Products & safety
Interdental cleaning: floss, small brushes, water flossers and choosing a fit
On this page
Interdental means between teeth. Floss, small brushes and water flossers address spaces ordinary toothbrush bristles do not clean effectively. The device name, the shape of the space and the technique are separate considerations. A tool that fits one gap may not fit another.[1]
Different ways of reaching between teeth
| Term | Meaning | Boundary |
|---|---|---|
| Floss or tape | A strand passed along contacting tooth surfaces | Often used where a brush cannot fit[1] |
| Interdental brush | A small brush available in several sizes | Its size must match the particular gap[4] |
| Water flosser or oral irrigator | A purpose-made device delivering water between teeth | A separate device category; not an ordinary toothbrush[1] |
Size is part of the intervention
SDCEP guidance for diagnosed periodontitis recommends daily fitted interdental brushes where space permits, with floss for smaller spaces. The brush should fit snugly without its wire rubbing the tooth. Different gaps may need different sizes. For gingival inflammation without periodontitis, the method and frequency should be tailored. These are distinct populations; a disease-specific instruction should not silently become a personalized prescription for everyone.[4]
Restorations and crowded teeth can change the route
The European Federation of Periodontology highlights the difficulty of cleaning crowded teeth and areas around fillings, crowns or dentures. It recommends instruction adapted to the person and the spaces being cleaned. For example, a routine demonstrated on widely spaced front teeth may not transfer directly to a tight contact behind a crown. Ask the dental team to demonstrate the route on the actual area. The purpose is usable access and repeatable cleaning, rather than owning every kind of tool.[5]
Soft plaque and hardened tartar are different targets
ADA distinguishes bacterial plaque from tartar, a hard mineral deposit requiring professional removal. Home tools address debris and plaque before or between professional visits. A device that feels as though it has cleared food from a gap has not thereby removed all deposits or treated established periodontal disease. This distinction helps explain why a successful home routine and professional assessment can both be relevant.[1]
Evidence & uncertainty
UK guidance distinguishes daily prevention advice from limited trials measuring plaque and gum inflammation. Those outcomes do not establish an equally precise cavity-prevention benefit for every device.[3]
Selected-source overview · Independent review pendingPublished questions
Should every gap use the same interdental brush size?
Selected-source overview · Independent review pending. Read the evidence context.
Not necessarily. The brush should fit the particular space without its wire rubbing teeth, and several sizes may be needed. A dental professional can demonstrate the fit.[4]
Evidence behind this answer
- Oral hygiene aids
professional guidance · Date not stated
Official page text, relevant sections inspected · Toothbrushes, lines 8–47; Interdental cleaning, lines 50–82
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
What is the distinction between floss and a small interdental brush at a tight contact?
Selected-source overview · Independent review pending. Read the evidence context.
Floss is a strand that can address tight contacting surfaces; a brush needs enough space to fit. The appropriate route is determined by the gap, not simply by calling one device newer.[1]
Evidence behind this answer
- Dental Floss/Interdental Cleaners
professional guidance · Date not stated
Official page text, relevant sections inspected · Introduction; Other Interdental Cleaners; Evidence; Frequently Asked Questions, lines 34–68
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
Can a home water flosser or interdental brush remove hardened tartar?
Selected-source overview · Independent review pending. Read the evidence context.
Hardened tartar requires professional removal. Home cleaning tools address debris and plaque; they do not duplicate that procedure.[1]
Evidence behind this answer
- Dental Floss/Interdental Cleaners
professional guidance · Date not stated
Official page text, relevant sections inspected · Introduction; Other Interdental Cleaners; Evidence; Frequently Asked Questions, lines 34–68
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
Why may cleaning around a crown need a different technique?
Selected-source overview · Independent review pending. Read the evidence context.
Restorations and crowded teeth can make surfaces harder to reach. EFP recommends individualized instruction rather than assuming one demonstrated route fits every area.[5]
Evidence behind this answer
- Gum disease: Prevention
professional guidance · Date not stated
Official page text, relevant sections inspected · Oral hygiene at home, lines 33–43
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
Does less bleeding in a cohort prove one interdental device caused the improvement?
Selected-source overview · Independent review pending. Read the evidence context.
No. Cleaning and outcomes were self-reported and device allocation was not randomized. The study combined floss and other methods, so it cannot identify a superior device.[6]
Evidence behind this answer
- Interdental Cleaning and Oral Health Status in an Adult Cohort, 2015 to 2018
original human research · 2020
Original abstract plus selected full-text Methods/Discussion inspected · Abstract lines 77–83; Methods; Discussion lines 360–372
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
Do the reviewed interdental trials directly establish a quantified cavity benefit?
Selected-source overview · Independent review pending. Read the evidence context.
No. The toolkit notes that the trials largely measured plaque or gum inflammation rather than caries. Those endpoints leave the precise long-term cavity question unanswered.[3]
Evidence behind this answer
- Chapter 8: oral hygiene
agency guidance · Date not stated
Official page text, relevant sections inspected · Powered versus manual toothbrushes; Interdental cleaning; Oral hygiene advice
This answer summarizes selected sources. An independent appraisal of the complete evidence has not been completed.
