Studio in vitro del processo di osteointegrazione mediante l'utilizzo di cellule staminali mesenchimali adulte

The aim of our study was to evaluate the properties of the laser-modified titanium surface, that are its skills of promoting a faster differentiation of human Mesenchymal Stem Cells (hMSCs) into osteoblasts and a more stable connection between differentiated cells and titanium comparing to the machined and the sand-blasted surfaces. Furthermore, we wanted to evaluate if titanium alone was a sufficient factor able to induce the differentiation towards the osteogenic lineage. Materials and methods: we harvested stem cells from an individual (after his consensus) and cultivated them into dishes with titanium disks presenting three different surfaces: machined (M), sand-blasted (S) and laser-modified (L). In the test group cells were cultivated in an osteogenic medium, while in the control group cells were seeded in a standard DMEM. Evaluations of the degree of differentiation were made with Alizarin coloration after 28, 38, 42, 49, 56 and 63 days of induction. Results: no signs of differentiation were evident in the control group, while in the test group there was a statistically significant differentiation evident since the fourth week. Laser-modified and sand-blasted surfaces showed similar values, greater than the machined surface. Discussion: the differentiation reached its peak on the sixth week for the laser-modified surface, and on the seventh week for the other two surfaces. After the peak, the differentiation had a slow decrease for the laser-modified surface and a rapid decrease for the other two. Conclusions: titanium alone can’t be considered a sufficient factor able to induce differentiation of human Mesenchymal Stem Cells into osteoblasts. Moreover, laser-modified induces a faster differentiation of stem cells and a more stable connection between osteoblasts and titanium.