Our Patients Ask: Should I Brush or Floss First?

“Should I brush or floss first?” It's a question our team hears almost every week. Some patients have heard brushing should come first so that fluoride can coat every surface. Others have read that flossing first loosens debris so brushing can sweep it away. The truth? Both arguments have merit — and dental professionals themselves don't always agree.

At Orion Dental in Scarborough and Milton, we believe the priority is doing both consistently and thoroughly. That said, there is growing evidence that one order may offer a slight edge. Let's break it down.

The Case for Flossing First

A 2018 study published in the Journal of Periodontology found that participants who flossed before brushing had significantly less plaque between their teeth compared to those who brushed first. The reasoning is straightforward: flossing dislodges food particles and breaks up the sticky bacterial film between teeth. When you brush immediately afterward, the fluoride in your toothpaste can reach those freshly cleaned interdental surfaces more effectively.

Think of it like sweeping a floor before mopping. Removing the larger debris first allows the cleaning solution — in this case, fluoride toothpaste — to make better contact with the surfaces that need it most. This approach may also help rinse away the loosened plaque and particles during the brushing step, rather than leaving them trapped between teeth.

The Case for Brushing First

The brushing-first camp makes a practical argument: when you brush first with fluoride toothpaste, you coat your teeth in a protective layer. Flossing afterward distributes some of that fluoride into the spaces between teeth — areas the toothbrush bristles can't easily reach.

There's also a behavioural component. Many people find it easier to start with the habit they find less tedious — brushing — and then move to flossing while they're already in “cleaning mode.” If brushing first makes you more likely to floss at all, that alone is a significant benefit for your oral health.

Some dental professionals also point out that brushing first removes the bulk of plaque and food from tooth surfaces, making it easier to see and feel where floss needs to do its work. This can be particularly helpful for patients who are still developing their flossing technique.

Floss First vs. Brush First: A Quick Comparison

Here's a side-by-side look at the arguments for each approach:

What Matters More Than the Order

Regardless of which step comes first, the quality of your technique and the consistency of your routine have the greatest impact on your oral health. The Canadian Dental Association emphasises that the sequence is less important than doing both thoroughly every single day.

If you find traditional string floss difficult to use, ask your dental team about alternatives. Water flossers, interdental brushes, and floss picks can all be effective, though some work better for specific situations. During your next comprehensive checkup, we can recommend the tool that suits your mouth and dexterity.

Getting the Technique Right

Even with the right order, poor technique limits your results. Here is a refresher on how to get the most from each step:

Brushing Technique

Hold your brush at a 45-degree angleto the gum line. Use gentle, circular or short back-and-forth strokes — never scrub aggressively, as this can wear down enamel and irritate gums. Spend roughly 30 seconds on each quadrant of your mouth (upper right, upper left, lower right, lower left). Don't neglect the inner surfaces of your teeth, which tend to accumulate more plaque than the outer surfaces.

Flossing Technique

Use approximately 45 cm (18 inches) of floss, winding most of it around your middle fingers. Guide the floss gently between teeth using a back-and-forth motion — never snap it down into the gums. Curve the floss into a C-shape around each tooth and slide it beneath the gum line. Use a fresh section of floss for each tooth. For a detailed walkthrough, see our guide on how to floss your teeth properly.

Common Mistakes That Undermine Your Routine

Even patients with consistent habits sometimes make errors that reduce the effectiveness of their care. Watch out for these common pitfalls:

If you experience persistent bleeding gums, sensitivity, or bad breath despite a consistent routine, it may indicate early gum disease or another dental concern. A professional evaluation can identify the cause and guide your next steps.

Beyond Brushing and Flossing

A strong home care routine is your first line of defence, but it works hand in hand with professional care. Even with excellent brushing and flossing, tartar (calculus) builds up in areas that are difficult to reach at home. Regular dental cleanings remove this buildup and give your dental team the opportunity to check for early signs of decay, gum disease, and other concerns.

Diet also plays a significant role. Frequent snacking on sugary or acidic foods creates an environment where cavity-causing bacteria thrive. Drinking water throughout the day — especially after meals — helps rinse away food particles and maintain a healthy pH in your mouth. If you're prone to cavities, your dentist may recommend dental sealants as an additional protective measure.

Our Recommendation

Based on the available evidence, our team generally suggests flossing before brushing— but we emphasise that doing both thoroughly matters far more than the order. Choose whichever sequence you're most likely to stick with every day. Consistency is the single greatest predictor of long-term oral health.

Have more questions about your home care routine? Bring them to your next visit at our Scarborough or Milton office. Book an appointment or call 416-291-0306 (Scarborough) / 905-636-9770 (Milton).