There were 5 groups of rats in the study. Groups 2 through 5 were injured in a controlled operation. Groups 3 through 5 were given different dosage of laser therapy.
Group 1: No damage
Group 2: Damaged and then area treated with placebo
Group 3: Damaged and given non-optimal therapy
Group 4: Damaged and optimal dosage
Group 5: Damaged and non-optimal therapy
Any laser therapy showed a significant improvement over no laser and the optimal laser (Group 4 with a total dosage of 4 j/cm^2) showed no difference from the uninjured tissue. The image below show the group 2 and group 4 tissue under a polarization microscope.
The following is an except from a USA today article. Please visit the link at the bottom so see the entire article.
What if a cavity could fill itself, a broken tooth regrow? That's the promise of work published today in the journal Science Translational Medicine.
By shining light from a low-powered laser – about the brightness of a sunlit day – researchers were able to turn on a natural healing program and regrow dentin, the material inside a tooth. So far, they can only do this in rodents, but they could receive approval to test it in people within a year.
If it succeeds, the approach might also work for regrowing heart tissue, fighting inflammation and repairing bone and wounds, the researchers say.
"There's potential for this to be broadly useful," said David Mooney, the Harvard University bioengineer, who was the paper's senior author.
The promise is fantastic, said Harold Slavkin, a molecular biologist and professor of dentistry at the Ostrow School of Dentistry at the University of Southern California in Los Angeles. By mimicking a process already found in nature, Mooney's work has the potential to eventually transform medical care, enabling people someday to regrow their own livers, hearts or kidneys, he said.
"Twenty or 30 years from now people may say, 'Isn't it ridiculous that they used to transplant organs from one person to the other,'" Slavkin said.
Co-author Praveen Arany, a dentist and pathologist, said he got interested in the potential healing power of light after hearing anecdotes about light's ability to repair wounds and regrow hair. Laser light at very low frequencies does nothing, and at higher frequencies is commonly used to cut and cauterize tissue, so the dose of light has to be carefully delivered, said Arany, who initiated the research while a student in Mooney's lab.
He spent years carefully calibrating light levels to discover an optimal dose.
At appropriate levels, the light appears to trigger a chemical reaction that releases reactive oxygen species, a potentially damaging type of molecule.
In response to the reactive oxygen, the body's natural healing process activates a protein called Transforming Growth Factor (or TGF)-beta, which plays crucial roles in embryonic development, wound healing and the immune system. The TGF-beta stimulates production of new dentin, the material at the center of the tooth.
Arany and Mooney demonstrated that they can trigger this cascade of events and produce dentin by shining a low-powered laser on a rodent's tooth.
What they can't do yet is stimulate an entire tooth to regrow – the new dentin lacks the structure of a tooth, Mooney said. But Arany, now with the National Institute of Dental and Craniofacial Research, is hopeful of finding a way to get the body to rebuild structures, too.
"If we can figure out a way of activating those (processes), that would be really cool," he said.
Anne George, an endowed professor at the University of Illinois at Chicago, College of Dentistry, praised the work as impressive and important.
"If it works in a clinical trial setting, I think it will be great," she said.
Welcome to the laser-therapy.us research tool. This tool is a searchable collection of technical publications, books, videos and other resources about the use of lasers for photobiomodulation. This tool includes almost the entire U.S. library of medicine research papers on LLLT, videos from Youtube associated with therapy lasers and the tables of contents from laser therapy books. This allows users to search for a keyword or condition and see resources about using lasers to treat that condition. All the resources include links to the original source so we are not making any statement about the use of lasers for treating non-FDA cleared application, we are simple summarizing what others have said. Where every possible, we have included a link to the orginal publication.
Here are some of our favorite queries:
This tool uses a broad match query so:
The results of the search are sorted based on 3 quality factors on a scale of 1 to 10 with 10 being the best score. Originally all the resources were given a 5-5-5 until they could be individually evaluated. These scores are purely opinion and are only used to simplify the rank of the results from more valuable to least valuable. This should not be considered a critique of any work. This system was created to help researchers (including ourselves) find the most usable resources for any cold laser therapy research. The resources are assigned values based on the following 3 factors:
Over the past few years of working with research, we found that a majority of the published resources are lacking in one of these three ranking factors.
The original goal of this research tool was to tie published resources to the protocols in the laser-therapy.us library. This connection allows users to trace each protocol back to a list of resources so the protocol can be researched and improved.
When many of the first research papers were published, the most power laser available for therapy were less than 100mW and many systems had to be pulsed to keep the laser from burning out too quickly. Today, system are available that will deliver up to 60,000mW of continuous output. Because of these power limitation, many early studies were limited to extremely low dosages by today’s standards. It takes a 50mW system 17 minutes to deliver 50 joules at the surface of the skin. If this was spread over a large area of damage or was treating a deeper problem, the actual dosages were much less than 1J/cm2. Today, we know that these dosages typically produce very little or no results.
About 80% of the resources in this database are in the near infrared wavelength. There is also some interest in the red wavelength (600 to 660nm) . Other wavelengths like blue, purple, and green have very little scientific research behind them and have not gotten much traction in the core therapy market with the exception of some fringe consumer products.
This research tool is free to use but we make no claims about the accuracy of the information. It is an aggregation of existing published resources and it is up to the user to determine if the source of the resources has any value. The information provided through this web site should not be used for diagnosing or treating a health problem or disease. If you have or suspect you may have a health problem, you should consult your local health care provider.