Adsorption of antibiotic TA to dental hard tissues

Antibiotic TA (TA) is a wide-spectrum, bactericidal antibiotic produced by Myxococcus xanthus strain TA. It was previously demonstrated that TA binds tightly to soft tissues while retaining its bactericidal activity in the bound form. The present study was undertaken to investigate TA adsorption to dental hard tissues. Slabs of dental tissues that had been cut from periodontally-involved extracted human teeth were treated with TA and then washed in saline with shaking (saline being replaced every 15 minutes). After 30, 60, and 120 minutes of washing, 45, 39, and 27% of the input TA activities were retained on the slabs, respectively. The tooth-bound TA was released slowly into the aqueous medium in active form. Similar experiments with beta-lactam antibiotics resulted in no significant adhesion to the slabs. The study demonstrates that TA binds tightly to dental tissues while retaining its bactericidal properties.