Scientists at the Indian Institute of Science, Bengaluru have come up with a futuristic fix: CalBots – tiny magnetic “robots” so small you could fit thousands of them across the width of a single hair.
Published Aug 12, 2025 | 7:00 AM ⚊ Updated Aug 12, 2025 | 7:00 AM
Desensitising toothpaste coat the surface but don’t go deep enough.
Synopsis: Scientists at the IISc Bengaluru, in collaboration with startup Theranautilus, have developed magnetic nanobots designed to travel deep into dentinal tubules and seal the channels that cause tooth sensitivity. These bots, dubbed CalBots, deliver a specially formulated calcium silicate-based bioceramic cement that creates a durable plug, potentially providing long-lasting relief from pain triggered by cold or hot stimuli.
If a sip of cold water or a bite of ice cream makes you wince in pain, you’re not alone. Tooth sensitivity affects millions. Most people simply reach for special toothpaste that offers some relief, but only for a short while.
Now, scientists at the Indian Institute of Science (IISc) in Bengaluru, along with the startup Theranautilus, have come up with a futuristic fix: CalBots – tiny magnetic “robots” so small you could fit thousands of them across the width of a single hair.
Microscopic images of CalBots inside teeth. (Supplied)
These nanobots can travel deep into the tooth, far deeper than toothpaste ever could, to seal the tiny channels (called dentinal tubules) that lead to the nerves. Once sealed, those sharp jolts of pain when you have something cold or hot could become a thing of the past.
“We didn’t want to create just a slightly better version of what’s already out there,” says Shanmukh Peddi, the lead researcher. “We wanted something that solves the problem in a way no one has tried before.”
The research has been published in the journal Advanced Science.
The researchers explain that beneath the hard enamel of our teeth lies a softer layer called dentine. It contains microscopic channels, called dentinal tubules, that lead straight to the tooth’s nerve endings.
When enamel wears down or gums recede, these tubules get exposed. Even a sip of cold water can send pain shooting to the nerves. Current treatments, the researchers say – such as desensitising toothpaste – coat the surface but don’t go deep enough, and the effect wears off.
However, CalBots are guided by an external magnetic field to travel 300-500 micrometres inside the tubules.
Dentinal tubules are like micro-sized straws inside your teeth. When enamel wears down or gums recede, these tubules get exposed – and anything cold, hot, or sweet travels straight to the nerves.
CalBots, guided by a magnetic field, can go deep inside these straws (up to half a millimetre) carrying a special tooth-healing material. They then form a solid, natural-like plug to block them for good.
Once inside, the bots release a “new type of calcium silicate–based bioceramic cement designed especially for hypersensitivity.”
(LTR) Researchers Prajwal Hegde, Peddi Shanmukh, Debayan Dasgupta, Ambarish Ghosh. (Supplied)
Bioceramics are already used in dentistry and orthopaedics for their mineralising properties, but this new formula is tailored to set longer and penetrate further.
“We wanted a technology to solve a real problem in a way that no one has attempted before,” the authors added.
The CalBots then self-assemble into cement-like plugs that block the tubules, recreating a durable seal that mimics the tooth’s natural state.
To test the new innovation, the team began with extracted human teeth. They exposed the dentine, applied CalBots under a magnetic field for 20 minutes, and used high-resolution imaging to confirm the tubules were sealed with deep, stable plugs.
Next came animal trials, in collaboration with IISc’s Centre for Neuroscience. Mice with normal teeth drank both cold and room temperature water equally. But when researchers induced tooth sensitivity, the mice avoided cold water.
However, the authors say that the tests have been promising. In one experiment, mice with sensitive teeth refused to drink cold water. But after a 20-minute CalBot treatment, they started sipping happily again. “It worked like a charm. We saw 100 percent recovery,” Peddi says in a press statement.
The materials used to make CalBots are safe and already approved for use in the body. “This is a compelling example of what nanorobotics can do for healthcare,” says Ambarish Ghosh, Professor at IISc.
The team hopes this technology could one day be used in dental clinics everywhere – giving patients quick, long-lasting relief in just one visit.
