Dental student Jennifer Day checks her drilling technique on a new advanced simulation unit.
They know the drill
Computerized mannequins give dental students instant feedback
By Deane Morrison
Bending over the wide-open mouth below her, a second-year dental student begins to drill a tooth. Everything is going smoothly when a beep sounds. Then another. And another. Oops. She was slumping. The student corrects her position and goes on, confident she'll get no complaints from the patient. But she'll get plenty of feedback. The patient is a mannequin in the School of Dentistry's advanced simulation lab, equipped with 3-D motion detectors and an overhead screen that displays an image of the tooth and how closely the student's drilling matches the target area. It's one of 20 simulators on which all University of Minnesota dental students will soon practice drilling, getting instant feedback not only on how accurately they're cutting--as dentists call it--but also on their all-important body position. The University's is the first dental school in the Big Ten, and one of only a handful nationwide, to acquire such technology. Instant feedback means more practice for students who will no longer have to wait for an instructor to come evaluate them. That kind of repetition is welcome in a field where sculpting a tooth must be precise to within a tenth of a millimeter.
Tour the lab
Take a virtual tour of the University of Minnesota School of Dentistry Simulation Clinic.
Not so easyThe technology rests on two sets of light-emitting diodes (LEDs). Seven LEDs beam from an immobile hook in the mannequin's mouth, and 16 others are arranged around the handpiece (drill). A computer keeps track of where the LEDs are in relation to each other and figures out the position of the handpiece and, thus, the drill head at the end of it. A trial run in one of the simulators generates an appreciation for the skills of a good dentist, as this intrepid reporter found out. It starts with donning latex gloves and holding the handpiece over a molar, then looking up at the screen to see a diagram of the tooth with an outline indicating the area to be drilled. So far so good. I step on the pedal and hear the hum of the drill but feel no vibrations to rock the steadiness of its touch. Gently applying the drill to the molar surface, I ... hold on, what's this water doing on the tooth? Oh. Cooling the drill, of course. But how can anybody see what they're doing through a puddle of water? So I do my best and then look up at the screen.
"A play-by-play on the screen that corrects your mistakes as you go is really great because then you don't get into bad habits."--Katie Daniels, dental student.Not bad. The computer has superimposed an outline of the area I drilled on the ideal and rated the job at 77, a passing grade. I drill a little more, trying to move the drill to trace the outline on the screen. My score rises to 80, a solid B-minus. "There are still some caries left. That's what those colored spots [on the tooth diagram] mean," Buchanan says. "You have to drill a little deeper." I go for it, stabbing here and there, trying to hit the exact places on the diagram. Suddenly, the resistance to the drill drops to nothing--and so does my grade. I've drilled too deep. Dentistry is even harder than it looks.