Polymethylmethacrylate (PMMA)-based cements are used for bone reparation due to their biocompatibility, suitable mechanical properties, and mouldability. However, these materials suffer from high exothermic polymerization and poor bioactivity, which can cause the formation of fibrous tissue around the implant and aseptic loosening. Herein, we tackled these problems by adding Sr 2+ -substituted hydroxyapatite nanoparticles (NPs) and a porogenic compound to the formulations, thus creating a microenvironment suitable for the proliferation of osteoblasts. The NPs resembled the structure of the bone's apatite and enabled the controlled release of Sr 2+ . Trends in the X-ray patterns and infrared spectra confirmed that Sr 2+ replaced Ca 2+ in the whole composition range of the NPs. The inclusion of an effervescent additive reduced the polymerization temperature and lead to the formation of highly porous cement exhibiting mechanical properties comparable to the trabecular bone. The formation of an opened and interconnected matrix allowed osteoblasts to penetrate the cement structure. Most importantly, the gas formation confined the NPs at the surface of the pores, guaranteeing the controlled delivery of Sr 2+ within a concentration sufficient to maintain osteoblast viability. Additionally, the cement was able to form apatite when immersed into simulated body fluids, further increasing its bioactivity.Therefore, we offer a formulation of PMMA cement with improved in vitro performance supported by enhanced bioactivity, increased osteoblast viability and deposition of mineralized matrix assigned to the loading with Sr 2+ -substituted hydroxyapatite NPs and the creation of an interconnected porous structure. Altogether, our results hold promise for enhanced bone reparation guided by PMMA cements.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.