The vision of the use of clear aligners for comprehensive orthodontic treatment first began in 1945. In 1999, Align Technology pioneered the invisible orthodontic market with the introduction of the Invisalign System. By 2001, 1 million clear aligners had been manufactured. By combining digital treatment planning, including 3D technology, and mass-customisation, the orthodontic industry has been transformed. As of January 2015, over 4 million patients have started Invisalign treatment.