Writing for The Atlantic, Zoë Schlanger observes that we welcome plastic intentionally, and sometimes permanently, directly in our mouths when we go about our oral care. She notes that a letter published in a dental journal last year by Adith Venugopal, an orthodontist and a senior lecturer in the Faculty of Dentistry at the University of Otago, New Zealand, raising concerns about the micro- and nanoplastics that slough off aligners and retainers, is just one in a growing body of statements and studies coming out of the profession that ask if plastic may be harming patients. The chief scientific officer of the American Dental Association’s research unit, Ben Wu, said the association is “closely monitoring the scientific literature on microplastics,” but that “no clinical evidence currently exists showing a meaningful oral or overall health impact from the particles.”