Tag Archives: dentistry

Using an electric toothbrush is actually better, new study finds

Electric toothbrushes have been shown to prevent tooth loss and maintain better oral health.

For something that’s as impactful as dentistry, it’s startling how little science there is in dentistry — up to the point where some have even asked whether dentistry is, itself, a science. When it comes to our teeth and mouth there is a debate about pretty much everything. Even when it comes to the type of toothbrush, things are not settled.

A new contender is the electric toothbrush, which has become ever-present in many parts of the world. Talk to most users and they’ll tell you that using an electric toothbrush feels cleaner, more efficient — few would ever return to a regular toothbrush. But is there any truth to this impression?

Dentists are rather torn on this one, but a new study compared the electric with regular toothbrushes, finding significant advantages to the former.

“Electric toothbrushes have become increasingly popular among all age groups in Germany (2) but few studies have tested their long-term effectiveness,” said study author Dr. Vinay Pitchika, of the University of Greifswald, Germany. “Our study shows that electric toothbrushes are most beneficial in maintaining good oral health and are linked with slower progression of periodontal disease.”

Researchers followed participants for 11 years, with regular dental examinations performed by calibrated and licensed dentists who received prior training from a periodontist.

They focused on periodontal disease, which causes a slow erosion of the bone surrounding the tooth. Periodontal disease creates “pockets” around the teeth, a process which leaves us more vulnerable to tooth loss. Researchers found that participants who use electric toothbrushes have fewer such pockets and better attachment of teeth to the gums and bone. The only group that didn’t benefit significantly from using an electric toothbrush was the one that was already impacted by periodontal disease. Dr. Pitchika said:

“People who already have relatively good oral health and minimal periodontal breakdown appear to profit the most from electric toothbrushing. Electric toothbrushes were much more effective as a preventive tool rather than when periodontitis had already progressed. People with severe periodontitis need periodontal treatment.”

However, researchers also note that when it comes to cavities, there was no substantial difference between the type of toothbrush used. Instead, another factor is probably at play.

“Compared to the type of toothbrush, we presume that fluoride has a major role to play in preventing caries or reducing progression of caries,” said Dr. Pitchika.

Journal Reference: Pitchika V, Pink C, Völzke H, Welk A, Kocher T, Holtfreter B. Long-term impact of powered toothbrush on oral health: 11-year cohort study. J Clin Periodontol. 2019. doi: 10.1111/jcpe.13126.

Mongolian herder removing first premolar, or 'wolf tooth', from a young horse during the spring roundup using a screwdriver. Credit: Dimitri Staszewski. Taylor et al. 2018. Origins of Equine Dentistry. PNAS.

Mongolian herders were the first horse dentists, 3,000 years ago

The open steps of eastern Eurasian may have been the birthplace of veterinary dentistry. It is here that scientists at the Max Planck Institute for the Science of Human History found ancient horse remains whose baby teeth had been removed by the local people. Researchers estimate the remains are from 1300-700 BC, making them the oldest known evidence for veterinary dental care.

Mongolian herder removing first premolar, or 'wolf tooth', from a young horse during the spring roundup using a screwdriver. Credit: Dimitri Staszewski. Taylor et al. 2018. Origins of Equine Dentistry. PNAS.

Mongolian herder removing first premolar, or ‘wolf tooth’, from a young horse during the spring roundup using a screwdriver. Credit: Dimitri Staszewski. Taylor et al. 2018. Origins of Equine Dentistry. PNAS.

Mongolia is known as the land of the horses, where the animals occupy a central role in daily life — and have done so for thousands of years.

“It is not possible to imagine Mongolian history without horses,” says J. Tserendeleg, president of the Mongolian Association for Conservation of Nature and the Environment. “I think it is not possible to view the future of Mongolia without horses as well. Mongolia is not Mongolia without horses.”

It was thanks to horses that the nomadic armies of Mongols were able to breach the Great Wall of China and conquer their way to the heart of Europe, where they became known as “Hell’s Horsemen.” Were it not for horses, legendary thirteenth-century warrior Genghis Khan would have never been able to establish an empire that spanned from Hungary to Korea and from Siberia to Tibet.

Even in the twenty-first century, Mongolia still has a horse-based culture and retains much of its pastoral traditions. Its 2.4 million people are semi-nomadic and support themselves primarily by breeding five domestic species.

It’s no wonder that the Mongols were also probably the first to practice horse dental care, seeing how the animals are central to their livelihoods. Writing in the Proceedings of the National Academy of SciencesWilliam Taylor and colleagues described horse remains from an ancient Mongolian pastoral culture known as the Deer Stone-Khirigsuur Culture. These ancient people are famous for the impressive horse burials they made, which contained from dozens to even thousands of dead horses.

