The infections are caused by bacteria introduced to the bloodstream during dental work on sensitive, blood-rich gum tissue.
Bacteria can travel and infect the tissue surrounding prosthetic devices.
The study's results, published in an October issue of the Journal of Clinical Orthopedics and Related Research, suggest that antibiotics, taken one hour before extensive dental procedures and again eight hours afterward, might provide the best defense against infection. While many patients with infected total knee replacements can be treated successfully, the authors note, they are at increased risk for potential loss of function, loss of range of motion, mechanical problems and in rare cases, sepsis or death. The dental procedures associated with the infections included tooth extractions, root canals, periodontal surgeries and benign tumor removals. However, routine procedures may not require prophylaxis. In seven patients, the infections were closely linked to a dental procedure and emerged as long as eight years after their knee replacements.