Tooth enamel is the hardest substance in the human body, yet once it’s gone, it doesn’t come back. That’s why cavities, sensitivity, and tooth loss are so common. Now, scientists are exploring an unexpected source for repair: keratin, a protein found in hair, nails, skin, and sheep’s wool.
A new study published in Advanced Healthcare Materials suggests keratin extracted from wool can form a protective, enamel-like coating on teeth. Researchers from King’s College London say this approach could lead to sustainable treatments for tooth decay within the next few years. Here’s what they discovered and what it might mean for the future of dental care.
What the research shows on keratin and dental repair
Keratin is a structural protein that gives strength and resilience to biological tissues. By extracting it from wool fibers and applying it to teeth, researchers found it could create a crystal-like coating that mimics natural enamel. When exposed to minerals found in saliva—like calcium and phosphate—the keratin layer attracted these ions, gradually building a strong protective barrier.
This process didn’t just cover the tooth; it encouraged remineralization. Over the course of a month, the keratin coating thickened and hardened, resembling the structure of natural enamel. According to the researchers, this makes it a more durable and natural-looking alternative to traditional dental resins, which are petroleum-based, less resilient, and sometimes toxic.
As coauthor Sara Gamea explained, “not only is it sustainably sourced from biological waste materials like hair and skin, it also eliminates the need for traditional plastic resins“. This makes the research especially promising, since wool is an abundant byproduct of the textile industry.
Tooth decay is the world’s most common oral health condition, affecting an estimated 2 billion people globally. Acidic foods, sugar, and poor oral hygiene slowly erode enamel, leaving teeth vulnerable. Because enamel cannot regenerate on its own, prevention and restorative treatments are the only options. If keratin coatings prove successful in clinical use, they could help close this gap.
What this breakthrough could mean for dentistry
The team behind the study envisions keratin being used in multiple ways. One possibility is a professional treatment, where dentists apply a keratin-based coating directly to damaged enamel. Another is consumer products—such as toothpaste or mouthwash—infused with keratin that reinforces enamel during daily use.
Compared to traditional fillings or crowns, keratin would be less invasive and potentially cheaper. It could also be beneficial for treating early-stage tooth decay, slowing or even preventing the need for drilling and restorative procedures. Since the material closely matches the natural color of enamel, it could also provide a more aesthetic option for patients.
As researcher Sherif Elsharkawy put it, “we are entering an exciting era where biotechnology allows us to not just treat symptoms but restore biological function using the body’s own materials“.
The technology is still in development, and clinical trials will be necessary before it becomes available in dental offices or drugstores. But with further research and industry support, keratin-based products may be ready within the next two to three years.