A horse skull placed next to a deer stone in central Mongolia. Ancient and modern Mongolian herders alike revere both. Credit: William Taylor.

A horse skull placed next to a deer stone in central Mongolia. Ancient and modern Mongolian herders alike revere both. Credit: William Taylor.

By analyzing the remains, researchers found that Deer Stone-Khirigsuur people used surprisingly sophisticated veterinary dental procedures to remove baby teeth that would have caused young horses pain or trouble feeding. Previously, research had shown that the same people were the first in eastern Eurasia to heavily use horses for food products and may have been among the first to use horses for mounted riding. Naturally, these developments led to the invention of equine veterinary care.

“We may think of veterinary care as kind of a Western science,” Taylor said in a statement, “but herders in Mongolia today practice relatively sophisticated procedures using very simple equipment. This results of our study show that a careful understanding of horse anatomy and a tradition of care was first developed, not in the sedentary civilizations of China or the Mediterranean, but centuries earlier, among the nomadic people whose livelihood depended on the well-being of their horses.”

It’s also no coincidence that changes in horse dentistry were accompanied by technological improvements in horse control, such as the incorporation of bronze and metal mouthpieces into bridles used for riding. This technology spread into eastern Eurasia during the early first millennium BC, offering riders better control over their horses, which would have offered them the upper hand during warfare. The horses themselves, however, suffered as the metal in the mouthpieces introduces oral problems, including painful interactions with a vestigial tooth, known as a “wolf tooth.” Herders responded by developing methods for extracting the problematic tooth not all that different from the way many veterinary dentists would remove it today.

“In many ways, the movements of horses and horse-mounted peoples during the first millennium BCE reshaped the cultural and biological landscapes of Eurasia. Dr. Taylor’s study shows that veterinary dentistry – developed by Inner Asian herders – may have been a key factor that helped to stimulate the spread of people, ideas, and organisms between East and West,” said Nicole Boivin, Director of the Department of Archaeology at the Max Planck Institute for the Science of Human History.


The first automatic, hands-free toothbrush cleans your teeth in only 10 seconds flat

Brushing twice a day for two minutes, per doctor’s orders, might not seem at all that long but over a year that’s a whole day spent cleaning your teeth. With this in mind, a couple of talented designers got the idea to reinvented brushing by devising an automated toothbrush that cleans all your teeth, at once, in just 10 seconds.

Called the Amabrush, this device is designed to come in contact with all your teeth like a casting mold. It consists of three main components: a bacteria-resistant silicone mouthpiece, a handpiece, and toothpaste capsules. The end result looks something like a pacifier for adults. You just pop one in your mouth and push a button.


Credit: Kickstarter: Amabrush

To clean your dentures, the device induces strong vibrations whose waves vary during the sessions as instructed by an algorithm. Since the automated toothbrush comes in contact with all the teeth in the mouth at the same time, these get cleaned much faster versus brushing single teeth back and forth with a traditional toothbrush, electric or otherwise.

The integrated battery also lasts for 28 sessions meaning you can brush your teeth for at least two weeks, twice a day without needing to recharge.

The mouthpiece is made from bacteria-resistant silicone and features 3D brisltes on both sides (Kickstarter: Amabrush)

The mouthpiece is made from bacteria-resistant silicone and features 3D bristles on both sides. The bristles are comparable to soft-bristled toothbrushes. (Credit: Kickstarter, Amabrush)

Of course, many of you who’ve been brushing teeth the old fashion way might find this device useless. Indeed, there’s nothing wrong with that. Plenty of people brush their teeth the same way it’s been for decades and they have healthy gums and teeth. However, there are many other folks who struggle with their dental routine. For them, the Amabrush might be a godsend.

For now, the people of Amabrush are raising money for their product on Kickstarter. Pre-orders start at 79€ ($90) and things are going well so far. The project has raised over a million euros with 23 days left to go, despite its goal was to raise just 50,000€.

Oldest cavities.

World’s oldest fillings come from the stone age and they’re basically asphalt

People have been going to the dentist for a much longer time than you’d believe. Archaeologists working in northern Italy have found the oldest known dental fillings. They were made from a mix of bitumen, hairs, and plants some 13,000 years ago.

Oldest cavities.

Image credits Stefano Benazzi.

