A complete oral hygiene routine involves more than just a toothbrush. While brushing cleans the outer, inner, and chewing surfaces of the teeth, it fails to reach nearly 40% of the total tooth area. Interdental aids are specialized tools designed to mechanically disrupt and remove plaque, the sticky bacterial film, from the surfaces between adjacent teeth. These devices are available in various forms, each tailored to address the unique contours and spacing within the mouth. Using these tools daily is fundamental for maintaining long-term oral health.
The Necessity of Interdental Cleaning
The areas between teeth and beneath the gumline provide sheltered environments where plaque biofilm thrives, leading to dental disease. If this bacterial layer is not regularly removed, minerals in saliva cause it to harden into calculus or tartar, which cannot be removed by brushing alone. This accumulation triggers an inflammatory response in the gum tissue, known as gingivitis, causing the gums to become red, swollen, and prone to bleeding.
If gingivitis is left unaddressed, the inflammation can progress deeper into the supporting structures of the teeth, leading to periodontitis. This serious infection causes the detachment of the gum tissue from the tooth surface, creating periodontal pockets that harbor more bacteria. Periodontitis results in the irreversible loss of the bone and ligament that hold the teeth in place, eventually leading to tooth mobility and loss. Daily interdental cleaning is the primary method for controlling this interproximal biofilm and preventing the progression of gum disease.
Categorizing Interdental Tools
Interdental devices can be grouped into three main categories based on their mechanism of action: manual filament, mechanical brush, and pressurized fluid. Each category offers distinct advantages depending on the user’s dexterity and the anatomical needs of their mouth.
Manual Filament Aids
Dental floss remains a common choice, consisting of a thin string of nylon or PTFE (polytetrafluoroethylene) manually guided between teeth. Floss works by scraping plaque off the smooth surfaces of the teeth where they touch, and it is most effective in individuals with tight contact points. Dental tape is a wider, flatter variation of floss, sometimes preferred for slightly more spaced teeth, offering a broader cleaning surface. Floss threaders are simple loops used to carry traditional floss under fixed dental work, such as bridges or orthodontic wires, allowing access to otherwise blocked areas.
Interdental Brushes
Interdental brushes are small, disposable cleaning devices featuring a central wire core wrapped with fine nylon filaments, resembling a miniature bottle brush. These brushes are designed to fill the entire space between teeth, providing a scrubbing action often more effective than floss for plaque removal in wider spaces. The correct size is determined by the “Passage Hole Diameter” (PHD), the smallest opening the brush can pass through without the wire bending. Interdental brushes are color-coded according to the International Organization for Standardization (ISO) size standard, typically ranging from 0.4 mm to 1.5 mm. They must fit snugly but without forcing, as multiple sizes may be needed for different areas of the mouth.
Powered and Specialized Aids
Powered oral irrigators, commonly known as water flossers, use a motor to deliver a pulsating, pressurized stream of water or mouthwash to clean between the teeth and below the gumline. The pulsed stream creates a hydrokinetic energy effect that flushes out loose debris and non-adherent plaque. This method is useful for cleaning around complex dental work, such as braces, implants, and permanent retainers, where traditional manual aids are difficult to maneuver. Specialized soft picks, made of rubber or elastomer, provide a gentle, flexible alternative for interdental cleaning, often preferred by individuals with sensitive gums.
Selecting the Right Aid for Your Specific Needs
The selection of an appropriate interdental aid should be a personalized process guided by the anatomy of the mouth and the user’s physical ability. For individuals with naturally tight contacts where teeth meet without visible space, traditional floss is the most suitable option, as a brush cannot be inserted. The thin profile of floss allows it to slide through narrow gaps to clean the contact surfaces.
Conversely, for those with naturally wider spaces, or spaces created by gum recession or bone loss, an interdental brush is recommended. The brush must be selected so that its bristles gently touch the surfaces of both teeth and the gum tissue. If the brush requires excessive force to enter the space, a smaller size is necessary to prevent trauma.
Patients with fixed orthodontic appliances or dental implants often find water flossers most practical. The pressurized water stream can reach around wires, brackets, and implant abutments that are impossible to clean thoroughly with a brush or floss alone. For older adults or individuals who struggle with fine motor skills, a floss pick or a water flosser may simplify the process.
Proper Technique for Effective Use
Each type of interdental aid requires a specific technique to maximize plaque removal while avoiding damage to the gum tissue. When using traditional string floss, an 18-inch section should be used, reserving a clean segment for each interdental space. The floss must be guided gently between the teeth using a slight back-and-forth motion, avoiding a forceful snap that can injure the gums.
Once the floss reaches the gumline, it must be curved into a “C” shape, wrapping around one tooth, and then slid slightly into the sulcus (the space between the tooth and the gum). The floss is moved up and down along the side of the tooth several times, and the process is repeated on the adjacent tooth before moving to the next gap.
For an interdental brush, the correct size is inserted straight into the space without forcing the wire or plastic coating against the gum. The brush is then moved horizontally in and out of the space three to four times to scrub the surfaces. Water flossers require the user to lean over a sink, placing the tip at a 90-degree angle to the tooth surface, and tracing the gumline to allow the pulsating water to clean the interdental space and periodontal pocket.