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Everything You Need to Know About Cavities - And Why They're Nothing to Fear

Nobody likes sitting in a dentist’s chair, especially to have a cavity fixed. But why does that process take so long? Because fillings take forever to apply -- and your mouth is more complicated than you think.
While your teeth are the hardest substance in your body, they’re not impervious to damage. Your mouth has up to 100 billion bacterial microbes in it every day. Most of them don’t affect your teeth. Some even protect them. But a small percentage of those bacteria combine with sugars to create acid. That acid breaks down the calcium, phosphate and other minerals that make up tooth enamel. “Enamel can repair itself by using minerals from saliva, and fluoride from toothpaste or other sources,” according to the National Institute of Dental and Craniofacial Research. “But if the tooth decay process continues, more minerals are lost [and] the enamel is weakened and destroyed, forming a cavity.”
When that happens, the only way to repair the damage is with a filling. A filling is a material that seals and disinfects the cavity. Fillings can be either an amalgam of metals like mercury, silver, tin and copper, or a tooth-colored composite made of plastic and glass. While amalgams do use mercury, it’s not dangerous: the toxic properties of mercury become inert when combined with the other minerals. Both filling types are equally safe and durable. The only real difference between the two is that amalgam fillings are cheaper and require more of the tooth to be removed.
Regardless of which type of filling you choose, the process for installing it is the same. Once you’re seated in the dentist’s chair, the dentist will place a cotton roll in your mouth near the infected tooth so they have room to work. They’ll also numb the tooth and the area around it, using either a gel or a small injection that will feel like a pinch. The dentist can also give you a small dose of nitrous oxide (laughing gas), if you’re thrilled about the shot. Either way, you have to wait a few minutes for the relaxing effects of either treatment to kick in before beginning treatment. That’s five minutes right there.
Then comes the part you’ve been dreading: the dentist using a small drill to remove all the decay from the cavity:
via GIPHY. Credit: Phoenix AZ Dentist/YouTube
That process is why dentists numb the area. Cavities often develop close to nerves in the gum line. Those nerves are incredibly sensitive, and given that dental drills rotate between 8,000 and 250,000 RPMs -- up to 100 times faster than a home drill -- you do not want them exposed during this procedure. Depending on the amount of oral damage, length of time it’s accumulated, and the size of the cavity, it could take your dentist anywhere from a few seconds to a few minutes to clean the entire area out. The sound of the drill might make your ears ring, but it should not hurt.
After the dentist has drilled the decay out of the cavity, they apply an adhesive to the area. The adhesive needs to be applied twice, once for an initial coating then once more after it dries to make sure the cavity is filled. Next, the dentist injects the filling into the cavity. They may make multiple passes to make sure they’ve got the whole area. All of those steps should take at most, a minute or two. Then, once the filling is injected, the dentist will use a thin tool to pack the filler material into the cavity to make sure there are no cracks or bubbles for bad bacteria to infect. That takes a few seconds and looks like this:
via GIPHY. Credit: Phoenix AZ Dentist/YouTube
Then the dentist uses a curing light to harden the material, which takes about 30 seconds depending on the filling. After the filling hardens, the dentist smoothes out any rough edges with a polishing tool, which can take a minute or two depending on the size of the filling. Lastly, the dentist has you bite down to make sure the filling is secure and you’re not uncomfortable. That takes a few seconds -- unless something needs an adjustments, in which case they’ll need a few minutes to adjust it.
And that’s it! Your tooth is all patched up in 20 minutes and 12 easy steps. Here’s the whole process in two minutes:
Credit: DentalEdu/YouTube
Your jaw might be sore after holding it open for 20 minutes, but that should be the only pain you feel. Think of it this way: repairing a cavity is actually the best time to repair tooth decay. Cavities are much easier -- and far less invasive, costly, and painful -- to treat than more advanced kinds of tooth decay, like root canal damage. Nobody wants a root canal. Take care of your teeth before that happens. It’s quicker than you think.
Feature image credit: Mandy Jouan/Flickr
How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting
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Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
World's oldest work of art found in a hidden Indonesian valley
Archaeologists discover a cave painting of a wild pig that is now the world's oldest dated work of representational art.
Pig painting at Leang Tedongnge in Indonesia, made at 45,500 years ago.
- Archaeologists find a cave painting of a wild pig that is at least 45,500 years old.
- The painting is the earliest known work of representational art.
- The discovery was made in a remote valley on the Indonesian island of Sulawesi.
Oldest Cave Art Found in Sulawesi
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a9734e306f0914bfdcbe79a1e317a7f0"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/b-wAYtBxn7E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
