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Stem cells help restore damaged teeth, new study finds
Stem cells have endless uses. This study suggests they can even bring half dead teeth back to life.

- A new study demonstrates that stem cells from baby teeth can be used to repair damaged permanent teeth in young children.
- The findings suggest a new treatment for childhood dental issues may be around the corner.
- The treatment's potential applications go much further than just dental health.
Half of all children suffer some kind of dental injury while young. Sometimes the damage isn't to the baby teeth they will lose anyway, but to the permanent adult teeth lying below the gums that they will need for the rest of their lives. In some cases, trauma can cut off the blood supply to a tooth and rot out the living pulp inside it; a condition called "pulp necrosis." This condition often leads to the loss of the tooth. While treatment exists, it is often unsatisfactory.
But stem cells might do the trick.
Few people really like going to the dentist. This new treatment might reduce the need for the less pleasant treatments.
(Getty images)
A new clinical trial by Yan Jin, Kun Xuan, and Bei Li of the Fourth Military Medicine University in Xi'an, China and Songtao Shi of the University of Pennsylvania's School of Dental Medicine demonstrates how to repair teeth suffering from pulp necrosis by taking stem cells from the patient's baby teeth.
The study, carried out in China on 40 children who had both damaged adult teeth and baby teeth that had yet to fall out, was published in the journal Science Translational Medicine. The test subjects were selected to either receive the new treatment or an older treatment called apexification, which attempts to address the issue by encouraging root development. This was considered the control group.
The patients who received the stem cell treatment, called human deciduous pulp stem cell (hDPSC) treatment, had pulp tissue taken out of one of their healthy baby teeth. This pulp is rich in stem cells. The cells were grown in a lab and then placed into the injured adult tooth. The hope was that the stem cells would encourage the growth of new pulp inside the tooth.
Follow-ups were carried out for up to three years. The patients who had received the hDPSC treatment showed better blood flow in their teeth, better root systems, and thicker dentin than the patents who underwent the traditional procedure. They also had recovered sensation in their teeth, while the control group had not. The use of a patient's own cells in the treatment also reduced the risk of their body rejecting the therapy, making the concept even more attractive.
"This treatment gives patients sensation back in their teeth. If you give them a warm or cold stimulation, they can feel it; they have living teeth again," Dr. Shi told Penn Today. "For me, the results are very exciting. To see something we discovered take a step forward to potentially become a routine therapy in the clinic is gratifying."
What applications will this have?
Before you get too excited, the research is still in the early stages. The problem of how to treat adults with dental problems after they have no more baby teeth to take stem cells from still remains unsolved. It will also be some time before the dental treatment gets approval for use in the United States, so don't hold your breath for getting a stem cell boost to your smile just yet.
Many children suffer dental injuries that can have a lasting impact later in life, often leading to the loss of permanent teeth. This can lead to a loss of self-esteem, speech issues, and jaw problems. This new treatment option, while currently limited to very young children, could provide a breakthrough in dental care. The potential applications for treating systemic diseases such as lupus are also promising.
"We're really eager to see what we can do in the dental field, and then building on that to open up channels for systemic disease therapy," Dr. Shi said.
Scientists find 16 'ultra-black' fish species that absorb 99.9% of light
These alien-like creatures are virtually invisible in the deep sea.
A female Pacific blackdragon
- A team of marine biologists used nets to catch 16 species of deep-sea fish that have evolved the ability to be virtually invisible to prey and predators.
- "Ultra-black" skin seems to be an evolutionary adaptation that helps fish camouflage themselves in the deep sea, which is illuminated by bioluminescent organisms.
- There are likely more, and potentially much darker, ultra-black fish lurking deep in the ocean.
