IADR Abstract Archives
Laser-Sintered Titanium: Peri-Implantitis Pathogens Attachment and Tailored Antimicrobial Coating Development
Objectives: This study aimed to investigate surface properties of laser-sintered titanium alloy (Ti), their influence on the attachment of key pathogens associated with peri-implantitis (PI), and develop an antimicrobial coating to inhibit colonisation of key pathogens invoved in PI.
Methods: Physicochemical characterisation, including Fourier-transform infrared spectroscopy, surface profilometry, contact angle measurements and grain boundary visualisation, was performed on Ti discs. The PI-associated pathogens Fusobacterium nucleatum and Porphyromonas gingivalis were anaerobically cultured until mid-log phase. Ti discs were incubated for up to 2h in bacterial suspensions. Attachment and viability were quantified by microbiological culture counts and image analysis following fluorescence microscopy. A Design of Experiments program was used to model octadecylphosphonic acid (ODPA) grafting to Ti. Discs were incubated in ODPA-tetrahydrofuran solution (concentrations 0.5, 1, 5mM), then baked (incubation and baking times varied 1-5h). ODPA-Ti discs were subsequently incubated in triclosan (500µg/mL) loaded-liposomes (1mg/mL) suspension for 1h, 5h and 24h. Attachment of liposomes to ODPA-Ti was examined by scanning electron and fluorescent microscopy.
Results: The discs presented smooth and hydrophilic surfaces (Ra=0.056µm, contact angle=49degrees). Attachment of F. nucleatum and P. gingivalis to Ti showed important differences. At 2h, 42% F. nucleatum attached to Ti surfaces with 90% viability, while P. gingivalis showed 14% attachment and 98% viability. F. nucleatum formed patterns on the disc surfaces corresponding to the Ti grain boundaries produced during the laser-sintering process. ODPA grafting, heavily influenced by the three variables, was heterogeneously distributed on the surfaces forming monolayers and bilayers. Liposomes were successfully attached to ODPA-Ti and assessment of antimicrobial activity is ongoing.
Conclusions: This study demonstrates PI-associated pathogens can colonise implant biomaterial surfaces directly. The unique attachment pattern formation observed with F. nucleatum may indicate sensing capacity. A novel liposomal coating was successfully tethered to laser-sintered Ti. Such coatings may decrease bacterial load, potentially reducing the risk of PI.
Methods: Physicochemical characterisation, including Fourier-transform infrared spectroscopy, surface profilometry, contact angle measurements and grain boundary visualisation, was performed on Ti discs. The PI-associated pathogens Fusobacterium nucleatum and Porphyromonas gingivalis were anaerobically cultured until mid-log phase. Ti discs were incubated for up to 2h in bacterial suspensions. Attachment and viability were quantified by microbiological culture counts and image analysis following fluorescence microscopy. A Design of Experiments program was used to model octadecylphosphonic acid (ODPA) grafting to Ti. Discs were incubated in ODPA-tetrahydrofuran solution (concentrations 0.5, 1, 5mM), then baked (incubation and baking times varied 1-5h). ODPA-Ti discs were subsequently incubated in triclosan (500µg/mL) loaded-liposomes (1mg/mL) suspension for 1h, 5h and 24h. Attachment of liposomes to ODPA-Ti was examined by scanning electron and fluorescent microscopy.
Results: The discs presented smooth and hydrophilic surfaces (Ra=0.056µm, contact angle=49degrees). Attachment of F. nucleatum and P. gingivalis to Ti showed important differences. At 2h, 42% F. nucleatum attached to Ti surfaces with 90% viability, while P. gingivalis showed 14% attachment and 98% viability. F. nucleatum formed patterns on the disc surfaces corresponding to the Ti grain boundaries produced during the laser-sintering process. ODPA grafting, heavily influenced by the three variables, was heterogeneously distributed on the surfaces forming monolayers and bilayers. Liposomes were successfully attached to ODPA-Ti and assessment of antimicrobial activity is ongoing.
Conclusions: This study demonstrates PI-associated pathogens can colonise implant biomaterial surfaces directly. The unique attachment pattern formation observed with F. nucleatum may indicate sensing capacity. A novel liposomal coating was successfully tethered to laser-sintered Ti. Such coatings may decrease bacterial load, potentially reducing the risk of PI.