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Dental plaque is a biofilm composed of a complex oral microbial community. The accumulation of plaque in the pit and fissures of dental elements often leads to the development of tooth decay (dental caries). Here, potent anti-biofilm materials were developed by incorporating zinc methacrylates or di-n-butyl-dimethacrylate-tin into the light-curable sealant and their physical, mechanical, and biological properties were evaluated. The data revealed that 5% di-n-butyl-dimethacrylate-tin (SnM 5%) incorporated sealant showed strong anti-biofilm efficacy against various single-species (Streptococcus mutans or Streptococcus oralis or Candida albicans) and S. mutans-C. albicans cross-kingdom dual-species biofilms without either impairing the mechanical properties of the sealant or causing cytotoxicities against mouse fibroblasts. The findings indicate that the incorporation of SnM 5% in the experimental pit and fissure self-adhesive sealant may have the potential to be part of current chemotherapeutic strategies to prevent the formation of cariogenic oral biofilms that cause dental caries.

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OBJECTIVE: The purpose of this study was to characterize and to evaluate the bioactivity potential of experimental root canal sealers (ES) based on Portland cement, epoxy resin with nano- and micro-particles of niobium or zirconium oxide used as radiopacifiers in comparison to AH Plus and MTA Fillapex. METHODS: Specimens of the sealers (10 mm in diameter×1 mm thick) were prepared and the radiopacity was evaluated according to ISO 6876 (2012) specifications. Characterization of the sealers was performed under the scanning electron microscope (SEM) immediately after setting and after immersion for 28 days in Hank's balanced salt solution (HBSS). In addition X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy were also performed. The pH and calcium ion release were measured after 1, 7, 14, 21 and 28 days after completion of seating using a digital pH meter and an atomic absorption spectrophotometer, respectively. RESULTS: The experimental sealers exhibited an average radiopacity of 2.5 mm thickness of aluminum, which was similar to MTA Fillapex (P>0.05) and inferior to AH Plus (P<0.05). AH Plus did not show bioactivity. Although the experimental sealers did not exhibit the formation of hydration product, they encouraged the deposition of crystalline spherical structures of calcium deficient phosphate. The highest pH and calcium release values were observed with the experimental sealers (P<0.01). ES-Nb-micro was the only sealer to present hexagonal shaped crystal deposition. SIGNIFICANCE: Novel root canal sealers based on a mixture of Portland cement, epoxy resin and radiopacifier exhibited a degree of bioactivity although no evidence of cement hydration was demonstrated on material characterization. The radiopacifier particle size had limited effect on the sealer microstructure and chemical properties.

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A aplicação de selantes de superfície, através da penetração nas irregularidades superficiais e na interface dente/restauração, é realizada ao final do procedimento restaurador e pode minimizar algumas limitações, prolongando a longevidade clínica das restaurações de resina composta. Este estudo clinico randomizado se propôs a avaliar o efeito da aplicação de um selante de superfície no comportamento clínico de restaurações posteriores de resina composta do tipo classe I. Vinte e sete pares de dentes molares ou pré-molares, superiores ou inferiores, que apresentavam lesões de cárie (classe I) ou restaurações de amálgama ou resina composta (classe I) insatisfatórias, que necessitavam de substituição completa, foram aleatorizados e preparados e restaurados com a resina composta Esthet-X. Sobre a superfície da resina de apenas um dente de cada par foi aplicado o selante de superfície Lasting Touch utilizando o modelo experimental de boca dividida. A avaliação única foi realizada empregando-se o método direto USHPS modificado, nos tempos: baseline, 6 meses, 12 meses, por dois operadores. Radiografias interproximais e réplicas das faces oclusais foram obtidas por meio da moldagem com silicona de adição e vazadas com resina epóxica para avaliação qualitativa com Microscópio Eletrônico de Varredura. Os dados foram submetidos ao teste de Mc Nemar (p<0,05). Para a integridade marginal, após 6 meses de avaliação, apenas 1 (4%) restauração do grupo com selante de superfície recebeu o escore Bravo. Aos 12 meses, a integridade marginal apresentou 1 (4%) do grupo sem selante e 2 (7%) restaurações com selante com escore Bravo. Os resultado apresentados nos períodos de avaliação não apresentaram diferenças estatisticamente significantes (p=1,0, para todas as condições. Não houve diferença no desempenho clínico de restaurações de resina composta com e sem selante de superfície, sendo aceitáveis após 12 meses de avaliação. As observações em MEV demonstraram...

