Inhibition of Staphylococcus aureus Growth on Agar Plates Using Bone Cement Beads Mixed with Gentamicin and Zinc Ions

Abstract

Chronic bone infection (chronic osteomyelitis) is a common condition that takes a long time to heal and has the potential to lead to disability. The use of bone cement mixed with antibiotics is one of the approved options for the treatment of bone infections because it allows drugs to be delivered directly to the infected area in high doses, helping to avoid side effects associated with intravenous drug administration. However, increasing antibiotics has become a concern, necessitating the search for alternative disinfectants that can be used either as replacements or unconjunction with currently used antibiotics

This study was conducted in a microbiology laboratory, Singburi Hospital The researcher cast bone cement pellets mixed with gentamicin and bone cement mixed with zinc ions to compare their effectiveness against Staphylococcus aureus using the agar diffusion method over a period for 7 days. The main outcome measure was the zone of inhibition of mold-made gentamicin-impregnated PMMA and mold-made zinc ion-impregnated PMMA.        

The experimental results showed that the zone of inhibition of bone cement cast pellets mixed with gentamicin is 15 mm wider than the standard for bacterial susceptibility, both g gentamicin-mixed. And zinc ions-mixed bone cast pellets were classified as a strong bactericidal agent. Comparative results for inhibiting the growth of S. aureus on agar plates revealed that the zone of inhibition of bone cement pellets mixed with gentamicin was significantly wider than that of bone cement pellets mixed with zinc ions (t = 11.17, p < 0.001). The efficacy of bone cement beads mixed with gentamicin was strong l, with an average inhibiting zone of 18.41 mm, while the zinc ion-mixed bone cement beads also showed strong efficacy, with a mean inhibition zone of 14.50 mm. The comparison confirmed that the zone of inhibition of gentamicin-mixed bone cement beads was significantly wider than that of zinc ion-mixed bone cement beads (p < 0.001).