Development and characterisation of strontium-doped sol-gel coatings to optimise the initial bone regeneration processes

Abstract

Strontium plays an important role in bone regeneration; it promotes the differentiation and maturation of osteoblasts and inhibits the activity of osteoclasts. Our principal objective in this study was to formulate new organic-inorganic hybrid sol-gel coatings applied to titanium discs. These coatings were functionalised with different amounts of SrCl2 and examined using in vitro tests and proteomics. The chemical and morphological characteristics of obtained coatings were scrutinised. The in vitro evaluation using the MC3T3-E1 osteoblasts and RAW264.7 macrophages showed the osteogenic and anti-inflammatory effects of strontium doping. The proteomic assay identified 111 different proteins adhering to the coatings. Six of these proteins reduced their adhesion affinity as a result of Sr-doping, whereas 40 showed increased affinity. Moreover, the proteomic analysis revealed osteogenic and anti-inflammatory properties of these biomaterials. The analysis also showed increased adhesion of proteins related to the coagulation system. We can conclude that proteomic methods are invaluable in developing new biomaterials and represent an important tool for predicting the biocompatibility of dental implants.