Scientists in Japan are initiating the first human trial for a new drug designed to stimulate the regrowth of lost adult teeth. The treatment, known as TRG035, targets a protein that inhibits tooth development, with the goal of enabling individuals to regrow teeth lost due to decay, gum disease, or injury.
The drug works by blocking the USAG-1 protein, which acts as a brake on the development of teeth from dormant buds. This approach is based on research into conditions like tooth agenesis, a congenital disorder where individuals are born missing one or more adult teeth, and supernumerary teeth, where extra teeth develop.
Tooth agenesis affects approximately one in 20 people, and replacing missing teeth in children presents challenges with current methods like dentures or implants, which often require waiting for jaw growth to complete.
Researchers at Kyoto University Hospital will begin the trial with 24 children diagnosed with oligodontia, a severe form of tooth agenesis where six or more teeth fail to develop. This condition impacts about two in 1,000 individuals.
Mary MacDougall, an expert in genetic tooth disorders from the University of British Columbia, described the trial as a potential "major advancement in the treatment of rare dental disorders." However, she noted that the full process of tooth formation and eruption takes a considerable amount of time.
While the current trial focuses on congenital conditions, the researchers also hope that TRG035 could eventually benefit adults who lose teeth. This application would be more complex, as the tooth buds responsible for lost teeth typically disappear in adulthood, leaving nothing for the drug to stimulate.
Paul Hatton, a professor of biomaterials science at the University of Sheffield, called the approach a "significant step" but cautioned that "it may be decades before such a therapy becomes available." The research team aims to have the TRG035 drug available for patients by 2030.