Influence of extracellular matrix proteins in enhancing bacterial adhesion to titanium surfaces

Aim: To examine the influence of extracellular matrix (ECM) proteins in enhancing bacterial adhesion and biofilm formation on titanium surfaces. Materials and methods: The adherence of 21 bacterial isolates to prepolished 1 cm ² titanium samples was screened using fluorescence microscopy. Three isolates that exhibited "low" (Porphyromonas gingivalis R17870), "moderate" (Porphyromonas gingivalis 5335), and "extensive" (Prevotella denticola R9102) adherence to titanium were then examined for titanium adherence in the presence of the ECM proteins vitronectin, fibronectin, laminin, collagen type I, and collagen type IV. Results: Several ECM proteins had a considerable effect on increasing adherence of the bacteria to titanium compared to a control (no protein treatment). The most significant difference was seen with vitronectin for P. gingivalis 5335 (p < 0.001 at 4 h, 24-h incubation times) and P. gingivalis R17870 (p < 0.05 at 4 h, 24 h incubation times). For P. denticola R9102, vitronectin was not found to enhance adherence at 4 h, (p > 0.05), whilst collagen type I and fibronectin did result in significantly enhanced adherence (p < 0.05, 24 h). Conclusions: ECM matrix proteins promote adherence of potential periodontal pathogenic bacteria to titanium surfaces. Management of diseases such as peri-implantitis should focus on limitation of this bacterial adherence to reduce/eliminate biofilms.