An RC Plasma Device for Sterilization of Root Canal of Teeth

The application of cold plasma in sterilization of a root canal of a tooth has recently attracted great attention. In this paper, a reliable and user-friendly plasma-jet device, which can generate plasma inside the root canal, is reported. The plasma can be touched by bare hands and can be directed manually by a user to place it into root canal for disinfection without causing any painful sensation. When He/O-2 (20%) is used as working gas, the rotational and vibrational temperatures of the plasma are about 300 K and 2700 K, respectively. The peak discharge current is about 10 mA. Preliminary inactivation experiment results show that it can efficiently kill Enterococcus faecalis, one of the main types of bacterium causing failure of root-canal treatment in several minutes.