Reactivity of Titanium Dental Implant Surfaces in Simulated Body Fluid

Osseointegration of titanium (Ti) implants in bone is crucial for dental implant treatment. Bacterial challenge possibly leading to peri-implantitis threatens long-term success. For the improvement of osseointegration, an understanding of materials and tissue intervention is needed. This in vitro study analyzed changes of different implant surfaces exposed to simulated body fluid (SBF). Implants were analyzed by scanning electron microscopy/X-ray photoelectron spectroscopy. Supernatants (SNs) were assessed using inductively coupled plasma-mass spectrometry (ICP-MS). Additional calcium (Ca) and phosphate (P) crystals developed (Hank's buffered salt solution (HBSS)) on implants with layered surfaces. ICP of SN demonstrated a decreased Ca/P ratio. After incubation with human serum (HS), layers appeared flattened containing <1% Ca/P. The etched/machined implants showed the formation of a surface transformation layer or coating consisting of crystalline Ca/P precipitations and a decrease in the Ca/P ratio in the supernatant. Incubation in HS induced noncrystalline coverage, and increased Ti/Ca/P was detected in supernatants. HBSS induced crystals on surfaces of modified implants and crystalline covers on nonmodified implants containing Ca/P. The serum did not show the development of HA-like structures but showed dissolving effects. Titanium surfaces show completely altered behavior when incubated in serum-containing SBF.