What randomized device trials actually measured
The 2019 Cochrane review included thirty-five studies and 3,929 adults. Evidence for short-term gingivitis or plaque benefits was low or very low certainty. No included trial measured decay, and few assessed severe gum disease. Limited, inconsistent irrigator findings cannot establish universal superiority of a water flosser over floss or brushes.[2]
A large cohort found an association with less reported bleeding
A US PATH cohort study analyzed 26,086 adults at baseline and 22,585 at follow-up. Cleaning at least seven times a week, compared with none, was associated with less reported gum bleeding in the following twelve months: adjusted odds ratio 0.62, with a 95% confidence interval of 0.54 to 0.70. Several more advanced oral-health outcomes were not significantly lower. The participants reported both cleaning and outcomes themselves. Device choice was not randomized, and the cleaning question combined floss with other devices, so the result does not rank individual tools.[6]
Order advice is often about establishing a workable habit
EFP’s patient guidance suggests interdental cleaning before toothbrushing. It also emphasizes choosing tools to fit gaps and obtaining instruction. An order recommendation can organize a repeatable routine; it does not mean a missed sequence proves the teeth were harmed. The useful comparison is whether the person can clean the intended surfaces consistently with the chosen method. This page does not select a pressure setting for an irrigator, a particular brush diameter or a treatment for persistent bleeding.[5]
The unanswered outcome should stay visible
The UK toolkit says the trials focus mainly on plaque and gingivitis, rather than caries. The cavity benefit therefore remains undetermined, which differs from demonstrating no benefit.[3]
References
- Dental Floss/Interdental Cleaners
Professional guidance
American Dental Association · Content/publication date: not stated
Accessed: 2026-10-13 UTC · Official page text, relevant sections inspected
Cited sections: Introduction; Other Interdental Cleaners; Evidence; Frequently Asked Questions, lines 34–68Guidance is broader than trial evidence. Do not claim home flossing has a quantified cavity-prevention effect.
- Home use of interdental cleaning devices in addition to toothbrushing
Original systematic review
Worthington et al.; Cochrane · Content/publication date: 2019
Accessed: 2026-10-13 UTC · Original review summary and abstract inspected
Cited sections: Study characteristics; Key results; Certainty of the evidence, lines 48–76Reuse budget only63 words; reserve ≤60 for one compact review paragraph. Do not switch representations to evade original-source budget.
- Chapter 8: oral hygiene
Agency guidance
UK Office for Health Improvement and Disparities · Content/publication date: not stated
Accessed: 2026-10-13 UTC · Official page text, relevant sections inspected
Cited sections: Powered versus manual toothbrushes; Interdental cleaning; Oral hygiene adviceGuidance summarizes reviews; its cited trial populations and endpoints do not support ranking current retail devices. UK guidance commonly recommends medium texture, whereas ADA recommends soft.
- Oral hygiene aids
Professional guidance
Scottish Dental Clinical Effectiveness Programme · Content/publication date: not stated
Accessed: 2026-10-13 UTC · Official page text, relevant sections inspected
Cited sections: Toothbrushes, lines 8–47; Interdental cleaning, lines 50–82Different recommendation populations must remain explicit. SDCEP recommends medium texture rather than universal soft bristles.
- Gum disease: Prevention
Professional guidance
European Federation of Periodontology · Content/publication date: not stated
Accessed: 2026-10-13 UTC · Official page text, relevant sections inspected
Cited sections: Oral hygiene at home, lines 33–43Patient guidance; do not generalize its mouthwash advice to all readers.
- Interdental Cleaning and Oral Health Status in an Adult Cohort, 2015 to 2018
Original human research
Chaffee, Persai and Vora · Content/publication date: 2020
Accessed: 2026-10-13 UTC · Original abstract plus selected full-text Methods/Discussion inspected
Cited sections: Abstract lines 77–83; Methods; Discussion lines 360–372Self-report, approximately one-year outcome period, self-selection/confounding; not a device ranking.
Scope & review
- Population
- General readers considering dental care; study-specific populations and ages identified
- Exposure or intervention
- Interdental cleaning
- Comparison
- Floss/tape, fitted interdental brushes and oral irrigators as additions to brushing; short-term indices separated from advanced disease outcomes
- Outcomes
- Definitions, practical distinctions, source-specific clinical outcomes and uncertainty
- Timeframe
- Selected historical and current evidence checked 2026-10-13
- Jurisdiction
- Selected US agency sources, dated professional guidance and original international research; jurisdiction and eligibility are source-specific
Bounded selected-source educational explanation distinguishing official guidance, original research and editorial interpretation. No exhaustive search, independent systematic synthesis or qualified dental review has been completed.
Sources checked on their individual access dates. Selected sources were checked; ongoing surveillance and qualified review have separate statuses on the coverage page.
Revision history
- 2026-10-13 UTC: Added a definition-first dental explanation; qualified independent review remains pending.
What this article still leaves open
- Which gap sizes and techniques suit the person’s teeth, restorations, dexterity and periodontal condition?
- Modern irrigator comparisons, long-term caries and tooth-retention outcomes and qualified review remain incomplete.
Suggest a correction
Submit a content correction to the editorial queue, or download a local note. Leave out personal medical details. Submitted text is stored privately with a browser receipt session and is visible to this browser and the editor. Clearing cookies removes access to your submission history. This is not an account or a medical service.
Your submitted corrections for this article
Explore the topic map
Browse the health domains connected to this article. The map also identifies topics whose articles remain unwritten.