A team of interdisciplinary researchers at KU Leuven University have taken a step closer to being able to regrow teeth from the root using 3D printing.

Dental conditions resulting from trauma and developmental anomalies can often affect developing permanent teeth, particularly in children, leading to tissue or even whole tooth loss. To combat this, dental tissue engineering has arisen as a potential means of repair, regeneration, and even tooth replacement through the fabrication of bioengineered “tooth-root”.

In their latest study, the team investigated the 3D printing of chitosan scaffolds derived from animal and fungal sources which could potentially be used in such regenerative dentistry applications in the future.

3D printing and regenerative medicine

The role of 3D printing within regenerative medicine is very much still in its nascent stage, although there have been several promising developments in this area recently.

Starting with human tissue bioprinting breakthroughs, scientists from the University of Buffalo have developed a rapid new 3D bioprinting method slated to bring fully-printed human organs closer to reality, while researchers from Lund University have developed a new 3D printable bioink derived from seaweed and lung tissue that can be used to print constructs resembling human-sized airways capable of supporting cell and blood vessel growth.

3D printer OEM 3D Systems also recently announced a breakthrough in its Print to Perfusion bioprinting platform, which is now able to rapidly produce full-size, vascularized lung scaffolds. As a result, the firm is planning to ramp up its regenerative medicine activities going forwards.

Most recently, Penn State researchers unveiled a 3D bioprinting process capable of printing hard and soft tissue simultaneously to repair skin and bone injuries in a single procedure.

Despite sizeable strides taken in 3D printing for dental applications such as customized alignerspermanent crowns, and dental implants, regenerative medicine developments for dental applications have seen less focus. However, tissue engineering and regenerative medicine have recently been explored for the replacement of injured and missing dental tissues with promising results, such as for regenerative endodontic procedures.

These procedures aim to repair or replace the inflamed or damaged dental pulp – the part in the center of a tooth made up of living connective tissue and cells – in order to restore vascularization, immune response, nerve supply and dentin disposition, which refers to the largest structural component of a tooth that provides support to the enamel.

SEM images showing the scaffolds’ microstructure. Image via KU Leuven.

3D printing the chitosan scaffolds

According to the researchers, chitosan has attracted attention for dental tissue engineering applications due to its antimicrobial and immunomodulatory properties, in addition to its biocompatibility, biodegradability, and gel-forming ability. Chitosan is derived in part from the exoskeleton of crustaceans such as crabs and shrimps, fungi, or insects.

Two types of chitosan were selected for this particular study; chitosan of animal origin and fungal chitosan derived from aspergillus niger, a common species of fungus that causes black mold. Gelatine powder was used as an additional polymer, while genipin and 3-glycidyloxypropyl trimethoxysilane (GPTMS) were used as cross-linking agents.

The chitosan-based scaffolds were prepared via an emulsion freeze-drying technique which involved the design of suitably-sized molds using CAD software and which were then printed using a polyjet 3D printer. The polymer solutions were then prepared and dispensed in the molds before being immediately placed in dry ice for directional freezing to achieve a radially oriented pore structure.

The molds were then freeze-dried for 24 hours and demolded to obtain the final scaffolds. While basic molds were printed this time around, 3D printing allows for the design and production of patient and tooth-specific molds, and therefore scaffolds.

The fungal-derived chitosan scaffold in particular was explored for its desirable properties of reduced risk of allergic reaction, low molecular weight, and enhanced antimicrobial properties.

More generally, the scaffolds were investigated for their direct clinical application in cell-free regenerative endodontics of immature teeth to control infections, induce dentine formation and root formation.

The researchers also believe their tailored scaffolds could be modified through adding inorganic components such as bioactive glass to promote alveolar bone regeneration. Alveolar bone is the thick ridge of bone that contains the tooth sockets, located on a person’s jaw bones.

Going forwards, the team will focus on obtaining a deeper understanding of stem cell and immune cell behaviour in response to the scaffolds, in order to optimize their application in dento-alveolar tissue engineering.

More information on the study can be found in the paper titled “3D printing assisted fabrication of chitosan scaffolds from different sources and cross-linkers for dental tissue engineering,” published in the European Cells and Materials journal. The study is co-authored by M. EzEldeen, J. Loos, Z, Mousavi Nejad, M. Cristaldi, D. Murgia, A. Braem, and R. Jacobs.

