Coffee is one of the reasons that cause bad breath, so you should consider reducing that habit. The teeth fillings usually cannot be related with the bad breath, so the main reason here for you is coffee, but it isn’t limited to it.

Bad breath has many other causes too, like the improper oral hygiene, tongue cleaning, and also systemic reasons. Are you having any problems with your stomach? You should once visit a doctor and get it checked whether you are suffering from any condition like GERD etc.

First of all, you need to keep a control on the diet and the food you eat. Onions are one of the usually eaten stuff, and which cause an unpleasant odor. You should brush twice daily with a proper toothbrushing technique, and along with it, you need to use a tongue cleaner to keep the tongue rid of food debris.

Use a mint-flavored mouthwash for a couple weeks after you brush, which freshens the breath for a few hours. Flossing as you are doing should be continued. It will be helpful ultimately when you are doing the other practices well.

Dr. Chetan