Researchers in India in collaboration with deep-tech startup Theranautilus have now engineered CalBots—magnetic nanobots that can penetrate deep into dentinal tubules, tiny tunnels in teeth that lead to nerve endings.
These CalBots can then form durable seals for worn enamel, offering lasting relief from tooth sensitivity in just one application.
The study is published in Advanced Science.
The CalBots use a completely new class of bioceramic cement. While bioceramics are widely used in orthopedics and dentistry for their mineralising properties, the team at the Indian Institute of Science (IISc) wanted a solution tailored for hypersensitivity—a formulation that could travel deeper and last longer.
Dental hypersensitivity occurs when microscopic tubules in the dentin—the layer beneath the enamel—become exposed due to erosion or gum recession. These tiny tubules lead directly to nerve endings, which is why even a sip of cold water can cause a sudden, stabbing pain. Most current solutions, such as desensitising toothpastes, offer only surface-level relief and need to be reapplied regularly.
CalBots, however, are different. These 400 nanometer-sized magnetic particles, loaded with a proprietary calcium silicate-based bioceramic formula, are guided by an external magnetic field deep into the exposed tubules. They can reach depths of up to 300–500 micrometers inside the tubules. Once there, the bots self-assemble into stable, cement-like plugs that block the tubules and recreate a durable seal that mimics the natural environment of the tooth.
To test their innovation, the team used human teeth extracted for clinical reasons and created conditions where the dentin was exposed. On these samples, they applied CalBots under a magnetic field for 20 minutes, during which the bots sealed the dentinal tubules by forming deep, stable plugs—a result confirmed through high-resolution imaging.
Encouraged by this, the team progressed to animal trials. It involved giving mice a choice between cold and room-temperature water. Healthy mice preferred both equally. But the mice with induced tooth sensitivity avoided the cold water completely.
“After we treated the sensitive mice with our CalBot solution, they started drinking cold water again—the treatment worked like a charm,” first author Shanmukh Peddi said.
“We saw 100 per cent behavioural recovery. That was a big moment for us.”
