RESUMEN
Silica particles were obtained from rice husk to which layered double hydroxide particles were deposited (weight ratio 1 : 1). Fe2+-Al3+ layered double hydroxides (FeAl-LDH) were synthesized by co-precipitation with ratios Fe : Al of 3 : 1 in the presence of SiO2 particles from the rice husk. Characterization of the synthesized FeAl-LDH@SiO2 particles was performed by X-ray diffraction, Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy with EDS. Prepared FeAl-LDH@SiO2 particles were used as reinforcing agents in 1, 3 and 5 wt% quantity in poly (methyl) methacrylate matrix. The aim of this study was to examine whether FeAl-LDH@SiO2 particles affect the mechanical properties of polymer composite materials. The morphology of the composites was examined using a field emission scanning electron microscope. Microindentation, tensile and impact testing determined the mechanical properties of the obtained composites.
RESUMEN
OBJECTIVES: The purpose of this study was to evaluate efficacy of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACFP) containing pastes among individuals with Sjögren's syndrome (SS). MATERIALS AND METHODS: Thirty patients were randomised into three groups: CPP-ACP, CPP-ACFP, and 0.05 % NaF to be used two times a day during a 28-day experimental period. Saliva was analysed for flow rate, pH, buffering capacity and mineral concentrations. Dental plaque was examined for pH. Following the formation of artificial carious lesion, participants wore enamel slabs for an in situ remineralisation study. Remineralisation potential was examined using scanning electron microscope (SEM) and energy dispersive spectroscopic (EDS) technique. SE microphotographs were subsequently analysed for area, diameter, perimeter, roundness and the number of enamel defects and percentage of tooth surface affected by defects. RESULTS: At the end of the experimental period, a slight increase of salivary pH could have been observed. No differences in mineral composition of saliva were noted. The use of CPP-ACP and CPP-ACFP contributed to a significant rise of plaque pH. Image analysis revealed excessive reduction of defects' dimensions in the three experimental groups, and a decrease of the number of enamel defects in the CPP-ACP and CPP-ACFP groups. The EDS analysis did not show differences in Ca/P, Ca/O and P/O ratios in any of the treatment groups. CONCLUSION: CPP-ACP and CPP-ACFP hold promise as remineralising agents for patients with SS. CLINICAL RELEVANCE: Pastes containing CPP-ACP/CPP-ACFP show enhanced remineralisation potential compared with NaF mouthrinse in patients with SS.