What really happens between your teeth? The role of bacteria and dental floss
DENTIST'S ADVICE

What really happens between your teeth? The role of bacteria and dental floss

Published on March 27, 2026

Even with regular brushing, some areas of the mouth remain difficult to clean. The spaces between the teeth, called interdental areasThey are particularly affected. Invisible to the naked eye, they nevertheless harbor intense bacterial activity, often the cause of many oral health problems.

What is less well known is that these areas play a key role in the balance of the oral microbiotaWhen they are not cleaned properly, certain bacteria proliferate and can disrupt the entire balance of the mouth.

Today, I'll explain to you what's really going on between your teeth, why bacteria accumulate there, and how the dental floss is an essential step to preserve oral health.

1. Between the teeth: an area conducive to the accumulation of bacteria

Interdental spaces are narrow areas where food particles and bacteria easily accumulate. Unlike the visible surfaces of teeth, these areas are difficult to reach with a regular toothbrush.

These deposits form what is called the plaque, a biofilm composed of bacteria.
Over time, if this plaque is not removed, it becomes a favorable environment for the development of bacteria responsible for:

  • interdental caries,
  • inflammation of the gums (gingivitis),
  • bad breath.

So it is between the teeth that invisible… but very real problems often begin.

2. Bacteria and the oral microbiota: a fragile balance

Not all bacteria in the mouth are bad. oral microbiota is a complex ecosystem, composed of beneficial bacteria that contribute to the protection of teeth and gums.

However, when dental plaque accumulates between the teeth, this balance is disrupted. Certain opportunistic bacteria become dominant and produce acidic or inflammatory substances.
Result:

  • The enamel becomes brittle.
  • the gums become sensitive,
  • and imbalances gradually take hold.

Maintaining a balanced microbiota therefore does not consist of eliminating all bacteria, but of preventing their excessive accumulation in critical areas, such as interdental spaces.

3. Dental floss: the key step to eliminating invisible bacteria

Le Micro-Infused Dental Floss It is one of the only tools capable of effectively cleaning the spaces between teeth. It allows you to remove plaque where a toothbrush cannot reach, thus reducing the bacterial load responsible for imbalances.

When used daily, it helps to:

  • to prevent interdental cavities,
  • protect the gums,
  • to reduce bad breath,
  • and maintain a more balanced oral microbiota.

This simple, often overlooked step makes a real difference to long-term oral health. Combined with gentle brushing and microbiome-friendly care, it helps maintain a healthier and more comfortable mouth.

 

In summary: what's going on between your teeth?

  • Interdental spaces easily accumulate bacteria and residue.
  • This accumulation forms dental plaque, which is the source of many problems.
  • The oral microbiota can become unbalanced if these areas are not cleaned.
  • Dental floss is essential to eliminate these invisible bacteria and maintain the balance of the mouth.

At The SmilistWe believe that oral health relies on simple yet precise actions. Cleaning between your teeth is not a minor detail: it is an essential pillar for maintaining a healthy smile over the long term.

Christiane
Dentist & Co-founder of The Smilist