The Pacific blackdragon
Credit: Karen Osborn/Smithsonian
<p>When researchers first saw the deep-sea species, it wasn't immediately obvious that their skin was ultra-black. Then, marine biologist Karen Osborn, a co-author on the new paper, noticed something strange about the photos she took of the fish.</p><p style="margin-left: 20px;">"I had tried to take pictures of deep-sea fish before and got nothing but these really horrible pictures, where you can't see any detail," Osborn told <em><a href="https://www.wired.com/story/meet-the-ultra-black-vantafish/" target="_blank">Wired</a></em>. "How is it that I can shine two strobe lights at them and all that light just disappears?"</p><p>After examining samples of fish skin under the microscope, the researchers discovered that the fish skin contains a layer of organelles called melanosomes, which contain melanin, the same pigment that gives color to human skin and hair. This layer of melanosomes absorbs most of the light that hits them.</p>A crested bigscale
Credit: Karen Osborn/Smithsonian
<p style="margin-left: 20px;">"But what isn't absorbed side-scatters into the layer, and it's absorbed by the neighboring pigments that are all packed right up close to it," Osborn told <em>Wired</em>. "And so what they've done is create this super-efficient, very-little-material system where they can basically build a light trap with just the pigment particles and nothing else."</p><p>The result? Strange and terrifying deep-sea species, like the crested bigscale, fangtooth, and Pacific blackdragon, all of which appear in the deep sea as barely more than faint silhouettes.</p>Pacific viperfish
David Csepp, NMFS/AKFSC/ABL
<p>But interestingly, this unique disappearing trick wasn't passed on to these species by a common ancestor. Rather, they each developed it independently. As such, the different species use their ultra-blackness for different purposes. For example, the threadfin dragonfish only has ultra-black skin during its adolescent years, when it's rather defenseless, as <em>Wired</em> <a href="https://www.wired.com/story/meet-the-ultra-black-vantafish/" target="_blank">notes</a>.</p><p>Other fish—like the <a href="http://onebugaday.blogspot.com/2016/06/a-new-anglerfish-oneirodes-amaokai.html" target="_blank">oneirodes species</a>, which use bioluminescent lures to bait prey—probably evolved ultra-black skin to avoid reflecting the light their own bodies produce. Meanwhile, species like <em>C. acclinidens</em> only have ultra-black skin around their gut, possibly to hide light of bioluminescent fish they've eaten.</p><p>Given that these newly described species are just ones that this team found off the coast of California, there are likely many more, and possibly much darker, ultra-black fish swimming in the deep ocean. </p>When does an idea die? Plato and string theory clash with data
How long should one wait until an idea like string theory, seductive as it may be, is deemed unrealistic?
- How far should we defend an idea in the face of contrarian evidence?
- Who decides when it's time to abandon an idea and deem it wrong?
- Science carries within it its seeds from ancient Greece, including certain prejudices of how reality should or shouldn't be.
Plato used the allegory of the cave to explain that what humans see and experience is not the true reality.
Credit: Gothika via Wikimedia Commons CC 4.0
<p>When scientists and mathematicians use the term <em>Platonic worldview</em>, that's what they mean in general: The unbound capacity of reason to unlock the secrets of creation, one by one. Einstein, for one, was a believer, preaching the fundamental reasonableness of nature; no weird unexplainable stuff, like a god that plays dice—his tongue-in-cheek critique of the belief that the unpredictability of the quantum world was truly fundamental to nature and not just a shortcoming of our current understanding. Despite his strong belief in such underlying order, Einstein recognized the imperfection of human knowledge: "What I see of Nature is a magnificent structure that we can comprehend only very imperfectly, and that must fill a thinking person with a feeling of humility." (Quoted by Dukas and Hoffmann in <em>Albert Einstein, The Human Side: Glimpses from His Archives</em> (1979), 39.)</p> <p>Einstein embodies the tension between these two clashing worldviews, a tension that is still very much with us today: On the one hand, the Platonic ideology that the fundamental stuff of reality is logical and understandable to the human mind, and, on the other, the acknowledgment that our reasoning has limitations, that our tools have limitations and thus that to reach some sort of final or complete understanding of the material world is nothing but an impossible, <a href="https://www.amazon.com/dp/B01K2JTGIA?tag=bigthink00-20&linkCode=ogi&th=1&psc=1" target="_blank" rel="noopener noreferrer">semi-religious dream</a>.</p>Can you still spread coronavirus after getting the vaccine?
The vaccine will shorten the "shedding" time.
The best defense against authoritarianism? More educated citizens.
For democracy to prosper in the long term, we need more people to reach higher levels of education.
