The field of dentistry has undoubtedly made significant advances over the years. But when you're sitting in the chair, next to that tray of hooks and drills, it feels like things haven't progressed much since medieval times.

Now a promising new drug, initially developed to treat Alzheimer's disease, could reduce or even eliminate drilling and filling altogether.

The new therapy works by stimulating stem cells to fill in cavities with natural dentin, the calcified material that protects the center of the tooth. Dentin is the yellowish and bone-like layer of the tooth just under the enamel, which is hard and translucent.

According to the new research out of King's College London, the process could replace the use of synthetic cements or fillings that dentists typically use to fill a hole or crack in a tooth. The body naturally produces dentin to protect tooth pulp — the innermost tissue in the tooth — but usually only generates a thin layer of the stuff. By accelerating the production of dentin via existing stem cells, the drug can repair even large cavities with the body's own natural tissues.

The actual procedure is much kinder and gentler, too. The treatment is applied by way of small collagen sponges that are packed into the cavity or crack that needs mending. The biodegradable sponges contain the medicine that stimulates renewal of stem cells, and also provide the matrix for regrowing dentin. As the tooth fills itself in, the sponge simply dissolves away. No drills. No picks. No problem.

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Another upside of the procedure is that the medicine in question has already been used in clinical trials to treat neurological disorders including Alzheimer's disease. In terms of FDA regulation, that means the treatment is that much closer to finding its way into your dentist's office. The sponges are clinically approved, too.

"The simplicity of our approach makes it ideal as a clinical dental product for the natural treatment of large cavities," said lead author Paul Sharpe in press materials accompanying the research. "In addition, using a drug that has already been tested in clinical trials for Alzheimer's disease provides a real opportunity to get this dental treatment quickly into clinics."

The study was published today in the journal Scientific Reports.

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