacy of 2% glutaraldehyde solution after successive immersions of contaminated alginate impressions by analyzing its bacteriostatic and bactericidal activity. Materials and methods: Seven samples of the disinfectant were collected. Evaluation of bacteriostatic activity of the samples was performed by observing the presence of viable bacteria through Standard Methods Agar (Plate Count Agar). Plates were inoculated with Escherichia. coli, Pseudomonas aeruginosa, e Staphylococcus aureus in order to evaluate bactericidal activity. Wells with a 0.9 cm diameter at the centre of the plate received aliquots of 100 μL of glutaraldehyde in each sample. Then, the plates were maintained at 8-10ºC for 16 hours to allow diffusion of the compound. Later, the plates were stored at 37ºC in a stove for 24 hours. Antibacterial activity was evaluated by the presence of zone of inhibition in bacterial growth around the wells where the glutaraldehyde was placed. Results: Results show no bacterial growth in any sample, and all inoculated plates showed zone of inhibition in bacterial growth. Conclusion: With this study design, it is possible to conclude that at least 70 alginate impressions may be disinfected in 3L of 2% glutaraldehyde solution during 28 days.

OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III) on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000) running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91) was significantly higher than that of AS (8.58±1.73) and XS (10.39±4.06) groups (p

Existem poucos dados sobre o conhecimento da população sobre saúde. Este estudo investiga o conhecimento em relação à saúde e ao uso de medicamentos e remédios por parte de pacientes ambulatoriais de uma Faculdade de Odontologia do Sul do Brasil. Para isso, foi usado um questionário que abordou questões relativas à saúde e ao uso e conhecimento de medicamentos. A amostra consistiu de 89 pacientes. A maioria deles (58,3%) considera que a origem das doenças que acometem a cavidade oral é de responsabilidade individual e/ou social. Mais da metade dos entrevistados (55,1%) relata seguir perfeitamente as orientações do prescritor. Menos da metade (44,9%) já usou medicamentos indicados por pessoa leiga. Apesar de estarem esperando por tratamento odontológico, 50,6% negaram ter problema de saúde. A maioria dos entrevistados (58,4%) não relata problemas em seguir uma prescrição. Entretanto, quando feitas questões induzidas, quase 80% da amostra apontaram dificuldades, como preço e efeitos adversos. Após análise dos dados observa-se a falta de conhecimento das pessoas em relação ao tema saúde, especialmente no que se refere a medicamentos., There are few studies about the population knowledge on health. This paper investigates the knowledge on health and use of medication and remedies in office patients of a Dental Faculty of Southern Brazil. A questionnaire which included questions related to health and use and knowledge of medications was used. The sample consisted of 89 patients. The majority of them (58.3%) believe that general diseases and oral diseases are caused by individual or social responsibility. Most patients (55.1%) refer to follow strictly the prescriptor’s instructions. Less than half of the interviewees (44.9%) had already taken medications indicated by laymen. Although the sample was awaiting for a dental appointment, 50.6% denied having any health problems. The majority of the interviewees (58.4%) did not report problems on following a prescription. However, when they were given choices, almost 80% of the sample reminded hindrances as price and side effects. After analyzing the data we can observe the lack of knowledge of people in relation to the subject health, especially medication.

Objective: The objective of this study was to evaluate the behavior of intra-arch latex elastic of different brands and colors when subjected to disinfection procedures. Methods: A total of 320 units of American Orthodontics elastic; Morelli and Uniden were selected and divided into four groups according to the performed disinfection process: autoclave - 15 minutes; hypochlorite - 20 minutes; glutaraldehyde - 30 minutes and control. The disinfecting agents and the disinfection time were defined by a prior microbiological test. Before and after disinfection, by means of a universal trial machine, the maximum generated strength – until the rupture occurred – was evaluated. Results: The autoclave disinfection reduced significantly the strength generated by elastic, in 75% of the brands. The disinfection in hypochlorite increased significantly the strength generated by Morelli elastic; probably the alteration to its elastic property increased its rigidity. Neither the Yellow Uniden nor the American elastic suffered any significant reduction in strength as the result of hypochlorite disinfection. The glutaraldehyde was the disinfectant solution with less significant effect on the strength of the bands, affecting only the Green Uniden. Conclusion: The results suggest that the 2% glutaraldehyde is the disinfectant less aggressive to the elastic performance.

