Biomechanical testing of bioactive bone cements - a comparison of the impact of modifiers: antibiotics and nanometals

Apart from its bone filler and fracture stabilizing function, bone cement can be used as a carrier of bioactive substances, and such modified bone cement can protect the implant against microorganisms, treat local infections and combat bacteria introduced during the surgical procedure. In this paper, the effects of modifying antibiotics and nanosilver on the biomechanical properties of bone cement were examined. The following tests were carried out: curing time, wettability, microhardness, porosity, microstructure and mechanical tests. Additionally, preliminary tests on bactericidal properties in the form of bacterial growth inhibition zones were conducted. No negative impact of bioactive modifications on cement properties was observed, except for bending strength in bone cement with antibiotics. Unmodified bone cement and nanosilver-loaded cement fulfilled all of the requirements specified in the standards and assumptions regarding their biofunctionality. Antibiotic-loaded cement provided a greater range of bioactivity. Attention should be paid to the potential effects of nanosilver as regards the lack of bacterial resistance, prevention and destruction of biofilm structure and length of bioactivity. Bone cement containing nanometals can serve as an alternative to the bioactive bone cements that are currently in use.