The Korean National Police Agency has charged an international dental chain with using a dangerous, illegal teeth-whitening product, according to an article in the Wall Street Journal.
United Dental Clinic, a dental network with five of its 120 offices in the U.S., allegedly treated patients with a gel containing very high amounts of hydrogen peroxide typically designated for industrial use.
According to the article, 21 United Dental clinics used the gel with a 34.5% concentration of hydrogen peroxide, more than double the 15% allowed by Korean regulations. More than 4,000 people were treated with the product, which could cause sensitive teeth and shooting pains, among other harmful side effects. The staff wrote prescriptions for painkillers to those who experienced pain after treatment, the Journal reported.
The chairman of the group, Kim Jong-hoon, reportedly has fled the country and a warrant has been issued for his arrest.
