Acute Inflammatory Response to Laser‐Induced Micro‐ and Nano‐Sized Titanium Surface Features

Abstract

The inflammatory process induced by implant surfaces is an important component of the tissue response, where limited knowledge is available regarding the role of surface topography. With laser ablation, a combined micro- and nanoscale surface modification could be created, which have been shown to enhance bone growth and biomechanical stability in vivo. The aim of this article was to evaluate the early in vivo inflammatory response to laser-modified titanium disks, with machined titanium disks and sham operation sites serving as controls. Circular disks were installed in a subcutaneous rat model for 24 and 72 hours, where the cell number, cell types, and cytokine levels were evaluated. The results revealed that significantly fewer inflammatory cells (mononuclear and polymorphonuclear) were attracted to the sites with the laser-modified implants compared with the machined titanium implants. Similar concentrations of pro-inflammatory cytokines (TNF-a and MCP-1), together with slightly higher cell viability, were observed around the laser-modified surface compared with the machined surface. The results in the present study suggest that the combination of surface micro and nano features of the laser-treated surface contributes to the downregulation of early inflammatory events.