Orthodontics and cavities: how metal braces compromise dental hygiene

Brushing your teeth with braces is a daily challenge. Stains, interproximal cavities, gingivitis: the oral risks associated with fixed appliances are real. What you can do to limit them.

Maintaining perfect oral hygiene during an orthodontic treatment with braces is a real technical challenge. Brackets, archwires and ligatures create a complex oral environment where bacterial plaque accumulates in areas that an ordinary toothbrush cannot reach. The result: a documented increase in cavity risk in patients wearing conventional fixed appliances.

1. Why braces make hygiene so difficult

A fixed orthodontic appliance triples the number of surfaces to clean. Each bracket has four corners that accumulate plaque. The metal wire creates a horizontal barrier preventing normal flossing. Elastic ligatures, when used, absorb food dyes and bacteria. In practice, even a motivated and meticulous patient typically spends between 12 and 20 minutes brushing their teeth correctly with braces — compared to 2 to 3 minutes without an appliance.

2. Types of cavities specific to brace wearers

Cavities that develop during orthodontic treatment with braces have distinctive characteristics:

• Cervical cavities: developed at the junction between the bracket and the gum, often invisible during treatment
• Interproximal cavities: between teeth, where dental floss can no longer pass normally
• Peri-bracket demineralisation: the infamous "white spots" that appear around brackets and persist after removal
• Subgingival cavities: that develop under the gingival margin, invisible to the naked eye and detectable only by X-ray

3. Epidemiological data on cavity risk

Studies published in major orthodontic journals are unequivocal: patients undergoing fixed orthodontic treatment have a significantly higher cavity risk than untreated patients or those treated with removable aligners. A systematic review published in the Journal of Orthodontics reports that the prevalence of demineralisation lesions in brace wearers ranges from 38 to 72% depending on the populations studied. These initial lesions can progress to actual cavities if treatment is not adapted.

4. Precautions you must take if you wear braces

• Brush teeth after every meal — minimum 3 times daily with a small-headed brush
• Systematically use interdental brushes (size 0.5 to 0.9 mm depending on spaces)
• Supplement with an oral irrigator (water flosser) for inaccessible areas
• Apply concentrated fluoride gel (5000 ppm) every evening by brushing or in a tray
• Avoid sticky foods, slow-release sugars and sugary or acidic drinks
• Consult a dental hygienist every 3 months throughout the treatment

5. What removable aligners allow

The cardinal advantage of clear aligners over conventional braces is their removability. The patient removes the trays before eating and before brushing. Brushing and flossing are done as before treatment — without mechanical obstacles, without interdental brushes, without a 15-minute complex protocol. This fundamental property makes aligners a solution far more compatible with maintaining good oral hygiene, and therefore with preserving dental capital.

Conclusion

If you are considering orthodontic treatment, the question of oral hygiene must be at the heart of your decision. Metal braces impose a demanding hygiene protocol that many patients do not maintain optimally over 18 to 24 months. Clear aligners eliminate this constraint. Discuss your eligibility for clear aligners with a certified dentist before starting any treatment.