There’s no such thing as a good toothache. That’s why we have dentists, and that seems to have been the case in the stone age, too — although I hear conditions weren’t as good back in the day. Faced with a lack of materials, tools, or you know, any sort of body of literature to guide their steps, ancient dentists had to be creative (they invented a lot of stuff back then). A pair of 13,000-year-old front teeth found in Italy stands testament to what they could achieve with a bunch of stones and bitumen.

Asphalt teeth

The teeth were discovered in the Riparo Fredian site near Lucca, northern Italy. Each one has a large cavity going from the surface all the way through to the pulp. They were probably hollowed out and enlarged with stone tools, judging by microscopic etches and markings on their walls. While poking though these holes, a research team lead by Gregorio Oxilia from the University of Bologna has found residues of bitumen with plant fibers and hairs mixed in. Although very different from what you’d see in today’s fillings, their purpose was probably the same — keep stuff away from the pulp and keep pain to a minimum.

“It is quite unusual, not something you see in normal teeth,” Stephano Benazzi, an archaeologist at the University of Bologna and corresponding author of the paper told New Scientist.

Benazzi noted that the etchings found in these teeth are similar to another set him and the team found in Italy in previous research. That set of teeth was dated as 14,000 years old, the oldest known evidence of dentistry we’ve ever seen. But this is the (new) first time we know of fillings being used.

Fredian upper central incisors.

Image credits Gregorio Oxilia.

It’s probable that the Paleolithic dentist drilled out the cavities and then filled them in — just like his modern counterparts would do. However, he only had tiny stone tools to drill with, probably no anesthetics, and bitumen to use for the fill. The team is unsure as to why the hairs and plant fibers were added to the mix (they did rule out the possibility of them being remains of food since they were added to the area after drilling). One theory is that the plants were chosen for their antiseptic properties, helping to keep the cavity healthy and clean of bacteria. Or the dentists thought fibers would help fix the filling. We don’t yet know.

What’s really striking is the time-frame of the fillings. They’re evidence of relatively advanced knowledge being put to use in fixing an ailment thousands of years before we though they’d become a significant affliction — the change in diet agriculture brought on is thought to have lead to a dramatic increase in cavities. Still, at this time Europe was seeing a lot of people migrating in from the near East, Benazzi adds. The foods they introduced to the continent may have led to more cavities, and then to dentistry.

The full paper “The dawn of dentistry in the late upper Paleolithic: An early case of pathological intervention at Riparo Fredian” was published in the American Journal of Physical Anthropology.



400-year-old dental bridge made out of other people’s teeth is unexpectedly good for its time


Credit: Simona Minozzi

Beneath the centuries-old burial grounds of a monastery in the Tuscan town of Lucca, Italy, archaeologists have come across a rare find: a dental bridge made from five foreign human teeth fastened with a golden band. The wearer of the prosthesis was likely a wealthy man belonging to a powerful family from the 15th century. The researchers who analyzed the bridge were stunned by the craftsmanship noting the design is strikingly similar to modern dental techniques developed no more than 50 years ago.

The prosthesis consists of three central incisors and two lateral canines, all belonging to different individuals. The root apex of each tooth was removed and a cut was made onto the roots so the bridge could fit inside the jaw. To fix the teeth, a golden band was inserted through fissures, as well as two small golden pins for each tooth to lock them in place.

Using a scanning electron microscope, the team of Italian researchers from Pisa University’s paleontology department found the golden band is an alloy made from 73 percent of gold, 15.6 percent of silver and 11.4 percent of copper.

The first dental bridges and dental crowns were allegedly made by the Etruscans as early as 2,500 years ago. These prostheses were employed by the wealthy elite who would often resort to replacing good teeth with a gold bridge to mark their status. Some of the first modern appliances that held loose teeth in place were described by French surgeon Ambroise Paré (1510–1590). Until now, no direct evidence of such devices, be them Etruscan or from the Renaissance era, was found.

Simona Minozzi, one of the lead researchers of the study published in the Clinical Implant Dentistry and Related Research journal, says the dental bridge found in the monastery of S. Francesco at Lucca is the first archaeological evidence of a dental prosthesis using gold band technology.

At the excavation site, two of the tombs belonged to Guinigis, a powerful family who governed the city from 1392 until 1429. The prosthesis, however, was found among the tangled remains of 100 different individuals. The corresponding jaw couldn’t be identified, but it’s safe to say someone of higher status used to wear the prosthesis.

Unlike the Etruscans, the Guinigis seemed to have desperately needed the dental bridge. An examination of the skeletons found inside the tombs revealed many individuals lost teeth to decay and gum infection. The presence of cavities, periodontitis and missing teeth was more than double compared to the Tuscan rural population, the researchers note in their paper.

