laser to help you say goodbye to dentist's chair

Anyone who has had a root canal done knows how painful the procedure can be.

But a dental condition that may require one to undergo root canal may no longer give patients sleepless nights as researchers have found that exposing cells on the inside of a tooth to weak laser light stimulates the growth of dentin - the substance that makes up much of a tooth's structure.

low-power light could trigger stem cells inside the body to regenerate tissue, the study said.

"Our treatment modality does not introduce anything new to the body, and lasers are routinely used in medicine and dentistry, so the barriers to clinical translation are low," said David Mooney, a professor at the Harvard School of Engineering and Applied Sciences (SEAS) in the US.

So far, experiments have been done on rats and mice but the researchers have tested the technique on human cells in culture, and it seems to work, said Priveen Arany, an assistant clinical investigator at the National Institutes of Health.

Researchers took rodents to the laboratory version of a dentist's office to drill holes in their molars, treat the tooth pulp that contains adult dental stem cells with low-dose laser treatments, applied temporary caps, and kept the animals comfortable and healthy.

After about 12 weeks, high-resolution x-ray imaging and microscopy confirmed that the laser treatments triggered the enhanced dentin formation.

The new work marks the first time that scientists have gotten to the nub of how low-level laser treatments work on a molecular level, and lays the foundation for controlled treatment protocols.

A root canal is necessary when too much of a tooth is infected or damaged, and there is not any way to prevent the problem from getting worse (other than removing the tooth entirely).

The findings appeared in the journal Science.