Interdental cleaning is an indispensable part of oral hygiene, removing the harmful bacterial plaque that a toothbrush cannot reach between teeth. Failing to clean these surfaces can lead to gum inflammation and disease. While dental floss was the standard tool, the interdental brush (IDB) has gained attention as a mechanical alternative. Both tools aim to disrupt the sticky biofilm between teeth, but they achieve this goal through fundamentally different designs.
How Interdental Brushes and Floss Work
Dental floss is a thin filament or tape maneuvered between adjacent teeth. Its primary action is a scraping motion, relying on friction to shear the plaque biofilm off the tooth surface. Effective use requires considerable manual dexterity, as the user must wrap the floss into a “C” shape around each tooth and move it beneath the gumline.
Interdental brushes (IDBs) operate on a mechanical scrubbing principle, similar to a miniature toothbrush. These tools feature small bristles wrapped around a thin wire core and come in numerous diameters to match the specific size of the gap between teeth. When inserted, the bristles fill the area and physically scrub multiple surfaces simultaneously, disrupting the plaque with a simple back-and-forth motion.
Clinical Evidence Comparing Cleaning Efficacy
Scientific consensus suggests that interdental brushes are generally more effective than floss for plaque removal and gingivitis reduction, provided the interdental space allows for proper fit. For spaces large enough to accommodate an IDB, the brush’s full circumference of bristles covers a greater surface area than a single strand of floss. This increased contact translates to a more thorough mechanical disruption of the plaque biofilm, leading to greater reduction in plaque scores and bleeding indices in clinical trials. For patients experiencing moderate to severe periodontitis, IDBs have demonstrated superior results in reducing probing depth compared to floss. However, this clinical superiority is entirely dependent on the anatomy of the mouth; floss remains the only option for individuals with extremely tight contact points between teeth.
Choosing the Right Tool for Your Mouth
When to Use IDBs
The most appropriate tool for interdental cleaning is highly individualized, depending largely on the physical spacing between the teeth and the user’s ability to handle the device. If a space is wide enough to insert an interdental brush without forcing it, the IDB is the preferred tool because of its demonstrated cleaning superiority. This often applies to areas with gum recession or existing periodontal issues that have created larger gaps.
When to Use Floss and Special Considerations
For teeth with very tight contacts, dental floss is necessary because an IDB cannot be inserted without causing trauma to the gum tissue. IDBs are also easier to use for people with limited hand mobility, such as those with arthritis, since they require less fine motor control than manipulating string floss. Furthermore, IDBs are essential for cleaning around complex dental work, such as fixed bridges, implants, or orthodontic appliances. Ultimately, consistency and correct technique are the most important factors, and consulting with a dental professional is the best way to determine the correct size of IDB for each specific space.