Comparison of Hydrophilic Properties of Titanium and Zirconia Dental Implants' Surfaces

One of the key factors influencing osseointegration is the hydrophilicity of the surface of dental implants; high hydrophilicity is more advantageous than low hydrophilicity. This study aimed to compare the hydrophilic properties of titanium and zirconia implants from different manufacturers. An in vitro analysis was conducted on 15 implants-13 titanium and 2 zirconia-each featuring distinct compositions and surface treatments. Their hydrophilicity was assessed using the contact angle method, where a drop of saline solution was pipetted onto the apical part of the implant. For each implant, 30 contact angle measurements were taken at three different surface wetting time intervals. The contact angle is defined as the internal angle between the tangent to the surface of the liquid and the surface at the point of tangency; a smaller angle means a higher hydrophilicity. The results show that titanium implants from BTI UniCa, Nobel TiUltra, and Straumann Roxolid SLActive-which are classified as premium implants-exhibited the highest hydrophilicity. In contrast, zirconia implants demonstrated significantly lower hydrophilicity. Within this group, the Nobel Pearl implant exhibited smaller contact angles than the Bredent WhiteSKY implant. Our findings confirm that high-quality titanium implants show superior hydrophilicity, potentially improving clinical outcomes by accelerating healing and facilitating immediate loading protocols, but this could only be proven with an in vivo animal study. Conversely, the relatively lower hydrophilicity of zirconia implants highlights the need for continued advancements in zirconia composition and surface modification to optimize their osseointegration potential.