The finishing, polishing and surface sealant application, by superficial irregular penetration and between restoration interface, are applied at the end of the restoration and decrease these limitations, and extend the clinical longevity of composite resin restorations. This clinical randomized controled study however aimed to evaluate the effect of the surface sealant application in the clinical behavior of composite posterior resin class I restorations. Twenty seven pairs of upper or lower molars or premolars with carious lesions (class I), and unsatisfactory amalgam or composite resin restorations, which needed total replacement, were randomized and prepared and restored with Esthet X composite resin. The composite resin surface of one tooth from each pair was covered with Lasting Touch surface sealant (Split Mouth Design). The clinical evaluation was made by using the modified direct method USPHS, at the following times: baseline, 6 months and 12 months, by two different operators. Bitewing radiographs and replicas of the occlusal surfaces were obtained by using a silicone impression material poured with epoxy resin for the qualitative evaluation with Scanning Electron Microscopy. The data was analyzed with the McNemar test (p <0.05). Results showed that for the marginal integrity, after 6-month evaluation, only 1 (4%) sealed restoration had a Bravo rating. At the end of 12 months, the marginal integrity showed 1 (4%) sealed restoration and 2 (7%) non sealed Bravo restorations. Results at all evaluations periods did not show statistical significant differences (p=1.0) for all conditions. There was no difference in the clinical performance of the composite resin restorations (Esthet X) with or without the surface sealant (Lasting Touch), demonstrated good behavior after 12 months. Based on SEM examinations, the surface sealant application promoted a regular and smooth surface, for all the evaluation times. In a 12 months evaluations period, the surface...

Assuntos

RESUMO

A aplicação de selantes de superfície, através da penetração nas irregularidades superficiais e na interface dente/restauração, é realizada ao final do procedimento restaurador e pode minimizar algumas limitações, prolongando a longevidade clínica das restaurações de resina composta. Este estudo clinico randomizado se propôs a avaliar o efeito da aplicação de um selante de superfície no comportamento clínico de restaurações posteriores de resina composta do tipo classe I. Vinte e sete pares de dentes molares ou pré-molares, superiores ou inferiores, que apresentavam lesões de cárie (classe I) ou restaurações de amálgama ou resina composta (classe I) insatisfatórias, que necessitavam de substituição completa, foram aleatorizados e preparados e restaurados com a resina composta Esthet-X. Sobre a superfície da resina de apenas um dente de cada par foi aplicado o selante de superfície Lasting Touch utilizando o modelo experimental de boca dividida. A avaliação única foi realizada empregando-se o método direto USHPS modificado, nos tempos: baseline, 6 meses, 12 meses, por dois operadores. Radiografias interproximais e réplicas das faces oclusais foram obtidas por meio da moldagem com silicona de adição e vazadas com resina epóxica para avaliação qualitativa com Microscópio Eletrônico de Varredura. Os dados foram submetidos ao teste de Mc Nemar (p<0,05). Para a integridade marginal, após 6 meses de avaliação, apenas 1 (4%) restauração do grupo com selante de superfície recebeu o escore Bravo. Aos 12 meses, a integridade marginal apresentou 1 (4%) do grupo sem selante e 2 (7%) restaurações com selante com escore Bravo. Os resultado apresentados nos períodos de avaliação não apresentaram diferenças estatisticamente significantes (p=1,0, para todas as condições. Não houve diferença no desempenho clínico de restaurações de resina composta com e sem selante de superfície, sendo aceitáveis após 12 meses de avaliação. As observações em MEV demonstraram...

The finishing, polishing and surface sealant application, by superficial irregular penetration and between restoration interface, are applied at the end of the restoration and decrease these limitations, and extend the clinical longevity of composite resin restorations. This clinical randomized controled study however aimed to evaluate the effect of the surface sealant application in the clinical behavior of composite posterior resin class I restorations. Twenty seven pairs of upper or lower molars or premolars with carious lesions (class I), and unsatisfactory amalgam or composite resin restorations, which needed total replacement, were randomized and prepared and restored with Esthet X composite resin. The composite resin surface of one tooth from each pair was covered with Lasting Touch surface sealant (Split Mouth Design). The clinical evaluation was made by using the modified direct method USPHS, at the following times: baseline, 6 months and 12 months, by two different operators. Bitewing radiographs and replicas of the occlusal surfaces were obtained by using a silicone impression material poured with epoxy resin for the qualitative evaluation with Scanning Electron Microscopy. The data was analyzed with the McNemar test (p <0.05). Results showed that for the marginal integrity, after 6-month evaluation, only 1 (4%) sealed restoration had a Bravo rating. At the end of 12 months, the marginal integrity showed 1 (4%) sealed restoration and 2 (7%) non sealed Bravo restorations. Results at all evaluations periods did not show statistical significant differences (p=1.0) for all conditions. There was no difference in the clinical performance of the composite resin restorations (Esthet X) with or without the surface sealant (Lasting Touch), demonstrated good behavior after 12 months. Based on SEM examinations, the surface sealant application promoted a regular and smooth surface, for all the evaluation times. In a 12 months evaluations period, the surface...

