Abstract:
In recent decades, due to some limitations from alumina (Al2O3) and zirconia (ZrO2), silicon nitride (Si3N4) has
been investigated as a novel bioceramic material, mainly in situations where a bone replacement is required.
Si3N4 ceramics and its derivative form, SiAlON, possess advantages in orthopedics due to their mechanical
properties and biologically acceptable chemistry, which accelerates bone repair. However, biological applica-
tions require additional properties, enabling stronger chemical bonding to the surrounding tissue for better
fixation and the prevention of bacteria biofilm formation. Therefore, two commercial Si3N4 and SiAlON ceramics
were investigated in this study and compared to each other according to their material properties (like wetting
angles and surface chemistry) and their antibacterial behaviors using E. coli. Results provided evidence of a 15%
reduction in E. coli colonization after just 24 h on Si3N4 compared to SiAlON which is impressive considering no
antibiotics were used. Further, a mechanism of action is provided. In this manner, this study provides evidence
that Si3N4 should be further studied for a wide range of antibacterial orthopedic, or other suitable biomaterial
applications.
