Ceramic materials mimic the mineral composition of native bone and feature osteoconductive properties; they are therefore used to regenerate bone tissue. Much research focuses on increasing the porosity and pore interconnectivity of ceramic scaffolds to increase osteoconductivity, cell migration and cell-cell interaction. We aimed to fabricate biocompatible 3D-scaffolds featuring macro- and microporous calcium phosphates with high pore interconnection. Nanoparticles of hydroxyapatite (HA) and calcium deficient hydroxyapatite (CDHA) were synthesized by wet chemical precipitation. Scaffolds were produced from them by the replication polymeric foam technique. Solid content and sintering temperature were varied. Nanoparticles and scaffolds were characterized regarding morphology, chemical and mineral composition, porosity and mechanical properties. Biocompatibility, cell attachment and distribution were evaluated in vitro with human adipose mesenchymal stem cells. Scaffolds with total porosity of 71%–87%, pores in the range of 280–550 µm and connectivity density up to 43 mm⁻³ were obtained. Smaller pore sizes were obtained at higher sintering temperature. High solid content resulted in a decrease of total porosity but increased interconnectivity. Scaffolds 50HA/50β-TCP featured superior interconnectivity and mechanical properties. They were bioactive and biocompatible. High HA solid content (40 wt.%) in the HA pure scaffolds was negative for cell viability and proliferation, while in the 50HA/50β-TCP composite scaffolds it resulted more biocompatible.

Introduction: Antibiotic-loaded bone cements of poly(methyl methacrylate) are considered as very useful biomaterials for the management of corporal deep osseous infections. However, the high prevalence of resistant germs and polymicrobial infections makes it necessary to search for new formulations of bone cements containing antibiotics for local antibacterial therapy. In this work, bone cements loaded with drugs with different mechanism of action were evaluated to determine its antibacterial effectiveness on Pseudomonas aeruginosa. Methodology: Poly(methyl methacrylate) cements loaded with 10 wt.% of Oleozon®, mixtures of Ciprofloxacin/Meropenem and Ciprofloxacin/Meropenem/Oleozon® were prepared. The in vitro drugs release in water was followed by UV-Vis spectroscopy, and their antibacterial activity against Pseudomonas aeruginosa was evaluated for 11 days using the microdilution method. Results: All the extracts demonstrated an inhibitory effect on the growth of the strain during the whole trial period. Extracts from cement with Oleozon® only presented a total antibacterial inhibitory effect during 20 hours for the extracts taken at day 1 while the extracts from the cements loaded with mixtures of Ciprofloxacin/Meropenem and Ciprofloxacin/Meropenem/Oleozon® showed complete inhibition of the growth of the microorganism, even at 11 days. At the end of the trial period, some of the drugs remained inside the matrices, indicating that they can be released for a longer time in treatments. Conclusions: The results indicated a positive antibacterial effect by the combined used of the two or the three drugs tested against the Gram-negative bacilli Pseudomonas aeruginosa, so these proposal may be a valid alternative to be considered by surgeons.

This work studied the eluting behavior of ciprofloxacin, meropenem, and ceftazidime (and their mixtures) with that of gentamicin from antibiotic-loaded bone cements (ALBCs). In vitro release was followed by UV–Vis for 30 days and a semiempirical eluting model that considers the processes of dissolution and diffusion were proposed: . The antimicrobial efficacy against Pseudomonas aeruginosa and Staphylococcus aureus of the prepared ALBCs was also evaluated. The results showed that the amount of antibiotic released increased when ciprofloxacin/meropenem or ciprofloxacin/ceftazidime was used and that their antibacterial inhibitory effect against microorganisms tested was improved as a consequence of the synergistic effect. GRAPHICAL ABSTRACT

This article presents the results of a study of the efficiency of silanation process of calcium phosphate glasses particles and its effect on the bioactivity behavior of glass- poly(methyl methacrylate) (PMMA) composites. Two different calcium phosphate glasses: 44.5CaO-44.5P₂O₅-11Na₂O (BV11) and 44.5CaO-44.5P₂O₅-6Na₂O-5TiO₂ (G5) were synthesized and treated with silane coupling agent. The glasses obtained were characterized by Microprobe and BET while the efficiency of silanation process was determined using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS) and Thermal Analysis (DTA and TG) techniques. The content of coupling agent chemically tightly bond to the silanated glasses ascended to 1.69 ± 0.02 wt % for BV11sil glass and 0.93 ± 0.01 wt % for G5sil glass. The in vitro bioactivity test carried out in Simulated Body Fluid (SBF) revealed certain bioactive performance with the use of both silanated glasses in a 30% (by weight) as filler of the PMMA composites because of a superficial deposition of an apatite-like layer with low content of CO₃²⁻ and HPO₄²⁻ in its structure after soaking for 30 days occurred. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 205–213, 2014.

Publicación centenaria de ámbito científico nacional e internacional que publica artículos sobre enfermedades y patologías que afectan al ser humano