Yes, flossing is necessary. The NHS recommends that everyone over the age of 12 uses dental floss or interdental brushes as part of their daily oral hygiene routine. Flossing reaches the 35% to 40% of tooth surfaces that a toothbrush cannot access, removing food particles and plaque from between teeth and below the gum line.
The debate around flossing tends to stem from a misunderstanding of the evidence. While large-scale clinical trials on flossing alone are limited, smaller studies consistently show that people who floss regularly have less plaque buildup, less bleeding of the gums and a lower incidence of mild gum disease. No dental professional would advise against it.
Brushing cleans the front, back and biting surfaces of your teeth. It does not clean between them. The gaps between teeth are where plaque accumulates most easily and where bacteria thrive undisturbed if nothing is done to remove them.
When plaque is left between teeth, it produces acids that erode enamel and irritate gum tissue. Over time, this leads to:
| Consequence | What Happens |
|---|---|
| **Interproximal cavities** | Decay forms between teeth, often invisible until it reaches an advanced stage |
| **Gingivitis** | The early stage of gum disease, characterised by red, swollen or bleeding gums |
| **Bad breath** | Trapped food particles decompose and produce volatile sulphur compounds |
| **Periodontitis** | If gingivitis is not addressed, it can progress to periodontitis, causing bone loss and potentially tooth loss |
Flossing is not a replacement for brushing. It is a complement to it. Together, brushing and flossing cover all accessible tooth surfaces and significantly reduce the conditions that lead to decay and learn more gum disease.
Many people avoid flossing because they find it uncomfortable or are unsure of the correct technique. Incorrect flossing can indeed cause gum bleeding and discomfort, which reinforces the idea that it is harmful. In reality, the issue is technique, not the practice itself.
1. Cut approximately 45 cm of floss. Wind most of it around the middle finger of one hand and a small amount around the middle finger of the other hand. This gives you a clean section of floss for each gap.
2. Hold the floss taut. Grip it between your thumbs and index fingers, leaving about 2 to 3 cm of floss between your hands.
3. Guide the floss gently between your teeth. Use a gentle rocking motion to ease the floss into the gap. Do not snap it down onto the gum, as this causes injury and bleeding.
4. Curve the floss into a C-shape against one tooth and slide it gently up and down, going slightly below the gum line. Repeat against the adjacent tooth.
5. Use a clean section of floss for each gap as you work your way through your mouth.
6. Work methodically. Start from one side of your mouth and move systematically to the other, so you do not miss any gaps.
| Feature | Dental Floss | Interdental Brushes |
|---|---|---|
| **Best for** | Tight gaps between teeth | Wider gaps or spaces around bridgework |
| **Ease of use** | Requires manual dexterity | Easier for most people to handle |
| **Effectiveness** | Effective when used correctly | Slightly more effective at reducing plaque in wider gaps |
| **Recommendation** | Standard recommendation for most adults | Preferred by many dentists and hygienists for accessibility |
If you find flossing difficult, interdental brushes are a highly effective alternative. Your dentist or hygienist at Pure Smiles can recommend the correct size for the gaps between your teeth.
Being too aggressive. Snapping floss into your gums causes bleeding and soreness. A gentle rocking motion is all that is needed to guide floss between teeth.
Only flossing when food is stuck. Flossing is not just for removing visible food debris. Its primary purpose is to disrupt the invisible plaque biofilm that forms between teeth daily.
Giving up when gums bleed. If your gums bleed when you start flossing, this is usually a sign of inflammation caused by existing plaque buildup. Continued gentle flossing will reduce the inflammation, and the bleeding should stop within one to two weeks. If it persists, see your dentist.
Reusing the same section of floss. Each gap should be cleaned with a fresh section to avoid transferring bacteria from one area to another.
Floss at least once a day. Whether you floss in the morning or evening does not matter, as long as you do it consistently. Many people find it easiest to floss before bed, after their final meal of the day, to ensure their teeth are clean overnight when saliva production drops.
Flossing is one component of a complete daily routine that should also include:
If you are unsure about your flossing technique or want personalised guidance on your oral hygiene routine, our dental hygienists can help. At Pure Smiles, we take time to demonstrate proper technique and recommend the right tools for your teeth.
Dr Ayzaaz Akram (BDS University of Liverpool 1995, GDC 70996) leads our family-run practice across two Fulham locations:
To book an appointment, call us on 020 7736 6276 or learn more contact us online.
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Yes. Brushing only cleans about 60% to 65% of your tooth surfaces. The remaining surfaces, between your teeth and just below the gum line, can only be reached by floss or interdental brushes. Without cleaning these areas, plaque builds up and increases your risk of cavities and gum disease.
Bleeding gums during flossing are usually a sign of gingivitis, the early stage of gum disease caused by plaque buildup. Gentle, consistent flossing removes the plaque causing the inflammation, and the bleeding typically stops within one to two weeks. If bleeding continues beyond this, see your dentist for assessment.
Both are effective. Interdental brushes are often easier to use and may be slightly more effective in wider gaps. Traditional floss works well for tight spaces. Your dentist or hygienist can recommend the best option based on the spacing of your teeth. Many people benefit from using both.
Yes. The NHS recommends flossing from around age 12, when children have the manual dexterity to do it safely. For younger children, parents can help with flossing, particularly if teeth are tightly spaced and prone to trapping food. Speak to your dentist about when to introduce flossing for your child.
There is no clinically superior time to floss. The most important factor is consistency. Many dental professionals suggest flossing before bedtime, as this removes the day’s accumulated plaque and food particles before the overnight period when saliva production naturally decreases.