Durante o processo de moldagem, o alginato é contaminado com saliva, placa e eventualmente com sangue, meios que podem conter microrganismos e, assim, constituem um risco de contaminação cruzada entre pacientes e profissionais da Odontologia. Sendo assim, faz-se necessária a adoção de um método de desinfecção eficaz. A proposta deste trabalho foi avaliar a eficácia antibacteriana das soluções de glutaraldeído (2%) e hipoclorito de sódio (2%) na desinfecção dos moldes de alginato, durante imersão de 10 min, comparando-as com a lavagem em água e moldagem controle. A avaliação se deu pela turvação do meio de cultura e confecção de lâminas para análise microscópica. Os resultados mostraram que dos 48 corpos de prova de alginato obtidos após moldagem de 12 pacientes, aqueles lavados em água por 10 s, ou incluídos diretamente no meio, apresentaram proliferação bacteriana, enquanto que os submetidos à desinfecção química não provocaram contaminação nos meios de cultura, comprovando a eficácia dos desinfetantes., During impression taking with alginate, the material is contamined with saliva, plaque and eventually blood which might contain micro organisms and might provide a significant source for cross-contamination in the dental practice. There foreitis necessary to adopt an efficient method of disinfection avoid this risk. The purpose of this research was to evaluate the efficacy of glutaraldehyd (2%)and sodium hypochlorite(27) in the disinfection of alginate impressions through 10 min of immersion. The evaluation was maid by the turbidity of the culture medium and microscopic analysis. The results showed that, from the 48 specimen of alginate,those which were washed in water for 10 s, or included in the culture medium immediately after impression showed bacterian growth. The specimen that were immersed in disinfecting solution did not present bacterian growth in the culture medium, proofing the efficacy of the disinfectants.

O objetivo desta pesquisa foi avaliar, in vitro, a influência do tipo de adesivo na resistência de união de “brackets” metálicos colados ao esmalte de dentes humanos. Trinta molares humanos extraídos foram incluídos em tubos de PVC e aleatoriamente divididos em três grupos (n=10): Grupo I – “bracket” colado com Transbond (3M/Unitek), Grupo II – “bracket” colado com AdheSE (Ivoclar/Vivadent) e Grupo III – “bracket” colado com Xeno III (Dentsply). O preparo da superfície de esmalte foi realizada profilaxia, seguido da aplicação dos adesivos conforme instruções dos fabricantes. Os “brackets” metálicos (Morelli®) foram colados na porção central de cada fragmento com resina fotoativada Transbond XT (3M/Unitek). Os corpos-de-prova foram armazenados em água destilada a 37ºC durante 24 horas. Em seguida, foram submetidos ao teste de cisalhamento em máquina de ensaio universal (EMIC, DL 2000), com velocidade de 1 mm/minuto e ao Índice de Adesivo Remanescente (IAR). A análise estatística (ANOVA/Tukey) demonstrou que o fator adesivo não influencia a resistência de união ao cisalhamento. Dessa forma, os adesivos autocondicionantes são uma boa alternativa para a colagem de “brackets” metálicos. The aim of this in vitro study was evaluate the influence of the adhesive type in the shear bond strength of metallics brackets to the dental enamel. Thirty molars human were placed into PVC rings and randomly divided into three groups (n=10). Group I - bracket bonded with Transbond (3M/Unitek), Group II – bracket bonded with AdheSE (Ivoclar/ Vivadent) and Group III – bracket bonded with Xeno III (Dentsply). The enamel surface was subjected to prophylaxis, followed by application of the adhesive systems, accor-ding to the manufacturer’s recommendations. The metallic brackets (Morelli®) were bonded in the central portion of the fragments with light-cure resin Transbond XT (3M/ Unitek). The specimens were stored in distilled water at 37ºC for 24 hours. The samples were then submitted to shear bond strength in a universal testing machine EMIC DL2000 at a cross-head speed of 1 mm/minute and Index of Remainder Adhesive (ARI). The statistical analyses (ANOVA/ Tukey) showed the adhesive system didn’t influence the shear bond strength. In that way, the self-etching primers are a good alternative for the metallic brackets bonding.

