. "They range from the plaque on teeth to the slime on streamside rocks to the sludge that clogs pipes.Most biofilms are harmless, but some have been linked to ailments such as urinary tract infections, gingivitis and infections around implanted devices like artificial joints and heart valves.In the world that I study, everybody's trying to kill the biofilm, said Goeres, a research professor in the" . . . .