Large bone defects present a common clinical problem where autologous bone grafting is the current gold standard. Autologous bone grafts harvested by the Reamer-Irrigator-Aspirator® (RIA) technique are considered advantageous in terms of larger quantities of graft material and yielding two fractions – a solid graft usually used for the transplantation and a liquid fraction often referred to as a waste material. This highly translational project aims to address the regenerative potential of RIA liquid fraction through in vitro studies of its secretory and cellular content as well as by testing pre-conditioning strategies to improve RIA grafts regenerative potential. Also, the project will provide evidence for the new application possibility of bone substitute material PerOssal® (Osartis GmbH) in combination with RIA-graft material. In vitro experiments will be translated into preclinical and clinical trials in Serbia to optimize currently available therapies. In parallel, proof-of-concept experiments with 3D printing materials will be accomplished with the industrial partner from Serbia 3D Republika d.o.o.