According to Umberto Pagliaro, a dentist from Florence, the 400-year-old dental bridges are strikingly similar to prostheses made using the modern Maryland bridge technique. Developed at the University of Maryland in the 1970s, the technique involved using a resin bonded bridge with small ‘wings’ on both sides of each adjacent teeth.

Artificial tooth is as good as the real deal

Fewer materials in nature rival the toughness and resilience of a tooth or a seashell, and it’s all due to their unique structure; viewed under powerful enough microscope, they reveal layers upon layers of micro-plates, perfectly aligned and fused together. Material scientists have long sought to produce something that imitates these structures, with comparable properties and complexity, but apart from nacre (mother-of-pearl) they’ve had very little success.

That is, not until now. A group of researchers headed by André Studart, Professor of Complex Materials at the Swiss Federal Institute of Technology in Zurich (ETH), has developed a new method that allows them to imitate the natural model almost perfectly. The team was the first to create a complex piece out of the multiple layers of oriented micro-plates that teeth and shells use.

Cross section of the artificial tooth under an electron microscope (false colour): Ceramic platelets in the enamel are orientated vertically. In the dentin, they are aligned horizontally.
Image credits: Hortense Le Ferrand/ETH Zürich

Line them up then stack them down

They christened their method the magnetically assisted slip casting (MASC) method.

“The wonderful thing about our new procedure is that it builds on a 100-year-old technique and combines it with modern material research,” says Studart’s doctoral student Tobias Niebel, co-author of a study just published in the specialist journal Nature Materials.

The main difficulty of producing an enamel-like material lies in aligning the individual layers of micro-plates to different orientations. But the team came up with a plan, a plan so cunning you could pin a tail on it and call it a weasel: the process uses a plaster cast that the researchers created to serve as a mold into which they pour a suspension of magnetized ceramic micro-plates, such as aluminium oxide micro-plates. The plaster mold is full of pores that absorb the liquid from the suspension, solidifying the material from the outside in. During the casting, the ETH team subjects the mold and plates to a strong magnetic field, under which they act like little compass points, aligning perfectly. The field’s orientation is changed at regular intervals, moving the plates still in suspension, leaving the ones that have already solidified undisturbed.

Through the composition of the suspension and the direction of the platelets, a continuous process can be used to produce multiple layers with differing material properties in a single object. This creates complex materials that are almost perfect imitations of their natural models, such as nacre or tooth enamel.

“Our technique is similar to 3D printing, but 10 times faster and much more cost-effective,” says Florian Bouville, a post-doc with Studart and co-lead author of the study.

Utilizing the MASC method, they produced an artificial tooth with a microstructure mimicking that of a real tooth. The outer layers, corresponding to enamel, are hard and structurally complex, with deeper layers being more tough, just like dentine. The first suspension, used for enamel, contained glass nanoparticles and the aluminium oxide plates were aligned perpendicular to the surface. After it hardened, a second suspension was poured. It contained no glass, and the plates were aligned horizontally to the surface of the tooth. The tooth was then cooked at 1,600 degrees to compact and harden the material — a process known as sintering. The last step involved filling any pores that remained with a synthetic monomer used in dentistry, which polymerizes after treatment.

I can’t believe it’s not butter a tooth

The left structure is showing the natural tooth in its gypsum mold, the middle structure is the artificial tooth (sintered but not yet polymer infiltrated). The model on the right has been sintered and polymer infiltrated. It is embedded in a “puck” to enable polishing and coated with Platinum to prevent charging in the electron microscope.
Image credits: Tobias Niebel/ETH Zurich

“The profile of hardness and toughness obtained from the artificial tooth corresponds exactly with that of a natural tooth,” says a pleased Studart.

The procedure and the resulting material lend themselves well to applications in dentistry. However, as Studart points out, the technology is still at an early proof-of-concept stage, and the study was just meant to show that the natural structure of teeth can be reproduced in a laboratory. Further refining and improving is required to make the most out of their work.

“The appearance of the material has to be significantly improved before it can be used for dental prostheses.”

Nonetheless, the finished tooth shows that a degree of control over the microstructure of a composite material can be achieved to a level which was previously only seen in living organisms. One part of the MASC process, the magnetisation and orientation of the ceramic platelets, has already been patented.

However, the new production process for such complex biomimetic materials also has other potential applications. For instance, copper platelets could be used in place of aluminium oxide platelets, which would allow the use of such materials in electronics.

“The base substances and the orientation of the platelets can be combined as required, which rapidly and easily makes a wide range of different material types with varying properties feasible,” Studart concludes.

The full paper is available on Nature.com.


What Is Gum Disease And How Do You Treat It?

