Cell viability evaluation of human primary osteoblasts in mono-culture.

<p><b>A)</b> Metabolic activity of human primary osteoblasts (hOB) incubated for 2 and 7 days on Ti6Al4V, PALACOS^® R, and PALACOS^® R+G+V, and measured using the WST-1 assay. Values are given as percentage of the polystyrene control. PALACOS^® R+G+V displayed lower cell activity than the other materials on both days. (*) Denotes significance with respect to the polystyrene control at each time point, and (+) significance with respect to the same material on day 2 (n = 4, mean ± SEM). <b>B)</b> Live/dead staining of the hOB cultured in a monolayer on the test samples after 2 and 7 days of incubation. All images were taken at 40x magnification. Scale bars are 200 μm.</p

SEM images of different samples.

<p>Row 1: Test samples in medium. Rows 2 and 3: hOB mono-culture on test samples. Rows 4 and 5: <i>S</i>. <i>epidermidis</i> mono-culture on test samples. Rows 6 and 6: Co-culture of hOB and <i>S</i>. <i>epidermidis</i> on test samples. Images were taken at magnification 500x, 2000x or 2500x.</p

Evaluation of metabolic activity of biofilm-bound <i>S</i>. <i>epidermidis</i> in mono-culture.

<p><b>A)</b> Metabolic activity of biofilm-bound <i>S</i>. <i>epidermidis</i> incubated for 2 and 7 days on Ti6Al4V, PALACOS^® R, and PALACOS^® R+G+V, and measured using the WST-1 assay. Values are given as a percentage of the polystyrene control. PALACOS^® R+G+V displayed approximately 25% and 0% activity after 2 and 7 days respectively. (*) Denotes significance with respect to the polystyrene control at each time point, and (+) significance with respect to the same material on day 2 (n = 4, mean ± SEM). <b>B)</b> Live/dead staining of the biofilm-bound <i>S</i>. <i>epidermidis</i> on the test samples after 2 and 7 days of incubation. All images were made at 400x magnification. Scale bars are 20 μm.</p

Quantification of viable planktonic <i>S</i>. <i>epidermidis</i> by CFU counting.

<p>Viable planktonic <i>S</i>. <i>epidermidis</i> were quantified in the medium after 2 and 7 days of cultivation with and without hOB on the 4 test samples (polystyrene control, TI6Al4V, PALACOS^® R, PALACOS^® R+G+V). Qualitatively, we observed the same results as for biofilm-bound <i>S</i>. <i>epidermidis</i>, except for PALACOS^® R+G+V where viable cells remain after 2 days in both experiments and after 7 days in the co-culture. (*) Denotes significance with respect to the polystyrene control, and (#) significance with respect to the mono-culture (n = 4, mean ± SEM).</p

Quantification of viable biofilm-bound <i>S</i>. <i>epidermidis</i> by CFU counting.

<p><i>S</i>. <i>epidermidis</i> mono-culture and co-culture with hOB in the biofilm on the 4 test samples (polystyrene control, TI6Al4V, PALACOS^® R, PALACOS^® R+G+V) after 2 and 7 days. PALACOS^® R+G+V test samples showed minimal viable bacteria except in the co-culture after 2 days. (*) Denotes significance with respect to the polystyrene control, and (#) significance with respect to the mono-culture (n = 4, mean ± SEM).</p