Resolving to maintain better oral health in the new year? Break these bad brushing habits in 2019! Here is a summary of some of the advice: How old is your toothbrush? It should be replaced every 3 to 4 months, according to the ADA consumer website, MouthHealthy.org. When a brush's bristles appear to be frayed and broken — that's a good sign it's time to replace it, preferably with a toothbrush that has earned the ADA Seal of Acceptance. Most people brush their teeth for 45 s