Aim: To evaluate influence of three different filler particles on an experimental Bisphenol A ethoxylated dimethacrylate (Bis-EMA) based root filling material. Materials and Methods: Resin-based endodontic sealers were produced using Bis-EMA, camphorquinone, ethyl 4-dimethylaminobenzoate (EDAB), N, N-dihydroxyethyl-p-toluidine (DHEPT), butylated hydroxytoluene (BHT), and benzoyl peroxide. The experimental groups were formulated adding 10, 20, 30, 40, and 50% of calcium tungstate (CaWO 4 ), ytterbium trifluoride(YbF 3 ), and tantalum oxide(Ta 2 O 5 ). Flow, thickness, and radiopacity tests were conducted in accordance with ISO 6876. Sorption and solubility (SL) tests were conducted in accordance with ISO 4049, pH was measured with a pH meter, and degree of conversion (DC) was evaluated with Fourier transform infrared spectroscopy (FTIR). For radiopacity, two-way analysis of variance (ANOVA) and Tukey«SQ»s multiple comparison test was performed. For DC analysis, one-way ANOVA and Tukey«SQ»s multiple comparison test was performed. All statistical analyses were performed with a significance level of 5%. Results: All groups showed lower flow with increased filler concentration. All groups showed film thickness values lower than 50μm, as ISO recommends, except CaWO 4 50% group (76.7μm). pH values varied from 5.95 (± 0.07) in YbF 3 40% group to 6.90 (± 0.07) in Ta 2 O 5 40% group. In the radiopacity test, YbF 3 30%, Ta 2 O 5 40%, and Ta 2 O 5 50% groups showed no statistical significant difference to 3mmAl. Ta 2 O 5 and YbF 3 groups in 10, 20, and 30% concentrations presented sorption and SL values as ISOrecommendation. Addition ofTa 2 O 5 and CaWO 4 decreased DC after 14 days. YbF 3 addition showed no difference in DC from control group. Conclusion: YbF 3 filler addition promoted higher properties compared to CaWO 4 and Ta 2 O 5 on Bis-EMA based root canal sealer.

A proposta deste trabalho foi avaliar a eficácia de meios para armazenagem de resíduos de amálgama, no sentido de reduzir a liberação de mercúrio para o ar ambiente, tendo em vista o valor teto preconizado pela NR-15, da Portaria número 3214, de 8 de junho de 1978, do Ministério do Trabalho do Brasil. Como fonte de mercúrio foi utilizado o amálgama em cápsula da marca Dispersalloy (Dentsplay). Após a trituração mecânica, o amálgama foi passado através de uma peneira com malha de 1,00 mm a fim de padronizar a fragmentação do mesmo. O amálgama fragmentado foi armazenado em potes de polipropileno transparente, com 0,5 L de capacidade volumétrica, onde, em um dos potes fragmentos foram mantidos a seco (grupo 1), e nos demais foram imersos em água destilada (grupo 2), em glicerina (grupo 3) e na solução de fixador para radiografia odontológica (grupo 4). Cada um dos quatro potes foram mantidos hermeticamente fechados, e colocados dentro de outro recipiente de polipropileno. Trinta minutos após a armazenagem dos fragmentos, os potes foram abertos, e iniciou-se a coleta de amostras de ar ao redor de cada um dos quatro potes. O mesmo procedimento foi realizado 30 dias após a armazenagem inicial. Para a coleta de ar foi utilizada a Bomba Amostragem de Ar, da marca SKCO. As amostras de ar foram analisadas através de espectrofotometria de absorção atômica, para quantificação de mercúrio. A análise mostrou as seguintes concentrações de mercúrio nas amostras de ar, da primeira coleta e da segunda, para os grupos, respectivamente: grupo I - 6,100 mg/m3 e 0,816 mg/m3; grupo 2 - 0,252 mg/m3 e 0,157 mg/m3; grupo 3 0,071 e 0,0XX mg/m3; grupo 4 - 0,256 mg/m3 e 0,005 mg/m3. Os resultados mostraram ser a glicerina o meio de armazenagem mais seguro, visto que a quantidade de vapor de mercúrio encontrado no ar, tanto na coleta inicial como após 30 dias, jamais ultrapassou o valor teto preconizado pela NR-15, conferindo maior segurança, desde o período inicial da armazenagem destes resíduos., The purpose of this study was to evaluate the shown efectiveness by different ways of storage of amalgam residues, to reduce the liberation of mercury from such residues to the air ambience and to compare with lhe highest value established by the NR-15 (regulation norm number 15) from the decroe number 3214, of the brazilian labor ministry, dated from june, 8 h of 1978. As mercury source, amalgam in capsules of the brand Dispersalloy (Dentsplay) was used after grinding, in the mechanic amalgamizer varimix II (caulk), the quantity of amalgam in cach capsule was collected from a sieve that had a mesh with mm of width to standardize lhe fragmentation. The fragmented amalgam was stored in jars made of transparent polypropylene, that could store 5()() ml; one of the jars was kept in a dry atmosphere (group l), and the others were immersed in distilled water (group 2), in glycerin (group 3) and in a solution of dentistry x-ray fixer (group 4). These jars were kept tightly shut, and put inside a bigger polypropylene recipient, during the time they were stored. Thirty minutes after the storage of the fragments, the jars were opened and air samples were collected around each of the four jars. The same procedure was performed 30 days after the initial storage. A Pump Sampler of Air manufactured by SKCâ was used to do the air collection. The air samples were analyzed by a spectrophotorneter of atomic absorption, to determinate the quantity of mercury. This analysis showed the following mercury concentration rates in the air samples, from the first and the second collection of the four groups, in the following order: group I 6,100 mg/m3 and 0,816 mg/m3 ; group 2 - 0,252 mg/rn3 and 0,157 mg/m 3 ; group 3 — 0,071 mg/m3 and 0,005 mg/m3 ; groui) 4 — 0,256 mg/m3 and 0,005 mg/m3. The results showed that glycerin is the safest way to store amalgam residues, since the quantity of mercuor vapor found in the air, in both collections: the first one and the other 30 days after, never surpassed the highest value established by NR-15 (Regulation Norm number 15), also demonstrating, bigger security, since the initial period of storage of these residues.

