Biofilm accumulation on additive manufactured Ti-6Al-4V alloy surfaces.

Purpose: This study investigated whether additive manufactured (AM) surfaces inhibit accumulation of bacterial biofilm on the surfaces of Ti-6Al-4V alloy dental implants. Bacterial biofilms are thought to cause peri-implant disease, which develops in mucosa surrounding titanium (Ti) and Ti alloy dental implants and can lead to bone loss and implant failure.

Methods: Accumulation of a Streptococcus mutans (ATCC 25175) biofilm on Ti-6Al-4V alloy was compared in relation to fabrication method, ie, AM using electron beam melting (EBM) or laser beam melting (LBM). Conventional lost-wax casting was used as positive control, and Teflon was used as negative control. Biofilm accumulation on the alloys and negative control (each n = 10) was conducted at 37°C under anaerobic conditions. After 4 h, the number of metabolically active S. mutans bacteria adhering to the alloy was determined with a bioluminescence assay.

Results: The quantitative roughness values of the specimens, before exposure to bacteria, ranked EBM > LBM > cast > Teflon.

Conclusion: The amount of biofilm accumulation on the investigated AM metals and cast metal controls did not significantly differ.