Science works with enamel to understand and apply it to different areas of our human experience. We look at three recent ways dental enamel is changing the world.
Enamel is something dental professionals work with every day. However, every day, science is working with enamel, too. Some scientists are working to recreate enamel in a lab. Others want to duplicate its properties to enhance ceramic materials that power and protect our world. Some scientists use enamel to study the past and better understand human history.
From working with stem cells to using images of its structure to improve ceramics to using it as a constant in bioarcheological discovery, tooth enamel is more impactful than we might have thought. Let's look at three recent ways dental enamel is changing the world.
Growing Actual Enamel in a Lab
In April 2022, Science Daily reported that a team in Belgium, at Katholieke Universiteit Leuven (KU Leuven) , in cooperation with Hasselt University (UHasselt), developed a 3D research model derived from the stem cells of the dental follicle. Professor Hugo Vankelecom and his team could reliably reproduce the stem cell's properties, including the possibility of producing other dental cells like the ameloblasts that make and secrete tooth enamel.1
Human dental stem cells have been problematic to grow in the lab.1 Enamel is a complicated material. Per Science.org, the structure of enamel has several nested modes of organization, with calcium, phosphorus, and oxygen atoms forming a repeating pattern that makes crystalline wires. Moreover, the enamel-producing cells include a magnesium-rich wire coating that forms a robust material that is further organized into other structures. These complicated patterns and organization have been challenging to mimic for the development of artificial enamel.2
This KU Leuven 3D model is significant in many ways. The ability to produce the 3D model of dental stem cells could lead to a better understanding of human teeth. Another possible implication is the development of lab-grown, natural materials that can restore cavities rather than synthetic ones. Using natural biological tissues for fillings instead of synthetic ones reduces the risk of tooth necrosis that can happen at the tooth composite interface.1
There are other applications this 3D model facilitates, too. People could study the effect of food products on teeth. Toothpaste manufacturers could have access to enamel to optimize the impact of their products for prevention. The researchers also want to use this successful model as a jumping-off point for further research and applications, including developing other tooth structures with the ultimate goal of generating an entire biological tooth.5
Enhancing Clean Energy and National Security
In addition to what it can do for dental restorative materials and prosthetics, studying enamel's structure could also enhance clean energy and national security. Scientists in Idaho seek to understand enamel's unique biological systems, whose characteristics might facilitate toughening monolithic ceramics. These are the ceramics used for soldiers' body armor and clean energy turbine parts.3
The benefits of more formidable body armor for soldiers are apparent. However, the implications for clean energy are more obscure.
So, what is the benefit of more rigid monolithic ceramics for clean energy? The advantage is cost savings for the parts used in turbines. Per the Science X Network's Phys.org, current turbines use monolithic ceramics in their environmental barrier coatings, among other equipment parts. The present ceramics shatter easily when dropped, so manufacturers often reinforce these areas.3 The extra reinforcements add to the expense. Having a more robust ceramic could serve as a substitute, need fewer reinforcements, and reduce costs for equipping in the clean energy field.3
The scientists at Idaho National Laboratory (INL) are using imaging to understand what makes enamel as tough as it is so they can mimic those properties in future iterations of monolithic ceramics. However, unlike the KU Leuven team, the INL team uses 2D imaging using a synchrotron experiment to capture this information. Then, the scientists will transfer the images into a 3D model. A synchrotron accelerates electrons close to the speed of light, which creates a bright light capable of penetrating the enamel sample. Similar to how an x-ray works, the synchrotron light forms an image of the interior of the enamel.3
The researchers then want to study the images to understand enamel better than we do now. Using that information, they can mimic those properties when making monolithic ceramics. They hope these enhanced monolithic ceramics would be lighter and cheaper to manufacture, which benefits clean energy and national defense.3
Facilitating Archaeological Discoveries of Early Humans
Teeth tell us a lot about people today when they sit in our dental chairs. However, they can also tell us about the humans that walked the Earth thousands of years ago.
Archaeology and teeth have a long history. Scientists find teeth in digs because the enamel lasts longer than bones. The enamel tells scientists where and when its previous owner lived, what they ate, and how healthy they were, among other details. Teeth have taught us that humans caught fish off the Croatian Peninsula 10,000 years ago. They also taught us that Neanderthals suffered from malnutrition. Teeth discovered in a cave in China indicate that Homo sapiens were in Asia anywhere from 80,000 to 120,000 years ago, much earlier than scientists thought.4
Discoveries through enamel analysis continue to reveal fascinating new findings regarding early humans. Last year, scientists led by a researcher out of Florida State University re-analyzed data from several smaller experiments. Their deeper dive into the research determined that from 7500 BC to AD 500, the migration rates in the Mediterranean region were about six to nine percent of the population and decreased over time. This research contradicts what most scientists believed about migration in the area, prompting the need for more research.5
Science discovered years ago that the chemistry of human remains could tell much about early humans. However, the chemistry of enamel in teeth (and a small bone in the skull) do not change once a person reaches adulthood. Therefore, studying the chemistry of teeth enamel (in particular, the isotope ratios) and comparing it to the chemistry of other human remains that have chemical changes throughout a human's lifetime can show if a person moved from one area to another after they grew up. In this case, the re-analysis revealed a lack of evidence of mass migration in the area, discounting a long-held belief of regional experts.5
Enamel in ancient teeth continues to upset archaeological assumptions in 2022. In September, ancient teeth discovered in Georgia revealed that early humans settled there nearly 1.8 million years ago. These are the oldest human remains outside of Africa. This discovery could indicate that Georgia was one of the early settlements of early humans after they left Africa.6