The aim of this study was to evaluate the porosity of acrylic heat cured resins related the time elapsed from packing to polymerization. The results indicated that the mixtures to rage for a period of two weeks is considered secure considering the risks of porosity in the acrylic resin only if all recommendations procedures observed, as well as the correct handling., O objetivo deste trabalho foi avaliar a porosidade das resinas acrílicas de termo-polimerização em função do tempo decorrido entre a inclusão e a polimerização. Os resultados mostraram que a armazenagem da mistura por um período de até duas semanas pode ser considerado seguro quanto aos riscos de porosidade na resina acrílica desde que sejam observadas todas as recomendações e mantidos todos os cuidados requeridos por uma técnica correta de manipulação das resinas acrílicas de termo-polimerização.

O objetivo dêsle trabalho foi avaliar a alteração dimensional dê uma liga de gálio e compeftá-la os resurtados rnosraÍam que os aman"iT'Xï3liJl3iiiXFp3lìÉ9?iïi; 1 da Associação DêntáÍia AmêÍicena e Grupo BÍasileiro de Materiais DentáÍios, que permitem uma alteração dimensional de 0 + 20 pÍÍúcm. O mesmo não ocoreu oom a lige de gálio quê mostrou uma expansão de 27,38 pm/cm. The objective of this work was to evaluate the dimensional alteration of a gallium alloy and to complement it the results show that the dimensional alteration of the Ameícene Dental Association and Biasile Group of Dental Materials allow a dimensional alteration. + 20 μm/cm The same did not occur with the gallium alloy which showed an expansion of 27.38 μm/cm.

The purpose of this study was to evaluate, "in vitro" the effect of the adhesive resin cement lining (Panavia EX) in reducing microleakage of amalgam restorations with or without a enamel acid etching treatment. Thirty human teeth with class V cavity preparations were divided in three groups and restored as folows: group A - the teeth were restored with amalgam only; group B - one layer of Panavia EX was applied to the cavities before the restoration; and group C - the enamel of the cavity margins were acid etched, the cavity walls protected with Panavia EX and then restored. The teeth were then immersed in a solution of methylene blue. The analysis of the results indicated that: a) all the amalgam restorations without Panavia EX showed important microleakage (70% severe and 30% moderate); b) the restorations protected with Panavia EX showed reduced microleakage when compared with the control (group A); c) the acid etching did not influence the microleakage results., O objetivo deste trabalho foi avaliar "in vitro" o efeito do cimento adesivo Panavia EX na microinfiltração de restaurações de amálgama. Trinta dentes humanos com cavidades classe V foram divididos em 3 grupos e restaurados da seguinte forma: no grupo A todas as cavidades foram restauradas apenas com amálgama; no grupo B uma camada de Panavia EX foi aplicada às paredes cavitárias antes da restauração e no grupo C, o esmalte do contorno da cavidade foi condicionado com ácido, as paredes da cavidade protegidas com Panavia EX e então restauradas com amálgama. Os dentes foram imersos numa solução de azul de metileno e os resultados indicaram que: a) todas as restaurações de amálgama sem Panavia EX mostraram infiltração severa e moderada; b) as restaurações forradas com Panavia EX tiveram reduzida infiltração quando comparadas com o controle (Grupo A); e, c) não houve influência do condicionamento ácido quanto à infiltração marginal.

Orthodontic treatment with fixed brackets plays a major role on the formation of white spot lesions. Objective This study aimed to incorporate silver nanoparticle solutions (AgNP) in an orthodontic adhesive and evaluate its physicochemical and antimicrobial properties. Material and Methods Silver nanoparticle solutions were added to a commercial adhesive in different concentrations (w/w): 0%, 0.11%, 0.18%, and 0.33%. Shear bond strength (SBS) test was performed after bonding metal brackets to enamel. Raman spectroscopy was used to analyze in situ the degree of conversion (DC) of the adhesive layer. The surface free energy (SFE) was evaluated after the measurement of contact angles. Growth inhibition of Streptococcus mutans in liquid and solid media was determined by colony-forming unit count and inhibition halo, respectively. One-way ANOVA was performed for SBS, DC, SFE, and growth inhibition. Results The incorporation of AgNP solution decreased the SBS (p