Following trauma or an infection, the inner, soft pulp of a tooth can become exposed and infected. In order to protect the tooth from infection, a thin band of dentin is naturally produced and this seals the tooth pulp, but it is insufficient to effectively repair large cavities.

Currently dentists use human-made fillings, such as resin composites or amalgams, to treat these larger cavities and fill holes in teeth. This restoration merely replaces the lost or infected tooth structure, meaning that the normal mineral level of the tooth is never completely restored only replaced.

However, in a paper published in Scientific Reports, scientists from the Dental Institute at King’s College London have proven a way to stimulate the stem cells contained in the pulp of the tooth and generate new dentin, a mix of inorganic and organic layers that protects the tooth — in large cavities, potentially reducing the need for fillings or crowns.

The novel, biological approach could see teeth use their natural ability to repair large cavities rather than using fillings, which are prone to recurrent decay and often need replacing after a number of years. When fillings fail or infection occurs, dentists have to remove and fill an area that is larger than what is affected. This new method encourages natural tooth repair, it could eliminate all of these issues, providing a more natural solution for patients.

Significantly, one of the small molecules used by the team to stimulate the renewal of the stem cells included Tideglusib, which has previously been used in clinical trials to treat neurological disorders including Alzheimer’s disease. This presents a real opportunity to fast-track the treatment into practice.

Using biodegradable collagen sponges to deliver the treatment, the team applied low doses of small molecule glycogen synthase kinase (GSK-3) to the tooth. They found that the sponge degraded over time and that new dentine replaced it, leading to complete, natural repair. Collagen sponges are commercially-available and clinically-approved, again adding to the potential of the treatment’s swift pick-up and use in dental clinics.