PURPOSE: The purpose of this in vitro study was to analyze the toxicity of acrylate-based restorative composite resins filled with hydroxyapatite and a silica/hydroxyapatite combination.
MATERIAL AND METHODS: Five different restorative materials based on bisphenol A-glycidyl methacrylate (bis-GMA) and tri-ethylene glycol dimethacrylate (TEGDMA) were developed: unfilled (H0), hydroxyapatite-filled (H30, H50), and silica/hydroxyapatite-filled (SH30, SH50) composite resins. These were tested for in vitro cytotoxicity by using human bone marrow mesenchymal stromal cells. Surface morphology, elemental composition, and functional groups were determined by scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDX), and Fourier-transformed infrared spectroscopy (FTIR). The spectra normalization, baseline corrections, and peak integration were carried out by OPUS v4.0 software.
RESULTS: Both in vitro cytotoxicity results and SEM analysis indicated that the composite resins developed were nontoxic and supported cell adherence. Elemental analysis with EDX revealed the presence of carbon, oxygen, calcium, silicon, and gold, while the presence of methacrylate, hydroxyl, and methylene functional groups was confirmed through FTIR analysis.
CONCLUSIONS: The characterization and compatibility studies showed that these hydroxyapatite-filled and silica/hydroxyapatite-filled bis-GMA/TEGDMA-based restorative composite resins are nontoxic to human bone marrow mesenchymal stromal cells and show a favorable biologic response, making them potential biomaterials.
METHODS: We systematically searched Pubmed for population-based studies of chronic kidney disease (CKD) and ESKD epidemiology and management. Population-level data from 23 pre-designated nations were eligible for inclusion if they pertained to people receiving dialysis or kidney transplant for ESKD. When available, government websites were utilized to identify and extract data from relevant kidney registries . Measures gathered included those related to the prevalence and mortality of ESKD; the availability of nephrologists; per capita healthcare expenditures; and use of erythropoietin stimulating agents (ESAs).
RESULTS: We obtained data from the United States (US), 7 nations in Eastern Europe, 4 each in Western Europe, Latin America, and Africa, and 3 in Asia. Documented prevalence of ESKD per million population varied from a high of 3,600 (Malaysia) to a low of 67 (Senegal). Annual mortality associated with ESKD varied from 31% (Ethiopia and Senegal) to 10% (UK). Nephrologist availability per million population varied from 40 (Japan) to <1 (South Africa) and was associated with per capita healthcare expenditures.
CONCLUSIONS: The delivery of kidney care related to ESKD varies widely among countries. Higher per capita healthcare spending is associated with increased delivery of kidney care. However, in part because documentation of kidney disease varies widely, it is difficult to determine how outcomes related to ESKD may vary across nations.