Americans are told to see the dentist twice a year, and the next cleaning is usually booked before the patient leaves. Insurance plans commonly pay for two cleanings a year.
Where the rule came from is uncertain. One account traces it to an old Pepsodent toothpaste slogan: “Use Pepsodent every day – see your dentist twice a year.” A Cochrane review in 2013 found “no evidence to support or refute” the practice.