FLOSS BEFORE OR AFTER BRUSHING

I have been a dentist since 2007. For years I have told my patients that it doesn’t matter whether you floss before or after brushing your teeth. The order was not necessary as long as you did both. If you ask any dental professional, they will answer to the best of their knowledge, but most dentists have never looked at the topic thoroughly. However, now I have a clear favorite for which sequence cleans better, and in this article, I will show you why this is important.

Benefits of Flossing Before Brushing

Removes More Plaque Between Teeth

Unremoved Plaque Won't Block Fluoride

Floss Loosens Plaque Then Brush It Away

Unfragmented Plaque Colonies Dislodge More Easily

Should You Brush Before Flossing Your Teeth?

On two separate days after not brushing for twenty-four hours, I disclosed all the plaque in my mouth with pink plaque-staining tablets so that we could visualize the results. You can see my plaque levels on the first day before I brush in the images following this section. To clean my teeth on this day, I brushed my teeth first, and then after that, I flossed my teeth. I used the brushing technique recommended by toothbrush companies to guide the brush along with the teeth and let the brush’s sonic movements do all the cleaning. Watch the video above to see the same technique I used on both days. Now take a look at the following image to see results after brushing. If you look closely, you can see that the brush did a good job brushing the anterior teeth, but it misses some of the spots on the posterior teeth. When I brush, letting the toothbrush do all the work, you can see that it left some plaque behind, mainly on the surfaces between my teeth. In general, the missed plaque between my teeth is why flossing is so important. Now, this is my favorite floss, and there isn’t another floss that even comes close because it is so good at removing plaque.

From the following images, you can see the results are pretty good. There is a little bit of plaque left behind here and there, but overall it did a good job. However, you should not brush before flossing because it would break up plaque colonies before flossing, remove less plaque, inhibit toothpaste flowing between teeth, block toothpaste from interacting with plaque-covered teeth, and leave dislodged plaque in the mouth.

BEFORE Brush then Floss Should you Floss Before or After Brushing

Plaque amount before brushing then flossing.

After Brushing Before Flossing Should you Floss Before or After Brushing

Plaque amount after brushing but before flossing.

After Brush Then Floss Should you Floss Before or After Brushing

Plaque amount after brushing then flossing.

Should You Floss Before Brushing Your Teeth?

Next, let's move on to flossing then brushing. So I start once again with my favorite floss. If you watch my video, you can see how this floss flattens against the plaque and pushes the plaque colony around, especially when I floss first. Dislodging dental plaque is good because you have to disrupt plaque once every 24 hours to stop cavities. If you compare flossing on both days, the floss bulldozes its way through the plaque when flossing first. When I brush first, the floss moves around fragmented pieces of the plaque colony. After the floss, I move on to brushing. After 2 minutes of brushing with the same technique as day one, let's look at the results. Now, these results are excellent and almost spotless. If you nitpick, you can see little spots missed, but those are primarily because of the poor brushing technique I used just for this experiment. Watch or read my article on the best brushing technique if you want to know more about that. The impressive part is that there is no pink plaque remaining between the teeth. I even spot-check my results with white floss, and it is all clear of pink plaque.

You should floss before brushing because it will not break up plaque colonies before flossing, remove more plaque, propel more toothpaste between teeth, allow toothpaste to interact more fully with teeth, and brush away plaque only dislodged by floss.

BEFORE Floss then Brush Should you Floss Before or After Brushing

Plaque amount before flossing then brushing.

After Flossing Before Brush Should you Floss Before or After Brushing

Plaque amount after flossing but before brushing.

After Floss then Brush Should you Floss Before or After Brushing

Plaque amount after flossing then brushing.

Why Flossing Before Brushing Is Better

So now, let's look at the results of both days side by side. I have repeated this many times, and I think we can definitively say that flossing then brushing gets way better results than brushing and then flossing. Let's talk about why? After thinking about it more in-depth, there are a lot of reasons. When cleaning your teeth, it is the floss that does most of the work to knock the plaque loose in between your teeth. The toothbrush isn’t near as effective at cleaning plaque further between your teeth.

As you can see from day two, the floss will move the whole colony of plaque almost as one attached unit. Because the plaque colony is all attached, the floss doesn’t necessarily have to contact all of the plaque to move it. Then the brush's job is much easier to do the detailed clean-up work if any plaque remains. When you brush first, it breaks up and detaches the plaque colony from each other between your teeth, which fragments the plaque colony, making it impossible for the floss to do the heavy lifting of the whole colony as one complete unit. When flossing second, the floss must contact each tiny leftover plaque fragment and cannot heavily remove plaque between the teeth. As an analogy, if you were redoing your yard, you wouldn’t use a plow truck to dig holes for the plants, nor would you use a shovel to plow the whole yard. Floss is the plow truck when it comes to plaque between the teeth.

You may not know this, but electric toothbrushes propel the saliva-and-toothpaste mixture through the small gaps between the teeth. As saliva with toothpaste moves between your teeth, it does two things only if you have flossed before you brush your teeth. First, the actual flow of toothpaste from a mechanical toothbrush is enough to remove some of the debris itself. Second, toothpaste typically has fluoride that strengthens tooth enamel. However, if plaque is still sitting in between your teeth, it will block the toothpaste fluoride from strengthening that part of the tooth. Thus fluoridated toothpaste does not fortify between your teeth near as much if you brush first.

Plaque amount after brushing then flossing.

Plaque amount after flossing then brushing.

AFTER FLOSS THEN BRUSH WITH GOOD TECHNIQUE AND TOOTHBRUSH

Plaque amount after flossing then brushing with a good brush technique and great toothbrush.
(See our video or article on the best daily brushing and flossing routine.)