Interdental brushes (IDBs) are specialized oral hygiene tools designed to clean the surfaces of your teeth that a conventional toothbrush cannot access. These small, bristle-headed brushes fit into the spaces between teeth, which account for up to 40% of the total tooth surface area. Their primary function is to disrupt and remove the bacterial biofilm, or plaque, that accumulates in these tight areas. Regular use of IDBs helps prevent gingivitis and other periodontal concerns by targeting plaque buildup at the gum line and between the teeth.
Choosing the Right Brush Size
The effectiveness of an interdental brush depends entirely on selecting the correct size for each gap in your mouth. IDBs are sized based on the diameter of their bristles and central wire core, and manufacturers typically color-code them for identification. The brush must completely fill the space between your teeth to ensure the bristles contact the entire tooth surface on both sides. If the brush slides through easily without friction, it is too small and will not adequately remove plaque.
Conversely, forcing a brush that is too large can cause damage to the gum tissue and potentially injure the enamel surface. You should feel a gentle, snug resistance as you insert the brush, but never sharp pain. It is common to require two or three different sizes of interdental brushes, as gaps between back molars are often wider than spaces between front teeth. Consulting a dental professional for an initial sizing assessment is the most reliable way to determine the precise brush diameters needed.
Mastering the Interdental Cleaning Technique
Once the correct size is confirmed, the technique for using the interdental brush involves a simple, controlled motion designed to maximize plaque disruption. Begin by gently inserting the brush straight into the space between two teeth, positioning it close to the gum line. Aim to insert the brush without twisting or bending the wire, allowing the bristles to fill the available area. If resistance is encountered, use a smaller size.
After the brush is fully inserted, move it horizontally back and forth through the gap a few times (generally two to four strokes) to physically scrape the plaque off the adjacent tooth surfaces. For back teeth, where access is more difficult, a slight curve can be placed in the brush wire to improve maneuverability. Using a mirror during initial attempts helps ensure you target each interdental space effectively. If you have dental hardware, such as braces or implants, guide the brush carefully under archwires or around implant abutments to clean areas where plaque accumulates.
Frequency and Maintenance
Interdental brushes are designed for daily use, and most dental professionals recommend cleaning once a day. The ideal time is typically before brushing your teeth in the evening. Cleaning before brushing allows the removal of food debris and plaque that a toothbrush might otherwise push around the mouth. This routine is important because the bacterial biofilm takes about 24 hours to mature and become more harmful to gum tissue.
After use, the interdental brush must be thoroughly rinsed under running water to remove dislodged plaque and debris. The brush should then be allowed to air dry completely to ensure hygiene between uses. Interdental brushes are reusable tools, but they do not last indefinitely. The tool should be replaced when the bristles show visible signs of wear, such as:
- Becoming frayed
- Splaying out
- If the wire core is significantly bent
- If the wire core cannot be straightened
Depending on the force of use and the quality of the brush, a single interdental brush typically remains effective for about one to two weeks of daily cleaning.