1. Data on File at Align Technology as of July 2021. Based on survey data of doctors in USA and Canada who have used Vivera™ retainers (n = 253), who were asked to answer the question, “How would you rate your overall satisfaction with the following retainers?” on a 5 point scale: Don’t know, very dissatisfied, dissatisfied, satisfied, very satisfied. “Don’t know” responses were excluded from analysis.