Influence of the Phase Composition of Titanium Alloys on Cell Adhesion and Surface Colonization

The pivotal role of metal implants within the host's body following reconstructive surgery hinges primarily on the initial phase of the process: the adhesion of host cells to the implant's surface and the subsequent colonization by these cells. Notably, titanium alloys represent a significant class of materials used for crafting metal implants. This study, however, marks the first investigation into how the phase composition of titanium alloys, encompassing the volume fractions of the alpha, beta, and omega phases, influences cell adhesion to the implant's surface. Moreover, the research delves into the examination of induced hemolysis and cytotoxicity. To manipulate the phase composition of titanium alloys, various parameters were altered, including the chemical composition of titanium alloys with iron and niobium, annealing temperature, and high-pressure torsion parameters. By systematically adjusting these experimental parameters, we were able to discern the distinct impact of phase composition. As a result, the study unveiled that the colonization of the surfaces of the examined Ti-Nb and Ti-Fe alloys by human multipotent mesenchymal stromal cells exhibits an upward trend with the increasing proportion of the omega phase, concurrently accompanied by a decrease in the alpha and beta phases. These findings signify a new avenue for advancing Ti-based alloys for both permanent implants and temporary fixtures, capitalizing on the ability to regulate the volume fractions of the alpha, beta, and omega phases. Furthermore, the promising characteristics of the omega phase suggest the potential emergence of a third generation of biocompatible Ti alloys, the omega-based materials, following the first-generation alpha-Ti alloys and second-generation beta alloys.