As an adult human, you probably already have some knowledge about tooth regeneration. Around age six, most of us start losing baby teeth in a process called eruption, swapping our first set for more durable, permanent teeth. This process is reminiscent of animals that continuously grow new teeth, like sandbar sharks that grow thousands of serrated teeth over time, and rabbits whose incisors continuously grow as they wear down from roughage. If fish, bunnies, and children can do it effortlessly, why don’t adults naturally shed their aging molars and grow new ones? How close is science to making this a reality? I sense a toothache approaching…
To understand why humans don’t naturally regrow teeth, we need to delve into a brief history lesson provided by Dr. Ophir Klein, a professor at the University of California, San Francisco, specializing in orofacial sciences and pediatrics.
According to Klein, millions of years ago, animals diverged into invertebrates and vertebrates. The earliest vertebrates were reptile-like creatures, leading to the evolution of mammals, dinosaurs, birds, and amphibians. Teeth became essential in the vertebrate mouth, but their origin remains unclear—whether they started inside the mouth or as migrated scales similar to fish. Early teeth were simple, resembling those found in fish today. The stem-cell-driven process in fish allows continuous tooth replacement when needed. However, with the evolution of mammals and humans, teeth became more complex, with different types serving specific functions. Humans, unlike some mammals, did not evolve continuously growing teeth due to the loss of special progenitor cells necessary for tooth replacement.
So, the question remains: How close are we to overcoming this evolutionary limitation and regrowing permanent human teeth? One potential approach involves a combination of synthetic materials and stem cells to facilitate tooth regrowth.
According to Klein, progress has been made in creating artificial enamel and utilizing tooth stem cells to regrow the living part of the tooth, potentially leading to bioengineered new teeth. While Klein believes this breakthrough may not happen in the next five years, he acknowledges the rapid pace of advancements and anticipates it could occur within the next couple of decades.
Although the concept may seem futuristic, the potential for tooth regeneration is a topic worth exploring.
Dr. Salvador Nares, a professor at the University of Illinois, Chicago’s College of Dentistry, highlighted the challenges associated with integrating regrown teeth into the jawbone, emphasizing the need for accurate morphology and functionality. Current research focuses on utilizing stem cells from erupted baby teeth to manufacture tooth components.
Advancements in fields like scaffolds, bio-printing, and gene editing, particularly CRISPR technology, offer promising avenues for tooth regeneration. Gene editing, in particular, shows potential in using patients’ own cells to guide tissue repair and regeneration.
Research on antibody drugs that could stimulate human tooth growth also shows promise, although concerns about potential side effects and off-target effects need to be addressed.
While the journey towards tooth regeneration may be long and complex, the potential benefits are significant. With ongoing research and technological advancements, the possibility of regrowing teeth or other tissues is becoming more feasible.
In the meantime, maintaining good oral hygiene and caring for your existing teeth is crucial for overall health. Regular cleanings, brushing, and flossing are essential for preserving the natural dentition we are born with.
This article is part of Popular Science’s Ask Us Anything series, where we answer your burning questions, from the ordinary to the extraordinary. Have a question you’ve always wanted to ask? Ask us.
