Comparison of Titanium and PEEK Medical Plastic Implant Materials for Their Bacterial Biofilm Formation Properties

Abstract

This study investigated two of the most commonly used CAD-CAM materials for patient-specific reconstruction in craniomaxillofacial surgery. The aim of this study was to access the biofilm formation of <i>Staphylococcus aureus</i>, <i>Streptococcus mutans</i>, <i>Enterococcus faecalis</i>, and <i>Escherichia coli</i> on titanium and PEEK medical implant materials. Two titanium specimens (titanium grade 2 tooled with a Planmeca CAD-CAM milling device and titanium grade 5 tooled with a computer-aided design direct metal laser sintering device (CAD-DMLS)) and one PEEK specimen tooled with a Planmeca CAD-CAM milling device were studied. Bacterial adhesion on implants was evaluated in two groups (saliva-treated group and non-saliva-treated group) to imitate intraoral and extraoral surgical routes for implant placement. The PEEK medical implant material showed higher bacterial adhesion by <i>S. aureus</i>, <i>S. mutans</i>, and <i>E. coli</i> than titanium grade 2 and titanium grade 5, whereas <i>E. faecalis</i> showed higher adhesion to titanium as compared to PEEK. Saliva contamination of implants also effected bacterial attachment. Salivary coating enhanced biofilm formation by <i>S. aureus</i>, <i>S. mutans</i>, and <i>E. faecalis</i>. In conclusion, our findings imply that regardless of the implant material type or tooling techniques used, salivary coating plays a vital role in bacterial adhesion. In addition, the majority of the bacterial strains showed higher adhesion to PEEK than titanium.