Teeth whitening agents can cause immense damage: Study

Researchers from the University of Toronto have revealed that teeth whitening products can result in extensive teeth damage. The study was recently published in Nature Scientific Reports.

The study analyzed the dental cell damage caused by the use of carbamide peroxide teeth whitening treatments. It found that a recommended application of just 10 per cent carbamide peroxide gel on teeth lessens enamel protein content, which will gradually result in greater penetration of the whitening agent inside the tooth, soon leading to an increase in dental pulp cell mortality.

Assistant professor at the University of Toronto's Faculty of Dentistry, Laurent Bozec, says that they always took a keen interest in knowing the effect of peroxide-based tooth whitening on tooth structure and how it's been linked to sensitivity. He added that his team wanted to understand the impact on both the enamel and deep inside the pulp. Initially, Bozec had been observing the effect of using hydrogen peroxide in root canal before this study. He found that it was causing collagen locally. This led him to investigate the damage caused when peroxide penetrates through the enamel and dentine before reaching the dental pulp. The researchers found that when carbamide peroxide concentrations were around 35 per cent, the dental pulp cells did not survive.

Bozec said, "Many tooth whitening products have such a high concentration of peroxide gel. For example, 35 per cent, and yet, little is known about what it does to the inside of our teeth." He believes this is the first study of its kind to show the toxic effects of using a tooth whitening paste. He further expects people to opt for a lower concentration of peroxide products if they decide to use teeth whitening products.

The study shows the need for a compromise between the concentrations of peroxide used, exposure time, desired patient outcomes and side effects experienced. The researchers recommend that this be tested in vivo before market release, and patients are made aware of the impact of these procedures on their oral health. Bozec noted the potential to use either non-peroxide based or a controlled peroxide release agent that will not cause the same tooth damage. That, he believes, is the future of tooth whitening.

Bozec conveyed that the study includes contributions from Boriz Hinz, a distinguished professor at the faculty of dentistry. It further involved an international collaboration with students in the doctor of dental surgery program, including Sabrina Nguyen and Ola Redha, a visiting PhD student from the University of London. Redha said she had worked with Professor Bozec at UCL and was fortunate to have been invited on the project.