Removable partial dentures (RPD) demand specific hygienic cleaning and the combination of brushing with immersion in chemical solutions has been the most recommended method for control of biofilm. However, the effect of the cleansers on metallic components has not been widely investigated. This study evaluated the effect of different cleansers on the surface of RPD. Five disc specimens (12 mm x 3 mm metallic disc centered in a 38 x 18 x 4 mm mould filled with resin) were obtained for each experimental situation: 6 solutions [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) control] and 2 Co-Cr alloys [DeguDent (DD) and VeraPDI (VPDI)] were used for each experimental situation. A 180-day immersion was simulated and the measurements of roughness (Ra, µm) of metal and resin were analyzed using 2-way ANOVA and Tukey's test. The surface changes and tarnishes were examined with a scanning electronic microscopy (SEM). In addition, energy dispersive x-ray spectrometry (EDS) analysis was carried out at representative areas. Visually, NaOCl and MI specimens presented surface tarnishes. The roughness of materials was not affected by the solutions (p>0.05). SEM images showed that NaOCl and MI provided surface changes. EDS analysis revealed the presence of oxygen for specimens in contact with both MI and NaOCl solutions, which might suggest that the two solutions promoted the oxidation of the surfaces, thus leading to spot corrosion. Within the limitations of this study, it may be concluded that the NaOCl and MI may not be suitable for cleaning of RPD.

ObjectiveRemovable partial dentures (RPD) require different hygiene care, and association of brushing and chemical cleansing is the most recommended to control biofilm formation. However, the effect of cleansers has not been evaluated in RPD metallic components. The aim of this study was to evaluate in vitro the effect of different denture cleansers on the weight and ion release of RPD. Material and MethodsFive specimens (12x3 mm metallic disc positioned in a 38x18x4 mm mould filled with resin), 7 cleanser agents [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) (control)] and 2 cobalt-chromium alloys [DeguDent (DD), and VeraPDI (VPDI)] were used for each experimental situation. One hundred and eighty immersions were performed and the weight was analyzed with a high precision analytic balance. Data were recorded before and after the immersions. The ion release was analyzed using mass spectrometry with inductively coupled plasma. Data were analyzed by two-way ANOVA and Tukey HSD post hoc test at 5% significance level. ResultsStatistical analysis showed that CT and MI had higher values of weight loss with higher change in VPDI alloy compared to DD. The solutions that caused more ion release were NaOCl and MI. ConclusionsIt may be concluded that 0.05% NaOCl and Medical Interporous tablets are not suitable as auxiliary chemical solutions for RPD care.

Natural rubber latex (NRL) from Hevea brasiliensis is a colloidal system composed of cis-1,4-polyisoprene. Its applications have grown due its angiogenic and wound healing activity. NRL has been used in guided bone regeneration as barrier, enhancing bone formation. However, there has been no study reported so far which shows its in vitro biocompatibility with osteoblasts. Thus, the aim of this work was to apply thermally induced phase separation under several temperatures to induce porosity in NRL; and test its mechanical properties, cytotoxicity, cell adhesion, and mineralization with MC3T3-E1. Only biomembranes submitted at 220 and 210 8C presented porosity. Fourier transform infrared spectroscopy showed no change in cis-1,4-isoprene spectra. Biomembranes were elastic (Young's modulus < 1 MPa). According to ISO10993-5, NRL showed no cytotoxicity. Cells adhered on the NRL and produced mineral matrix as analyzed by scanning electron microscopy-energy-dispersive spectrometry, von kossa, and Fourier transform infrared spectroscopy. Cells on NRL presented higher alkaline phosphatase activity, however, mineralization showed no difference by alizarin red S dye extraction.

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Luminescent zinc-based hybrid inorganic-organic films with rare-earth (RE) complexes have been prepared using a non-alkoxide sol-gel process. The films were fabricated by the dip-coating method starting from zinc acetate dihydrate, rare earth chloride, lactic acid as hydrolytic catalyst, and anhydrous ethanol. The beta-diketones thenoylltrifluoroacetone (Httfa) and dibenzoylmethane (Hdbm) were used as ligands to Eu(3+) and Tb(3+), respectively. After deposition of the first layer, the films were fired at temperatures between 50 and 300 degrees C, in air. Photophysical properties such as excitation, emission and emission, lifetimes were determined for the films obtained in different conditions. Eu(3+)/ttfa and Tb(3+)/dbm films fired at 300 and 250 degrees C, respectively, are still transparent and gave rise to intense emission when excited through the ligand (antenna effect).

O mogno africano (Khaya ivorensis A. Chev.) é mais uma espécie florestal que vem se destacando em cultivos comerciais no Brasil. No entanto, são escassas as informações sobre a necessidade de correção da acidez do solo e da nutrição das plantas. O objetivo deste estudo foi avaliar a efeito da calagem e da adubação fosfatada nos atributos químicos do solo, no crescimento inicial e na nutrição das plantas. O delineamento experimental foi inteiramente casualizado, com seis repetições, no arranjo fatorial 2 x 5. Os tratamentos foram dois níveis de calagem (sem e com) e cinco doses de fósforo (0, 10, 20, 30 e 40 mg dm-3 de P). As mudas, com 16,5 cm de altura, foram plantadas em vasos de 6,0 L, preenchidos com solo seco ao ar e peneirado em malha de 4,0 mm. Em intervalos de 60 dias, foi avaliada a altura e o diâmetro do colo das plantas do mogno africano. Aos 240 dias do plantio, foi quantificado os atributos químicos do solo, a massa seca e as concentrações de nutrientes das folhas, caule e raízes. A calagem em solo com saturação de bases de 38,5% não aumentou o crescimento das plantas, mas contribuiu para a redução da acidez, aumento da concentração de Ca e Mg no solo e nas folhas. A adubação fosfatada aumentou a disponibilidade de P no solo e contribuiu para o maior crescimento das plantas de mogno africano.