A Cork-Sized Robot May One Day Prepare Your Tooth for a Crown in a Single Visit

Getting a dental crown typically means at least two appointments: one to prepare the tooth, and another to place the permanent restoration after it has been fabricated.

Researchers at the University of Basel have developed a miniature dental robot that could one day automate that preparation step, potentially reducing the number of visits a patient needs to complete the process.

The device, called the Miniature Intraoral Robot — or MIR — is a compact robotic system designed to scan and prepare a tooth for a crown during a single appointment. Roughly the size of a wine cork, the prototype fits comfortably inside the patient's mouth.

A custom-fitted dental splint, produced from a digital scan of the patient's teeth, anchors the robot in place. If the patient moves their head during treatment, the splint allows the device to move with them.

The motors and control system are positioned outside the mouth and connected through flexible drive shafts, cables, and tubes.

The robot prepares the tooth in two steps: a wider drill first reduces the upper surface, and a longer, thinner drill then shapes the sides. Notably, the system achieved this without any sensors to measure or correct its position in real time — and yet, in laboratory tests, the positional error was less than 0.2 millimeters.

Researchers believe future versions equipped with cameras and advanced sensors could further improve precision while allowing the robot to continuously monitor its position throughout a procedure.

MIR remains in the prototype stage, but the technology highlights the growing role of robotics in restorative dentistry.

The study was published in IEEE Transactions on Medical Robotics and Bionics and was conducted in collaboration with the University of Zurich, the University of Bern, and a Swiss dental technology company.

The researchers envision a workflow in which, after a single scan, the dentist plans the robot's movements and orders the permanent crown immediately, rather than waiting for a follow-up appointment.

Clinical use in humans is still some years away, but the early laboratory results have drawn attention from the broader dental research community.