The development of optimally performing biomaterials mimicking the natural physiological processes underlying bone repair is essential for non-healing large bone lesions. We sought to develop scaffolds that fill the lesions and improve bone healing. We tested three scaffolds comprised of varying percentages of lactide (LA), caprolactone (CL), and methacrylate produced by two-photon photopolymerization; LCM 3 (8:2; 85%), 4 (9:1; 90%), and 6 (9:1; 40%). We hypothesized that the quantity of specific polymer components may differentially impact bone regeneration. We first tested mouse calvarial-derived osteoblasts (OBs) in MTT and alkaline phosphatase assays as well as with alizarin red staining. We observed that LCM 3 and 4, but not LCM 6 induced mouse and human OBs to attach, proliferate, and produce mineralized matrix compared to negative controls. Secondly, we analyzed osteoclast (OC) development using co-culture-derived OCs and human CD14+OCs derived from blood. We observed that mouse and human OCs differentiated on LCM 3 and 4, but not on LCM 6, when compared to tissue culture plastic controls. Thirdly, we used a calvarial defect model in 3-month-old BALB/c mice to test scaffold integration. We found that implanted LCM 3 scaffolds induced a significant increase in bone regeneration in the defect compared to Vitoss and negative controls, as observed with quantum FX μCT. Remarkably, LCM 4 and 6 lacked osteoinductive ability. Taken together, these results indicate that a methacrylation degree of >50% seems to be a prerequisite for cellular attachment and that a higher content of CL promotes ossification and bone regeneration. surface.
17 May 2014 - 20 May 2014