In 1949 NZ dentist John Patrick Walsh (b. 1911, d. 2003) worked with lab staff in Wellington and created a drilling handpiece that was driven by compressed air. The air is forced pneumatically through to the handpiece where the speed of the air passes over fins inside the drill to spin the handpiece at a tremendous rate. This new handpiece was so well-designed that it remains virtually unchanged and universally adopted today.
Walsh's drills typically spin at 400,000 revolutions per minute (rpm), versus the precious low speed drills which operated at about 3,000 rpm. That extra speed translates to quicker drilling, and less patient discomfort. While he was born in Australia, Walsh (later knighted for his services to dentistry - I wonder if he got a plaque? Sorry...) adopted New Zealand as his home, and made a number of contributions to Dunedin, where he based himself and helped establish the University of Otago's school of dentistry.
He also changed the way that dentists worked with their patients, seeming them as people who needed holistic treatment, not just a set of mandibles and canines.