The potential of the three-dimensional printed titanium mesh implant for cranioplasty surgery applications: Biomechanical behaviors and surface properties.

The aim of the present study was to investigate the biomechanical behaviors of the pre-shaped titanium (PS-Ti) cranial mesh implants with different pore structures and thicknesses as well as the surface characteristics of the three-dimensional printed Ti (3DP-Ti) cranial mesh implant. The biomechanical behaviors of the PS-Ti cranial mesh implants with different pore structures (square, circular and triangular) and thicknesses (0.2, 0.6 and 1 mm) were simulated using finite element analysis. Surface properties of the 3DP-Ti cranial mesh implant were performed by means of scanning electron microscopy, X-ray diffraction and static contact angle goniometer. It was found that the stress distribution and peak Von Mises stress of the PS-Ti cranial mesh implants significantly decreased at the thickness of 1 mm. The PS-Ti mesh implant with the circular pore structure created a relatively lower Von Mises stress on the bone defect area as compared to the PS-Ti mesh implant with the triangular pore structure and square pore structure. Moreover, the spherical-like Ti particle structures were formed on the surface of the 3DP-Ti cranial mesh implant. The microstructure of the 3DP-Ti mesh implant was composed of α and rutile-TiO2 phases. For wettability evaluation, the 3DP-Ti cranial mesh implant possessed a good hydrophilicity surface. Therefore, the 3DP-Ti cranial mesh implant with the thickness of 1 mm and circular pore structure is a promising biomaterial for cranioplasty surgery applications.

The application of silver nano-particles on developing potential treatment for chronic rhinosinusitis: Antibacterial action and cytotoxicity effect on human nasal epithelial cell model.

Chronic rhinosinusitis (CRS) has raised attentions both in many countries due to its high relapsing rate and the resistance of certain treatments especially antibiotics application on both acute and chronic bacterial rhinosinusitis. The aim of this research is stressing on developing an effective alternative treatment for treating CRS and reducing the use of antibiotics to avoid further resistance forming. The antibacterial functions of silver nano-particles (AgNPs) are well known according to previous reports and studies. However, for developing a suitable treatment for further clinical application, a variety of AgNPs cell cytotoxicity experiments and AgNPs antibacterial properties experiments were examined in vitro in this study. For imitating the clinical condition of CRS, the human nasal epithelial cell line (RPMI2650) has chosen as experimental model. Moreover, Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) were selected for antibacterial function experiments. The analytical results demonstrated that 5ppm of AgNPs not only maintains >80% of cell activity to RPMI2650, but also possesses >80% of antibacterial function to S. aureus and 100% of antibacterial function to E. coli. Therefore, 5ppm of AgNPs might be considered as a promising antibacterial agent for treating CRS.