According to a study by researchers at the Indian Institute of Science (IISc) Bangalore, nano-sized robots using magnetic fields can help kill bacteria deep in the teeth and increase the success of root canal treatments. Root canal treatment is routinely performed to treat dental infections in millions of patients. This procedure involves removing the infected soft tissue inside the tooth, called the pulp, and flushing the teeth with antibiotics or chemicals to kill the bacteria that cause the infection.
However, many times, treatment fails to completely remove all bacteria – especially antibiotic-resistant bacteria such as Enterococcus faecalis – which are hidden in the microscopic canal of the tooth known as the dentinal tubules. “Dental tubules are very small, and deep inside the bacterial tissue.” .
In a study published in the journal Advanced Healthcare Materials, researchers designed helical nanobots made of iron-coated silicon dioxide, which can be controlled using a device that creates a low-intensity magnetic field. These nanobots were then injected into the extracted tooth sample and their movements were tracked using a microscope.
By changing the magnetic field frequency, the researchers were able to move the nanobots arbitrarily and penetrate deeper into the dental tubules.
“We have also established that we can recover them … we can bring them back from the patient’s teeth,” said Srinivas. “Significantly, the team was able to conduct a magnetic field to heat the surface of the nanobots, which could kill nearby bacteria. No other technology on the market can do this at the moment,” said Debayan Dasgupta, a research associate at CeNSE and another co-founder of Theranatilus.
Previously, scientists have used ultrasound or laser pulses to create shockwaves in liquids used to flush bacteria and tissue debris to improve the efficiency of root canal treatment. However, these pulses can only penetrate a distance of 800 micrometers and their energy spreads rapidly. Nanobots were able to penetrate much more – up to 2,000 micrometers.
Using heat to kill bacteria provides a safer alternative to harsh chemicals or antibiotics, the researchers said. They tested dental nanobots on rat models and found them to be safe and effective. Researchers are also working on a new type of medical device that could easily fit inside the mouth and allow dentists to inject and manipulate nanobots inside the teeth during root canal treatment.
“We are very close to installing this technology in a clinical setting, which was considered the future three years ago. It is a pleasure to see how a general scientific curiosity is transformed into a medical intervention that could affect millions of people in India alone, ”added Ambrish Ghosh, a professor at CeNSE.