A study conducted by researchers at the University of Toronto highlights the enormous damage that can be caused by common teeth whitening agents.
Recently published in Nature Scientific Reports , the study evaluated the damage to dental cells caused by the use of carbamide peroxide teeth whitening treatments.
The study found that a recommended application of only 10% carbamide peroxide gel on teeth (formulations that also contain 35% carbamide peroxide gel are on sale online) reduces the protein content of the enamel by up to 50%.
Whiteners literally wreak havoc on your teeth
“We have always been interested in the effect of whitening teeth peroxide based. In particular the effect on tooth structure and its link with sensitivity,” he says Laurent Bozec, author of the study and associate professor at the Faculty of Dentistry at the University of Toronto.
In this research we wanted to further understand the impact on the enamel itself and deep within the pulp.
Laurent Bozec
The research
Prior to this study, Bozec examined the effect of using hydrogen peroxide in root canal treatment. On that occasion he discovered that it was causing damage to the collagen locally. This led him to investigate how the peroxide in tooth whiteners penetrates through enamel and dentin before reaching the dental pulp. And he has seen what damage he can cause along the way.
The study found that the loss of the protein content of the enamel leads to greater penetration of the whitening agent into the tooth and can lead to increased mortality of dental pulp cells.
The team used an internal dentin perfusion chamber to make the measurements. At carbamide peroxide concentrations around 35%, the researchers found that dental pulp cells did not survive the exposure.
Photo courtesy of the Bozec Lab
Teeth whiteners: extensive and still unknown damage
“Many home teeth whitening products have a really high concentration of peroxide gel, yet little is known about what it does inside our teeth,” Bozec says. “We believe this is the first study of its kind to show the extremely toxic effects of using a teeth whitening agent. Our hope is that people will opt for a lower concentration of peroxide if they choose to use a teeth whitening product.”
Although using a lower concentration of peroxide (e.g. 5%) would be less harmful to dental cells, consumers often opt for higher peroxide concentrations. Why? Obviously, to obtain an immediate whitening effect.
The researchers' recommendations
The study shows the need for a compromise between the peroxide concentrations used, the exposure time, the desired patient outcomes and the side effects encountered.
This mix should be tested in vivo before release on the market and patients should be informed of the impact of these procedures on their oral health, the researchers recommend.
“There is the option of using a non-peroxide-based or controlled peroxide-releasing agent that won't cause the same damage,” Bozec says. “I believe this is the future of teeth whiteners.”
