LAUSR

This study aimed to investigate whether strontium (Sr) ion delivery to the surface of microstructured titanium (Ti) oral implants drives favorable osteoblast functions of mesenchymal stem cells (MSCs) under a Porphyromonas gingivalis lipopolysaccharide (LPS)-stimulated inflammatory condition. The goal is to gain insight for future surface engineering of Ti implants with increased resistance to peri-implantitis and better bone recovery capacity from peri-implant bone destruction. The Sr ions were introduced into a clinically available sandblasted/acid-etched (SLA) Ti implant surface by wet chemical treatment. The results showed that Sr ion incorporation enhances the osteogenesis-related cell functions of bipotent ST2 stem cells in the microstructured SLA type implant surface. Early spreading and osteogenic differentiation (osteogenesis-related mRNA expression, ALP activity and osteocalcin protein secretion) were notably increased in Sr-incorporated SLA implant surface under 1 µg of P. gingivalis LPS stimulation. In addition, Sr ion modification increased early osteogenic differentiation (ALP mRNA expression and ALP activity) of ST2 cells, again under the more severe inflammatory condition induced by a high dose of LPS (10 µg/mL). These results indicate that surface chemistry modification using Sr ions provides microstructured Ti oral implants with greater resistance to the development and progression of inflammatory bone tissue destruction, and increased bone recovery capacity in the bacterial LPS-contaminated Ti oral implant surface by enhancing the early osteogenic differentiation of MSCs.