Why Does My Floss Smell Bad?


We’ve all had that moment where today is going to be the day. We’re finally going to heed the words of our dentist and start flossing. This is usually predicated by a dental visit where we were calmly informed that in addition to improved tooth brushing we should seriously consider dental floss.

So, today being a new day, we include this action into our daily routine. However, when  performing this seemingly benign task, we discover an offensive odor, that is slightly analogous to West Texas road kill. So, what’s going on here, and is this normal? Well it’s not normal, but it is very common. Professionally speaking, there’s not a person on the planet who hasn’t experienced this unfragrant bouquet at some point in their lives. And yes, it causes bad breath, so please read on.

If the floss smells bad, it means that food particles, usually meat, or some other type of fibrous organic is getting trapped in the space between the teeth. It’s been allowed to sit in this space for 24 plus hours, and is basically rotting. What you are smelling on your floss is a sulfur gas produced by this rotting process.

There are multiple conditions that can cause this but the most common is what we in the dental community call an “open contact”. An open contact is when the teeth do not touch one another tightly. You have an open contact if the floss slides between the teeth without an audible click or pop; It just goes in without any resistance at all. Know that each time you eat, food will get packed into this area. However,poor and inadequate brushing can also cause this odeur;  open contacts just make it easier.

OK, so now you know why the floss reeks like a bait bucket in mid-July, but what can you do about it, right? Well, plain and simply you must floss…DAILY.  Yes, I know flossing sucks, but think of it as breath control. Think about how many more deals you’re going to close when your breath is not mandating a federally funded quarantine zone. Think about the confidence that comes from knowing that your breath is inviting, as opposed to repelling.


To eliminate bad breath and prevent the onset of gingivitis, perform this routine at night just before bed.

  • Brush your teeth. Know that there is a right way and a wrong way to brush. If you are brushing your teeth the same way you did back in the third grade ( up and down or circles) you need to change. Additionally, if your gums bleed when you brush or floss you need to change.  HOW you brush is critical.  I recommend the MD Brush . It’s the most expensive manual toothbrush on the market, but once you use it you’ll understand why. Do not brush in circles or up and down unless you have been advised to do so by your dentist.
  • Floss. Remember you are trying to scrape the goop off the sides of the teeth, so make sure to pull and push against the teeth as you slide the floss down in-between. Simply popping the floss in- between, and then back out again. is not sufficient. Floss and repeat until the floss doesn’t stink.
  • Brush again (Bass Method), but this time instead of using toothpaste, use Listerine mouthwash. You will be brushing with a liquid so it will be running down your arm and making a mess. NOTE: DO NOT RINSE THE LISTERINE OUT, just let it linger. It will continue to kill bacteria for up to 5 hours provided you don’t rinse or drink anything Preforming your home oral care like this will yield immediate results. But remember, the bacteria in your mouth will never take a vacation, call in sick, or quit.  All they do is grow, multiply, and release toxins, so your floss can return to a  stinky state within 24 hours.

Written By, Mike Davidson – Maverick Dental Hygienist and CEO