Brushing cleans only about three of the five surfaces of each tooth. The two surfaces between teeth, where decay and gum disease most often start, need a separate tool. The trouble is that around three in four people rarely or never clean between their teeth. The best tool is genuinely the one you will use every day, and the three main options, string floss, interdental brushes, and water flossers, each have a place.
Key takeaways
- Cleaning between teeth daily matters as much as brushing for preventing gum disease.
- Interdental brushes are highly effective where the gaps are large enough to fit them.
- Water flossers are at least as good as string floss for most people, and easier for many.
- String floss is cheap, portable, and works well for tight contacts.
- The best tool is the one you will actually use consistently.
The one rule: doing it daily beats the perfect tool
Dentists argue about which tool is best, but the evidence is clear that any daily between-teeth cleaning beats none. If you have tried string floss for years and never stuck with it, switching to a water flosser or interdental brushes that you will use every day is a clear win. Do not let the search for the perfect method stop you doing something consistently. Consistency is the whole game.
The three options compared
String floss
The classic. A thin thread cleans the contact point and just below the gumline between two teeth. It is inexpensive, portable, and excellent for tight contacts where nothing else fits. The downsides are that it takes some dexterity, many people find it fiddly, and poor technique can miss the spot or nick the gums.
Interdental brushes
Small bristled brushes, a bit like tiny bottle brushes, that come in various sizes to fit between teeth. Where the gaps are big enough, the evidence rates them very highly, often ahead of string floss, because they physically scrub the surfaces and reach into concave areas. They are the go-to for larger spaces, exposed roots, and many people with gum disease. The key is choosing the right size, which your dentist or hygienist can help with.
Water flossers
A water flosser, or oral irrigator, sends a targeted stream of water between the teeth and along the gumline. Reviews of the research find water flossers are at least as effective as string floss at reducing plaque for most people, and they have an edge in places string floss struggles to reach, such as around braces, bridges, and implants, and in deeper gum pockets. They are easier for people with limited dexterity or arthritis. The downsides are the upfront cost, the bench space, and that some people find them messy at first.
At a glance
| Tool | Best for | Strengths | Limitations |
|---|---|---|---|
| String floss | Tight contacts, travel, tight budget | Cheap, portable, effective with good technique | Fiddly, technique-sensitive |
| Interdental brushes | Larger gaps, gum disease, exposed roots | Very effective scrubbing, easy to use | Need the right size, do not fit very tight gaps |
| Water flosser | Braces, bridges, implants, limited dexterity | Easy, reaches awkward areas and pockets | Cost, bench space, can be messy |
Which should you choose?
There is no single winner, only the best fit for your mouth and habits.
- If your teeth are tight together, string floss or a fine interdental brush reaches the contact best.
- If you have larger gaps or gum disease, interdental brushes of the right size are often the most effective choice.
- If you have braces, a bridge, or implants, a water flosser cleans around the hardware far more easily.
- If dexterity is a challenge, a water flosser or interdental brushes on a handle are kinder on the hands.
- If you have never stuck with flossing, try a water flosser; many people find it the first method they keep up.
Plenty of people use a combination, for example interdental brushes for the bigger gaps and floss for the tight front teeth. Your dentist or hygienist can tailor a routine to your mouth.
How this fits with the rest of your routine
Cleaning between teeth works alongside, not instead of, brushing twice a day with fluoride toothpaste. For brushing technique, see our guide on how to brush properly, and for flossing technique, our guide on how to floss. Cleaning between teeth is one of the most effective things you can do to prevent the bleeding gums that signal early gum disease, covered in our article on bleeding gums.
Common questions
Is a water flosser better than string floss?
For most people it is at least as effective at reducing plaque, and it is easier to use and better around braces, bridges, and implants. String floss still has the edge for very tight contacts and for portability.
Can a water flosser replace flossing?
For many people, yes, it can be their main between-teeth tool. The important thing is that you clean between your teeth daily by some method. If a water flosser is what you will use, it is a good choice.
Are interdental brushes better than floss?
Where the gaps are big enough to fit them, the evidence often rates interdental brushes ahead of string floss. For very tight teeth, floss reaches where a brush cannot.
Do I still need to brush if I use a water flosser?
Yes. Brushing and between-teeth cleaning do different jobs. A water flosser cleans between teeth and along the gumline but does not replace brushing the tooth surfaces.
Which is best if I have braces?
A water flosser is usually the easiest and most effective option around braces, as it flushes food and plaque from around the brackets and wires where string floss is awkward. Interdental brushes also help.
The takeaway
String floss, interdental brushes, and water flossers all clean between the teeth well when used properly. Interdental brushes shine in larger gaps, water flossers suit braces, bridges, implants, and tricky dexterity, and string floss is the cheap, portable standby for tight contacts. The best one is simply the one you will use every day, so pick the tool that fits your mouth and your routine and stick with it.
If you would like help choosing and sizing the right tools for your mouth, the team at Lumi Dental in Melrose Park is happy to guide you. Get in touch, see our general dental care, or view current offers on our deals page.
