1. David W. White, Katie C. Julien, Helder Jacob, Phillip M. Campbell and Peter H. Buschang, Discomfort associated with Invisalign and traditional brackets: A randomized, prospective trial. The Angle Orthodontist Nov 2017, Vol. 87, No. 6 pp. 801-808
2. Some doctors still take physical impressions using a soft putty. These impressions are then scanned by Invisalign technicians to create the 3D image for use in the ClinCheck® software and manufacturing aligners.