Any mask will make you more aware of your breath. The more highly filtering kinds like N95s or even surgical masks that seal more tightly will give you an idea of how your mouth is doing. I’ve been wearing a mask for years, so I know.
If your oral hygiene has been lacking during COVID-19, you may be noticing some not-great smells under your mask. It’s an excellent reminder to get into your dentist for a cleaning.
Drinking more water can help with bad breath. The dryer our mouth is, the less odor-causing bacteria are being washed away. Water can help with this.
Also, have you checked your tongue lately? Tongues should be pink and look clean. If your tongue looks white or even brown, it’s time to get a tongue scraper. Much odor-causing bacteria collects on the tongue. And, of course, the tried and true flossing and brushing for two minutes twice a day!