What combination produced the high-speed handpiece era as the third dental golden age? Three changes that arrived nearly simultaneously and reinforced each other into a leap in productivity. The first was four-handed dentistry, the workflow innovation that brought a dental assistant into active partnership with the doctor at the chair, dramatically reducing wasted motion and dropped instruments. The second was the redesign of dental chair construction to support seated dentistry, which let the doctor work in an ergonomic posture instead of standing for hours and ended a major source of career-shortening physical strain. The third was the high-speed handpiece itself, which [...]