Abstract
The authors have observed experimentally in pulp tissues of lased rat teeth the interesting phenomena that the secondary dentin formation growes reactively to fill the whole pulp cavity of the tooth within a few months after exposure to Ar laser or Nd-YAG laser. They have succeeded in producing similar changes in pulp tissues of rat teeth to that with Ar laser or Nd-YAG laser by using an Ar -dye laser with an extreamely low thermal effect after giving the rats HpD premedication. Recently in the case of human teeth exposed to the lasers similar changes to these experimental results in rat teeth have also been observed. These results will hopefully suggest the possibility of an epoch-making dentistry in biological endodontic therapy and biological root canal filling in the near future.