Trends are a familiar part of life and most are typically harmless. However, with the rise of social media apps such as TikTok and Twitter, there has also been a concerning rise in dangerous behaviors. While some trends are a fun way to express yourself and connect with other people, they can also lead to long-term health problems — and lately, some trends are specifically leading to damaging things like teeth and gums.

For oral health experts, trying to combat current dental trends circulating the internet, such as brushing with activated charcoal and DIY body modification, is no easy feat. However, it’s imperative that dental professionals stay up to date with current trends in order to better educate their patients to help keep them, and their teeth, healthy.

Missing The Big Picture

One of the trickiest parts of trends, particularly health-related ones, is they often aren’t backed by any sort of real evidence or support. This means that teens and adults scrolling social media might start following dental advice or trends that may actually be harmful. Furthermore, many can overlook the potential risks and fail to consider the overall effect certain trends will have on their body. A good example is apple cider vinegar.

Across several social media sites like Pinterest and Instagram, taking a shot of apple cider vinegar in the name of weight loss is a popular trend. There is limited evidence to support the claim that drinking apple cider vinegar every day will help you lose weight, but what is clear is that it can wear away the enamel on your teeth.

Due to its acidic nature, apple cider vinegar can lead to tooth sensitivity, contribute to decay, and even darken teeth if not properly rinsed off. This kind of important information is often missing from those promoting the weight loss trend though. While there are ways to make vinegar less damaging to your teeth, people rarely research a trend they’ve come across. This can make many trends, not just the apple cider vinegar one, really dangerous long-term.

Another damaging example is the trend of brushing with activated charcoal. This trend spread as a “life hack” for getting whiter teeth without the hassle of going to the dentist or using expensive whitening strips. Brushing with activated charcoal may help whiten teeth as it contains certain compounds that help remove toxins, but it’s also gritty and abrasive. This means regularly brushing with it wears away tooth enamel, making teeth actually appear more yellow. Trends may appear like the quick fix patients are looking for, but oftentimes, they’re merely temporary solutions or actually worsen the problem over time.

Taking Trends Too Far

Body modification isn’t anything new, but the trends circulating on TikTok have left many oral health professionals concerned. From vampire fangs to rhinestones, teens have been gluing accessories to their teeth to switch up their looks or try something new for Halloween. This is problematic for a number of reasons.

For one, super glue and nail adhesive are toxic and harmful to teeth and gums. It can potentially lead to gingival inflammation or the need to get a root canal treatment. Secondly, the products people use to remove the adhesive, such as nail polish remover, can also damage teeth. This isn’t the only teeth modification trend popular on social media either. Another harmful, yet popular trend is the filing of teeth.

Some teens, unhappy with their teeth shape, have recorded themselves filing down their teeth with nail files. As any oral health expert knows, teeth don’t regrow like our nails, and filing can cause permanent sensitivity and nerve damage. While it might seem silly to warn patients against performing body modification at home, there are a lot of different pressures teens face today that can really skew their judgment. Opening up the conversation with understanding can be what saves the next person from making a seriously dangerous and regrettable mistake.

A New Culprit

One trend that’s been around for centuries, unfortunately, is smoking. It takes a different form every so often, for example, vaping has currently taken over the nicotine market. Regardless of how people smoke, it’s never been great for oral health. Vaping is often touted as a healthier alternative to cigarettes, however, studies are suggesting that it can still trigger an inflammatory response within gum tissue, create excess bacteria in the mouth, and lead to mouth dryness.

Vaping is also a major concern as the latest smoking trend is often marketed to younger consumers like teens and young adults with flavors like cotton candy, sour apple candy, and lemonade. Vaping has made its way into content on platforms like TikTok and YouTube as well, making it more likely that impressionable audiences will start the harmful habit. Beyond oral health, vaping may result in serious injury as well. There have been several reports of vapes exploding or catching fire. While addiction is itself a problem, discussing the oral health aspect of vaping with patients may help deter some from starting or help others make the decision to quit.

As an oral health professional, there are many ways to educate patients on the potential dangers of popular trends. While it may not be possible to stop damaging trends from sweeping across social media platforms, it is possible to help patients, of all ages, make better decisions.


Researchers move closer to regenerative dentistry with 3D printing