Gum disease is a common problem and its symptoms are unpleasant, for example swollen and sore gums. When you brush your teeth you could be spitting out a little blood. Your breath might be less than fresh and you may suffer minor aches and stinging.

But thankfully gum disease, known to dentists as gingivitis or periodontal disease, is pretty easy to stave off… providing your oral hygiene is up to scratch.

Swollen, sore and infected gums are a very common complaint, affecting a little under 20 per cent of the world population. According to the NHS gum disease webpage, figures for the UK are higher, and oral hygienists agree that half our adult population will have at some time suffer from some form of gum disease.  Good news for the kids, here: it’s a lot less common in children.


Image: comfortdds.com

The severest cases of periodontitis, which affect between ten and 15 per cent of the UK population, cause the biggest problems (NHS stats 2014).  The tissue which supports the teeth, and holds them in place in the mouth, can be damaged. Untreated, this can lead to the bone in your jaw becoming decayed. Small spaces might open up between the gum and teeth, and after a while your teeth might loosen and fall out.

Check your gums

The simplest and most effective way to guard against gum disease is to clean your teeth regularly. Gum disease is caused by the harmful bacteria found in the built-up deposits of plaque which stick to the teeth. So brush away – or risk the plaque irritating your gums, causing soreness and inflammation.

Whether you have dental insurance or not, you should visit your dentist if you find your gums are bleeding or sore while brushing. He or she can give your teeth a rigorous clean and scrape away any hardened plaque, or tartar, that has been building up.

More severe cases might require tougher treatment, possibly even going as far as to require surgery.

But in the vast majority of cases, your dentist will sort you out with a good clean. Expect to receive some advice on how to clean your teeth more thoroughly, too, to prevent that potentially harmful plaque from building up again in the future.

Those blessed with healthy teeth and gums might only have to visit the dentist every six months or so for a check-up. But if you have had gum disease problems in the past, or if you are going through a bit of a gum disease phase, you might need to visit your dentist more frequently – and he or she will be able to best advise on how to organise this.

Also, some people will be more at risk of developing gum disease than others. Smokers, for instance, or diabetics, might benefit from more frequent oral hygiene check-ups.

So, if you think you may have gum disease then don’t hesitate to book an appointment to see your dentist and get those problems sorted before it gets any worse.


This is a microphotograph of the tooth crown in occlusal view with indication of the surface covered by beeswax (within the yellow dotted line). (c) Bernardini F, Tuniz C, Coppa A, Mancini L, Dreossi D, et al.

Oldest dental filling is beeswax

Researchers have found what’s believed to be the oldest dental feeling in history, dating from the stone age. The find was made after the jaw-bone of a middle-aged man dating back from 6,500 years ago had a tooth filled with beeswax, pushing back early human dentistry.

This is a microphotograph of the tooth crown in occlusal view with indication of the surface covered by beeswax (within the yellow dotted line). (c) Bernardini F, Tuniz C, Coppa A, Mancini L, Dreossi D, et al.

This is a microphotograph of the tooth crown in occlusal view with indication of the surface covered by beeswax (within the yellow dotted line). (c) Bernardini F, Tuniz C, Coppa A, Mancini L, Dreossi D, et al.

The jaw-bone was discovered some 100 years ago in modern Slovenia, and most likely belonged to a man between the age of 24 and 30. The dental work gathered dust in a local museum ever since, without attracting a great deal of attention, until researchers gave it a closer look in more recent times. Evidence suggests that the filling was made around the time of the man’s death, however it’s yet unclear whether the beeswax filling was made prior or after death.

If the latter is the case, than the filling may have been ritualistic in nature.  However, the researchers  led by Federico Bernardini and Claudio Tuniz of the Abdus Salam International Centre for Theoretical Physics in Italy in cooperation with Sincrotrone Trieste and other institutions, have found that the tooth exhibits some severed wear. This may hint towards the greater possibility of the filling being used as a dental treatment, alleviating pain and desensitizing the vertical crack in the enamel and dentin layers of the tooth.

As for the causes which may have lead to the tooth decay, the researchers involved in the study believe non-alimentary activities, possibly such as weaving, generally performed by Neolithic females, might be a factor. Concerning ancient dental practices, this isn’t the first evidence of early tooth treatment. In 2001, a graveyard in Pakistan dating as far back as 9,000 years yielded up 11 human molars showing drill holes; no fillings were present however.

“This finding is perhaps the most ancient evidence of pre-historic dentistry in Europe and the earliest known direct example of therapeutic-palliative dental filling so far,” says co-author Federico Bernardini.

The findings were reported in the journal PLOS One.