In the past decades, titanium-based biomaterials have been broadly used in maxillofacial and periodontology surgery. The main aetiological agents related to complications in this procedures are Porphyromonas gingivalis, a Gram-negative anaerobic bacteria that is also responsible for the development of chronic gingivitis, and Streptococcus oralis, a Gram positive facultative anaerobic bacteria. In previous studies, we have demonstrated that the fluorine doping of titanium-based alloys reduces bacterial adherence. The aim of this study is to evaluate the bacterial adherence on fluorine-doped titanium (TiF) probes compared to chemical polishing titanium (Ti) probes. The P. gingivalis ATCC 33277 and S. oralis ATCC 9811 adherence study was performed by introducing each probe in a well of 6-well plate with 5 ml containing 106 colony forming units (CFU/ml) in sterile 0.9% NaCl and was incubated 37°C 5% CO2 for 90 minutes, in anaerobiosis in the case of P. gingivalis. After incubation, samples were stained with LIVE/DEAD BacLight Bacterial Viability Kit. Proportion of live and dead bacteria was calculated and studied by using ImageJ software. The experiments were performed in triplicate. The statistical data were analyzed by nonparametric Wilcoxon test with a level of statistical significance of 0.05. Our results showed a significant (p<0.0053) 14.41% decrease of the adherence of P. gingivalis on TiF and an increase of 30% of dead cells. For S. oralis we did not get significant results. In conclusion, TiF can be considered a promising approach to prevent and treat infections related to maxillofacial and periodontology surgery.
Prosthetic joint infections (PJI) occur infrequently, but they represent the most devastating complication with high morbidity and substantial cost. Staphylococcus aureus and coagulase-negative S. epidermidis are the most commonly infecting agents associated with PJI. Nowadays, Gram-negative species like Escherichia coli and Pseudomonas aeruginosa are gaining relevance. The use of TiO2 conical nanotubular doped with fluorine and phosphorous (FP-cNT) surfaces is an interesting approach to prevent surface bacterial colonization during surgery and favouring the osseointegration. Despite of there are serum markers related with PJI, to date there is described no biomaterial-related marker that allows detecting PJI. Here we describe the adherence and the bactericidal effect of FP-cNT and its capacity of marking the non-fermenting bacteria that have been in contact with it by Al. This metal is delivered by FP-cNT in non-toxic concentrations (between 25 and 29 ng/mL). F-P-cNT layers on Ti6Al4V alloy were produced as described previously by our group. Ti6Al4V chemical polishing (CP) samples without nanostructure were used as control and produced as described previously. S. aureus 15981, S. epidermidis ATCC 35984, E. coli ATCC 25922, and P. aeruginosa ATCC 27853 strains adherence study was performed using the protocol described by Kinnari et al. in 0.9% NaCl sterile saline with a 120 min incubation. After incubation, the samples were stained with LIVE/DEAD BacLight Bacterial Viability Kit. Proportion of live and dead bacteria was calculated and studied by using ImageJ software. The experiments were performed in triplicate. The aluminum concentration was estimated in the supernatant after incubation and in the 0.22 µm filtered supernatant by atomic absorption in graphite furnace. The statistical data were analyzed by nonparametric Kruskal-Walis test and by pairwise comparisons using the nonparametric unilateral Wilcoxon test with a level of statistical significance of p<0.05. The values are cited as medians. Our results show that the bacterial adherence of all tested species significantly decreased on FP-cNT compared to CP except P. aeruginosa ATCC 27853: 19.8% for S. aureus 15981, 45.3% for S. epidermidis ATCC 35984 and 8.1% for E. coli ATCC 25922. The bacterial viability decreased 2-fold for S. aureus 15981, and 5-fold for S. epidemidis ATCC 35984, but increased 95% for P. aeruginosa ATCC 27853 and there no was variation for E. coli ATCC 25922 on FP-cNT compared to CP. Only supernatant P. aeruginosa ATCC 27853 shows significant Al detection after 120 min incubation (p<0.05). In summary, F-P cNT is a promising biomaterial that besides favoring osseointegration and potential usefulness as drug carrier, present bactericidal, non-stick ability (at least for staphylococci and E. coli) and is able to mark P. aeruginosa with Al, which could be potentially monitored in serum and urine in patients with PJI.
Implant-related infection is one of the most devastating complications in orthopaedic surgery. Many surface and/or material modifications have been developed in order to minimise this problem; however, most of the We describe a method for the study of bacterial adherence in the presence of preosteoblastic cells. For this purpose we mixed different concentrations of bacterial cells from collection and clinical strains of staphylococci isolated from implant-related infections with preosteoblastic cells, and analysed the minimal concentration of bacteria able to colonise the surface of the material with image analysis.Objectives
Methods
Prosthetic joint infections (PJI) occur infrequently, but due to its increased clinical use represent the most devastating complication with high morbidity and substantial cost. Staphylococcus aureus and coagulase-negative staphylococci are the most common infecting agents associated with PJI. A possible therapeutic approach could be the local antibiotic by fluoride-TiO2 nanostructured anodic layers in order to prevent surface colonisation during the early moments after surgery. Here we describe the first results of this model using two common antibiotics. Fluoride-TiO2 nanostructured anodic layers on Ti6Al4V alloy were produced as described previously by Arenas et al (2013). Discs shaped pieces of Ti6Al4V alloy were loaded with a solution of 150 mg antibiotic (vancomycin or gentamicin)/20 ml sterile distilled water. Samples were immersed in this solution during 24 hours at room temperature with agitation, and then were dried during 48 hours at 20°C. Antibiotic release was studied by introducing both discs in sterile PBS and samples were taken at different times. Samples were then frozen at −80°C until HPLC measurements and biological activity tests using Bacillus subtilis ATCC 6051 (vancomycin) and Escherichia coli ATCC 25922 (gentamicin) were performed.Introduction
Methods
Description of an original in vitro protocol for assessing combined bacteria and cell competitive adherence on the surface of biomaterials of medical interest Biomaterial-related infections are a major clinical problem. The pathogenesis of this syndrome has been described as a competitive adherence between bacteria and human cells in the so-called “race for the surface” theory. The aim of this study is to develop an Summary Statement
Objectives
Biomaterial-related infections are an important complication in orthopaedic surgery [1], and A 18mm diameter rod of Ti–6Al–4V alloy ELI grade according to the standard ASTMF136-02 supplied by SURGIVAL was cut into 2 mm thick disk specimens, ground through successive grades of SiC paper to 1200 grade, degreased with a conventional detergent and rinsed in tap water followed by deionised water. The specimens were then chemically polished (CP). The disks were anodized only on one side by using a two electrode cell in a suitable electrolyte. TiO2 barrier layers, without fluoride (BL), were produced by anodizing in 1 M H2SO4 at 15 mA cm-2 to 90 V, reaching 200 nm of thickness. Fluoride barrier layers (FBL) were produced in an electrolyte containing 1 M NH4H2PO4 and 0.15 M NH4F, at constant voltage controlled at 20 V for 120 min at 20°C; the thickness of the layer is 140 nm. Laboratory biofilm-forming strains of INTRODUCTION
MATERIAL AND METHODS
