Local Treatment of Osteomyelitis Using Sodium Calcium Silicophosphate Bioceramics for Antibiotic Delivery: In Vitro...

Osteomyelitis is a serious bone infection that causes inflammation and damage to the affected tissue. Conventional treatments include prolonged, high-dose systemic antibiotic therapy, and debridement surgery, which may ultimately lead to amputation. Recent studies have been conducted on local antibiotic delivery systems, using biomaterials as potential candidates. One of the main advantages of local treatment is that it reduces recovery time, minimizes the side effects associated with high doses of antibiotics used in systemic treatment, and allows for targeted treatment of the affected area. This study aimed to evaluate the controlled release of a mixture of vancomycin and gentamicin using a calcium sodium silicate phosphate bioceramic as a drug delivery vehicle. This bioceramic is a biocompatible, osteoconductive, osteoinductive, and angiogenic biomaterial. In vitro tests were conducted over 30 days to assess its antimicrobial activity against Staphylococcus aureus and Escherichia coli, using the Kirby-Bauer and microdilution methods. The bioceramic effectively delivered the antibiotics, and the release of vancomycin was more sustained than that of gentamicin, as demonstrated by the inhibition zones against S. aureus, with diameters exceeding 20 mm throughout the 30-day study period. In the case of E. coli, inhibition zones were observed until Day 15. Quantitative analysis confirmed a strong antibacterial effect against both microorganisms, achieving 100% growth inhibition during the evaluation period. In addition, four veterinary clinical cases and one control clinical case of osteomyelitis were treated with calcium-sodium silicophosphate beads impregnated with vancomycin/gentamicin. The patients recovered without complications 2 months after implantation. The combination of antimicrobial efficacy and biocompatibility properties supports the development of this technology for both veterinary and, potentially, human clinical applications.