It helps to know what causes bad breath. While halitosis, the medical term for bad breath, is often the result of bacteria build-up from food particles, there are other causes including medical conditions, dry mouth, and digestive problems. The most effective way to counter bad breath is to maintain good oral care habits, and to use dentist-recommended fresh breath products. Make sure you brush your teeth twice a day, and floss once a day. Change your toothbrush after 3 months or when its bristles show signs of wear. An electric toothbrush is a great way to effectively clean your teeth as well (though if your gums or oral tissue are sensitive, you may want to consider using a Post-Surgery Bamboo Charcoal Toothbrush).