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This study evaluated the sealing ability of gray MTA-Angelus mixed with propyleneglycol in furcal perforations using a bacterial leakage test. Furcal perforations were created in 30 human mandibular molars using a size 3 round bur The samples were divided randomly into 2 experimental groups (n=10) according to the mixing agent. In G1, the MTA powder was mixed with propyleneglycol, while distilled water was used in G2. A 3:1 powder-liquid ratio was used for both groups. The MTA was placed in the perforation with an MTA carrier and condensed with hand pluggers. Non-repaired (n=5) and totally sealed (n=5) perforations served as positive and negative controls, respectively. Bacterial leakage was assessed daily for 30 days in a double-chamber apparatus with Enterococcus faecalis. Data were analyzed using Fisher exact test (p < 0.05) for three leakage periods: 1st to 10th day (P1); 11th to 20th day (P2); and 21st to 30th day (P3). The positive control presented leakage in all specimens within the first 24 hours, while no leakage was observed in the negative control during the experimental period. Leakage was observed in five (50%) of the 10 samples of the propyleneglycol group (G1) and seven (70%) of the distilled water group (G2) by the 20th day, without significant difference between the groups in periods P1 and P2 (p = 0.137). The leakage was significantly lower for G1 than G2 in period P3 (50% versus 100%, respectively, p = 0.016). In this single aerobic bacterial leakage method, the use of propyleneglycol as a vehicle for gray MTA-Angelus increased its sealing ability in furcal perforations at the end of the 30-day experimental period.

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PURPOSE: The aim of the present study was to perform a review of the effects of infiltrants and sealers on the inhibition of enamel demineralisation. MATERIALS AND METHODS: The authors searched the Cochrane Library, Embase, PubMed and Web of Science (ISI) for papers published between January 1970 and September 2008. The main search terms were 'artificial caries' or 'caries treatment' or 'caries-like lesion' or 'white spot lesion' or 'enamel demineralisation' or 'natural caries' and 'enamel' and 'sealant' or 'resin infiltration'. The inclusion criteria were studies that produced artificial non-cavitated enamel lesions before the application of sealant in in vivo or in vitro studies. Studies excluded were those that had not produced artificial non-cavitated enamel lesions before the application of sealant; had evaluated the inhibition of enamel demineralisation around restorations, sealant and orthodontic bracket/bands; had not evaluated the inhibition of enamel demineralisation after the sealant application; and had not applied sealant materials. Selected papers were given scores, from A to C, according to predetermined criteria. RESULTS: Eighteen studies were identified and included in the project critical appraisal. Two papers were classified as Grade A, nine as Grade B and seven as Grade C. CONCLUSIONS: It can be concluded that while fissure sealing acts as a diffusion barrier on the top of the lesion surface, the infiltration technique creates a barrier inside the lesion by replacing the mineral lost with a low-viscosity light-curing resin.

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This study evaluated the sealing ability of gray MTA-Angelus mixed with propyleneglycol in furcal perforations using a bacterial leakage test. Furcal perforations were created in 30 human mandibular molars using a size 3 round bur. The samples were divided randomly into 2 experimental groups (n=10) according to the mixing agent. In G1, the MTA powder was mixed with propyleneglycol, while distilled water was used in G2. A 3:1 powder-liquid ratio was used for both groups. The MTA was placed in the perforation with an MTA carrier and condensed with hand pluggers. Nonrepaired (n=5) and totally sealed (n=5) perforations served as positive and negative controls, respectively. Bacterial leakage was assessed daily for 30 days in a double-chamber apparatus with Enterococcus faecalis. Data were analyzed using Fisher exact test (p<0.05) for three leakage periods: 1st to 10th day (P1); 11th to 20th day (P2); and 21st to 30th day (P3). The positive control presented leakage in all specimens within the first 24 hours, while no leakage was observed in the negative control during the experimental period. Leakage was observed in five (50%) of the 10 samples of the propyleneglycol group (G1) and seven (70%) of the distilled water group (G2) by the 20th day, without significant difference between the groups in periods P1 and P2 (p=0.137). The leakage was significantly lower for G1 than G2 in period P3 (50% versus 100%, respectively, p=0.016). In this single aerobic bacterial leakage method, the use of propyleneglycol as a vehicle for gray MTAAngelus increased its sealing ability in furcal perforations at the end of the 30-day experimental period.

