Dentifrício fluoretado suplementado com hexametafosfato de sódio sobre o processo de desmineralização do esmalte: estudos in vitro e in situ

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação in vitro do efeito das tinturas de Camellia sinensis e de Aloe arborescens na remineralização de lesão de cárie artificial em esmalte dentário humano

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de uma nova liga quaternária Ti25Ta25Nb3Sn para aplicações odontológicas

Pós-graduação em Engenharia Mecânica - FEG

Efeito de soluções fluoretadas contendo xilitol e sorbitol no número de estreptococos do grupo mutans na saliva de seres humanos

The objective of this study was to assess the effect of 0.05% sodium fluoride solutions containing 2.5% or 12.5% xylitol on the number of Streptococcus mutans in the human mouth. Fifty boys between 8 and 16 years of age participated in this double-blind crossover study. Of the original 50 boys, 33 finished the study. Participants were randomly divided into four groups. The following solutions were employed: placebo solution; 0.05% sodium fluoride solution; 0.05% sodium fluoride + 2.5% xylitol + 2% sorbitol; 0.05% sodium fluoride + 12.5% xylitol + 2% sorbitol. Each solution was used for a 28-day period (20 mL/day, twice a day), with a 10-day washout period between solutions. There were no significant differences (P = 0.32) between the two xylitol-containing solutions (2.5% vs. 12.5%) concerning the number of Streptococcus mutans. However, there was a significant difference between these two xylitol-containing solutions and the sodium fluoride and placebo solutions (P < 0.001). Our results suggest that the 0.05% sodium fluoride solutions containing either 2.5% or 12.5% xylitol caused a significant reduction in the number of Streptococcus mutans.

Anticariogenic potencial of acidulate solutions with low fluoride concentration

Objetives: The aim of this study was to verify the anticariogenic effect of acidulate solutions with low NaF concentration, using pH-cycling model and bovine enamel. Material and Methods: Enamel blocks were submitted to the surface microhardness (SMH) test and randomly divided in 12 experimental and one placebo groups. The blocks were submitted to pH cycling for 7 days, with daily applications once/day of 0.05% NaF and 0.1% NaF and twice/day of 0.02% NaF solutions. Four different pH: 4.0, 5.0, 6.0 and 7.0 were used. Next, SMH test was again used to determine the surface microhardness percentage change (%SMH). Data obtained for %SMH were homogeneous and passed through variance analyses and Tukey's test (5%) as far as fluoride concentrations and pH. Results: The results showed that pH influenced %SMH in 0.02% NaF and 0.05% NaF solutions with pH 4.0, which had less mineral loss compared to pH 7.0 (p<0.05). The 0.02% NaF - pH 4.0, and 0.05% NaF – pH 7.0 groups showed similar results (p>0.05). A dose-response relationship was observed among the tested solutions, with better anticariogenic effect for the 0.1% NaF solution. Conclusion: The results suggest that the addition of citric acid to acidulate mouth rinses reduce mineral loss.

Effect of trimetaphosphate and fluoride association on hydroxyapatite dissolution and precipitation in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento e caracterização de dispositivos eletroluminescentes contendo uma blenda polimérica condutora e Zn2SiO4:Mn

Despite the great development of organic and polymeric electroluminescent materials, the large scale commercial application of devices made with these materials seems conditioned to specific cases, mainly due to the high cost and the low durability, in compared to conventional technologies. In this study was produced electroluminescent devices by a process simple, drop casting. Were produced electroluminescent films containing Zn2SiO4:Mn immersed in a conductive polymer blend with different thicknesses. The morphological characteristics of these films were studied by scanning electronic microscopy. These films were used in the manufacture of electroluminescent devices, in which the light emission properties of the developed material were evaluated. The blend was composed of the conductive polymer Poly(o-methoxyaniline), doped with p-toluene sulfonic acid, and an insulating polymer, Poly(vinylidene fluoride) and its copolymer Poly(vinylidene fluoride-cotrifluoroethylene). To this blend was added Zn2SiO4:Mn, thereby forming the composite. A first set of devices was obtained using composites with different weight fraction of polymeric and inorganic phases, which were deposited by drop casting over ITO substrates. Upper electrodes of aluminum were deposited by thermal evaporation. The resulting device architecture was a sandwich type structure ITO/ composite/ Al. A second set of devices was obtained as self-sustaining films using the best composite composition obtained for the device of the first set. ITO electrodes were deposited by RF-Sputtering, in both faces of these films. The AC electrical characterization of the devices was made with impedance spectroscopy measurements, and the DC electrical characterization was performed using a source/ meter unit Keithley 2410. The devices light emission was measured using a photodiode coupled to a digital electrometer, Keithley 6517A. The devices electrooptical characterization showed that the...

