Background Despite progress in surgical techniques, 1% to 2% of joint arthroplasties become complicated by infection. Coating implant surfaces with antimicrobial agents have been attempted to prevent initial bacterial adhesion to implants with varying success rates. We developed a silver ion-containing calcium phosphate-based ceramic nanopowder coating to provide antibacterial activity for orthopaedic implants. Questions/purposes We asked whether titanium prostheses coated with this nanopowder would show resistance to bacterial colonization as compared with uncoated prostheses. Methods We inserted titanium implants (uncoated [n = 9], hydroxyapatite-coated [n = 9], silver-coated [n = 9]) simulating knee prostheses into 27 rabbits' knees. Before implantation, 5 9 10 2 colony-forming units of Staphylococcus aureus were inoculated into the femoral canal. Radiology, microbiology, and histology findings were quantified at Week 6 to define the infection, microbiologically by increased rate of implant colonization/ positive cultures, histologically by leukocyte infiltration, necrosis, foreign-body granuloma, and devitalized bone, and radiographically by periosteal reaction, osteolysis, or sequestrum formation. Results Swab samples taken from medullary canals and implants revealed a lower proportion of positive culture in silver-coated implants (one of nine) than in uncoated (eight of nine) or hydroxyapatite-coated (five of nine) implants.

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In this study, the antibacterial, cytotoxic, and angiogenic activities of silver doped calcium phosphate-based inorganic powder (ABT or PAG) were systematically investigated. ABT powders containing varying silver content were fabricated using a wet chemical manufacturing method. Antibacterial efficiencies of the ABT powders were investigated using a standard test with indicator bacteria and yeast. The cytotoxic effects of ABT on three different fibroblast cells and human umbilical vein endothelial cells (HUVECs) were assessed using MTT assay. ABT powder exhibits concentration-related cytotoxicity characteristics. Apoptotic activity, attachment capability, and wound healing effects were examined on fibroblasts. The angiogenic activity of ABT was investigated by tube formation assay in HUVECs; 10 μg ml(-1) and 100 μg ml(-1) concentrations of the highest metal ion content of ABT did not disrupt the tube formation of HUVECs. All these tests showed that ABT does not compromise the survival of the cells and might impose regeneration ability to various cell types. These results indicate that silver doped calcium phosphate-based inorganic powder with an optimal silver content has good potential for developing new biomaterials for implant applications.

In this study, the investigation of the optical properties and microstructural development of matte glaze compositions prepared with the addition of seashells was aimed. The seashells obtained from Black Sea beaches of Samsun, Turkey were characterized using XRF, XRD, FTIR, TG‐DTA techniques, and heating microscope. The calcite‐aragonite polymorphic transition was provided by heat treatment of seashell powders at 700°C for 1 hour and then, aragonite‐based seashell powders were incorporated to matte glaze compositions up to 30 wt%. Firstly, four different types of fired body specimens (red clay, chamotte, white, and porcelain) were produced at 800ºC for 7 hour. Secondly, the prepared glazes were applied on surface of all fired bodies and then, all bodies were sintered at 1100ºC for 8 hour. Finally, coloring parameters and microstructural features of seashell added glazes were determined. The addition of seashells to glaze composition by 10 and 20 wt% resulted in higher transparency. The matte glaze was formed with increment of seashell content to 30 wt%. The more reduced fluidity of the glaze caused nonhomogenous matte appearance. As a result, it is possible to produce transparent glazes in eco‐friendly and cost‐effective way by addition of seashells into glaze composition in 20 wt%.

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In this study, the effect of seashell utilization as a replacement for calcite on the surface features and optical properties of white ceramic glazes was investigated. As received seashells collected from Black Sea beaches of Samsun, Turkey and purified seashells at 700°C for 1 h were used as calcite replacement by 15 wt.%. Seashell powders were incorporated to white glaze compositions which are applied on the surface of different fired clay bodies such as red clay, chamotte, white and porcelain by dipping technique. Next, the glazed green bodies were sintered at 1100ºC for 8 h. Following to TG-DTA, heating microscope, XRD and optical analysis, the obtained results exhibited that as received seashell powder (SP-1) was composed of calcite (CaCO3), whereas purified seashell powder (SP-2) comprised aragonite (CaCO3) and calcium oxide (CaO). The iron (hematite) content in red clay and the impurities in seashells composition caused specks and crawlings on the surface of glazed red clay bodies and of some glazes containing seashell, respectively. In generally, the higher CaO content in SP-2 enhanced gloss (60°) values, and whiteness values of most glazed surfaces were closed to each other. The color of chamotte bodies increased redness-greenness values. The variations in optical parameters were mainly associated with the difference in body compositions. SP-1 contained glaze, applied on porcelain body, was selected as optimal because that had 33 gloss value, high whiteness (87) and no surface defect. Therefore, the utilization of as received seashells by 15 wt.% as calcite replacement allows eco-friendly and cost-effective production of white ceramic glazes without any additional heat treatment.

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Çalışmanın amacı, seramik bünyeler üzerine uygulamak üzere şeffaf sırların bor türevi atığının katkılanması ile daha ekonomik ve çevreci bir yöntem ile üretimidir. Bor türevi atığı katkılı şeffaf seramik sırları üretilmiş ve bu sırlar üretilen seramik bünyeler üzerine fritleme yapılmadan doğrudan uygulanmıştır. Değişken pişirme sıcaklığı (950 ºC-1150 ºC) ve atık katkı oranına (0-15 %ağ.) bağlı olarak XRD ve spektrofotometre kullanılarak sırların faz gelişimleri ve optik özellikleri incelenmiştir. 950 ºC’de üretilen sırlarda görülen adacık kusuru ve iğne deliği yüzey hataları 1150 ºC’de tüm sırların yapısının tamamen amorflaşması ile giderilmiştir ve atık katkılı sırların parlaklık değerleri artmıştır. Düşük sıcaklıklarda atık miktarı ile artan diopsit fazı parlaklık (60º) değerlerinde azalmaya ve beyazlık (L*) değerlerinde artışa sebep olmuştur. Özetle, 1150 ºC’de pişirim yapıldığında %5 atık katkılı sırın parlaklık ve beyazlık değerleri (56,6 ve 87,7) katkısız sıra (49,4 ve 85,3) kıyasla daha yüksektir. Üretilen düşük maliyetli ve çevre dostu bor atığı katkılı sırlar sanatsal seramik çalışmalarında kullanılabilir.