Este estudo avaliou a capacidade de selamento do MTA-Angelus cinza manipulado com propilenoglicol em perfuracoes de furca usando um teste de infiltracao bacteriana. Perfuracoes de furca foram criadas em 30 molares inferiores usando uma broca esferica numero 3. As amostras foram divididas aleatoriamente em dois grupos experimentais (n=10) de acordo com o agente de manipulacao. Em G1, o po do MTA foi manipulado com propilenoglicol enquanto que a agua destilado foi utilizada no G2. A proporcao po-liquido de 3:1 foi usada para ambos os grupos. O MTA foi colocado na perfuracao com uma porta- MTA e condensado com condensadores manuais. Perfuracoes nao-reparadas (n=5) e totalmente impermeabilizadas (n=5) serviram como controle positivo e negativo, respectivamente. A infiltracao bacteriana foi verificada diariamente durante 30 dias em um aparato de dupla camara com Enterococcus faecalis. Os dados foram analisados pelo teste exato de Fisher (p<0,05) para tres periodos: 1o ao 10o dia (P1), 11o ao 20o dia (P2) e do 21o ao 30o dia (P3). O controle positivo apresentou infiltracao em todas as amostras nas primeiras 24 horas, enquanto nenhuma infiltracao foi observada no controle positivo durante o periodo experimental. Infiltracao foi observada em 5 (50%) das 10 amostras do grupo do propilenoglicol (G1) e 7 (70%) do grupo da agua destilada no 20o dia, sem diferenca significativa entre o grupos nos periodos P1 e P2 (p=0,0137). A infiltracao foi significantemente menor para G1 que para G2 no periodo P3 (50% versus 100%, respectivamente, p=0,016). Neste metodo de infiltracao de apenas uma bacteria aerobica, o uso do propilenoglicol como veiculo para o MTA-Angelus cinza aumentou sua capacidade de selamento em perfuracoes de furca no final do periodo experimental de 30 dias.

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An analysis was carried out to observe whether the application or not of a composite surface sealant (CSS), as well the moment for CSS application were able to reduce marginal microleakage in compactable composite resin restoration. All the preparations were restored with a compactable composite resin. The restored teeth were randomly assessed. G1 (control group): finished and polished; G2: finished, polished, etched and cover with CSS; G3: immediately after the restoration done the CSS was applied, then finished and polished; G4: CSS applied immediately after the restoration was done, the finished and polished, etched, and covered with CSS. The specimens were isolated with nail polish, thermocycled, immersed in aqueous solution of silver nitrate, and followed in a photo developing solution. The microleakage scores obtained from the occlusal and cervical walls were analyzed with the Kruskall-Wallis nonparametric test. No microleakage was found at the enamel margins. Comparing the microleakage scores at dentin/cementum margins (p < 0.05) it was found that G3 (p = 0.0162) and G4 (p = 0.0187) were able to reduce microleakage when compared with group G2. However the results were not statistically different from the control group. The application of CSS was not able to completely eliminate marginal microleakage at the dentin/cementum margins.

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This work evaluated the remineralization of demineralized enamel of pits and fissures of human third molars sealed with a glass ionomer cement (Fuji IX, GC Corporation--Japan) or with a Bis-GMA sealant (Delton--Dentsply). Ten volunteers participated in this in situ study that consisted of two thirty-day periods using intra-oral devices, with a weeks interval in between. Four experimental treatment procedures and one control were randomly assigned to the volunteers specimens: Group I, no treatment, control; Group II, artificial caries process; Group III, same treatment as Group II, but sealed with Delton (Dentsply); Group IV, same treatment as Group II, but sealed with Fuji IX (GC Corporation--Japan); Group V, same treatment as Group II and no sealing. Groups I and II were not submitted to the oral environment and served as controls. After a period of 30 days in the oral environment, the specimens were removed from the devices, embedded in acrylic resin, ground flat and polished. Then, Knoop hardness tests were performed, with a 25 g static load applied for 15 seconds. The measurements were made from the base of the fissure up to an opening of 600 microm, pre-established between the inclines of the cusps. Three indentations were then made, located at 25, 75, and 125 microm in depth from the outer enamel margin and 100 microm apart from each other (Micromet 2003). The Brieger F and Bonferronis tests were applied to the measurements. It was concluded that sealing with the glass ionomer cement Fuji IX was capable of making the enamel of pits and fissures more resistant by increasing the value of Knoop hardness.

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