Corrosion resistance of Ni-Cr alloys in different mouthwashes

Several alloys have been used for prosthodontics restorations in the last years. These alloys have a number of metals that include gold, palladium, silver, nickel, cobalt, chromium and titanium and they are used in oral cavity undergo several corrosion. Corrosion can lead to poor esthetics, compromise of physical properties, or increased biological irritation. The objective of this study was evaluated corrosion resistance of two alloys Ni-Cr and Ni-Cr-Ti in three types of mouthwashes with different active ingredients: 0.5g/l cetylpyridinium chloride + 0.05% sodium fluoride, 0.05% sodium fluoride + 0.03% triclosan (with fluor) and 0.12% chlorohexidine digluconate. The potentiodynamic curves were performed by means of an EG&G PAR 283 potentiostat/galvanostat. The counter electrode was a platinum wire and reference electrode was an Ag/AgCl, KCl saturated. Before each experiment, working electrodes were mechanically polished with 600 and 1200 grade papers, rinsed with distilled water and dried in air. All experiments were carried out at 37.0oC in conventional three-compartment double wall glass cell containing mouthwashes. The microstructures of two alloys were observed in optical microscopy. Analysis of curves showed that Ni-Cr alloy was less reactive in the presence of 0.12% chlorohexidine digluconate while Ni-Cr-Ti alloy was more sensitive for others two types of mouthwashes (0.5g/l cetylpyridinium chloride + 0.05% sodium fluoride  and 0.05% sodium fluoride + 0.03% triclosan). This occurred probably due presence of titanium in this alloy. Microstructural analysis reveals the presence of dendritic and eutectic microstructures for NiCr and Ni-Cr-Ti, respectively.

Perceptions of educators and students about using fluoridated mouthwashes

Purpose: The objective of this study was to assess the perceptions and opinions of public school teachers and students in the city of Araçatuba, SP, Brazil, on the importance of using fluoridated mouthwashes, the difficulties of the method and the procedure in general. Methods: Students from grades 5 through 8 in schools with and without dental services were asked about their opinion on the use of fluoridated mouthwashes. The educators answered questions about the importance of preventive methods in oral health and the difficulties in performing those methods at school. Data were collected using a faces scale, a categorization method, and a Likert scale with five levels of responses to check the level of agreement with the questions. Results: The sample consisted of 264 (40.3%) teachers and 5,788 (73.6%) students. A total of 254 (96.2%) and 72 (27.3%) teachers responded favorably to the first and second questions, respectively. A total of 1,128 (19.5%) students had negative feelings about the fluoridated mouthwash. Conclusion: The majority of the teachers supported the use of fluoridated mouthwashes; however, a large number of teachers believed that the practice disrupts the class routine. Most of the students had a positive opinion about the use of fluoridated mouthwash, although they highlighted some negative aspects, which were overcome by the benefits that the method provides.

Fluoretação das águas de abastecimento público no município de Araçatuba/SP

Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP)

Caries formation around restorative composite and glass ionomer cement

This in vitro study evaluated the demineralization around restorations class V made on the buccal and lingual surfaces of teeth when using different restorative materials. Thirty extracted teeth were randomly divided into 3 groups (n=10) according to the restorative material: Group I - Fuji II LC (GC America Inc., Alsip, Illinois, USA), Group II - Tetric (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Group III - Chelon Fil (3M/ESPE., Seefeld, Germany). The teeth were submitted to a pH-cycling model associated to a thermocycling model. Sections were made and the specimens were analyzed under a polarized light microscopy as for the presence of demineralization. Measurements were performed and the results were subjected to statistical analysis using Anova and Tukey´s Test (α=0.05). Mean values of demineralization depth (µm) according to each positions showed that the demineralization was significantly reduced when Chelon Fil (Group III) was used for all depths, when compared to fluoridated resin materials. Also, it was verified that non-fluoridated resin material, composite resin Tetric, had the lowest inhibitory effect on the development of demineralization.

Osteoporose: considerações sobre terapêuticas atuais e metabolismo ósseo

O processo de remodelação óssea é regulado por fatores sistêmicos e locais. Estrógeno é o hormônio mais importante na manutenção do turnover ósseo normal, cuja deficiência leva a alterações na remodelação óssea com reabsorção excedendo a formação, como observado em mulheres pós-menopausadas. O tratamento da osteoporose está relacionado com a descoberta de fármacos alternativo à terapia hormonal estrogênica compensando as desvantagens dessa terapêutica. O Raloxifeno (RLX) mimetiza os efeitos benéficos do estrógeno sem estimular tecidos como mama e endométrio. O Fluoreto de sódio (NaF) apresenta-se como agente eficaz no combate às fraturas, conseqüentes da osteoporose.

Efeito da incorporação do trimetafosfato de sódio microparticulado e nanoparticulado ao cimento de ionômero de vidro nas propriedades físico-mecânicas e na desmineralização do esmalte

Pós-graduação em Ciência Odontólogica - FOA

Estudo comparativo das características bioquímicas funcionais e especificidade catalítica de aspartil, cisteíno e serino peptidases fúngicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da adição de nanopartículas de hexametafosfato de sódio em dentifrícios fluoretados sobre a desmineralização dentária: estudo in vitro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)