Understanding white spot lesions: the hidden risk of poorly cleaned aligners

While aligners offer a discreet and effective solution for straightening teeth, they can also come with a unique set of challenges, particularly with regards to your oral health. Poor aligner maintenance and cleaning can contribute to the buildup of plaque and residue on teeth, which is associated with enamel demineralisation over time. We will delve into what white spot lesions are, how they are linked to poorly cleaned aligners, and what you can do to prevent them.

What are white spot lesions?

White spot lesions (WSLs) are early signs of enamel demineralisation, appearing as opaque or ‘milky’ white spots on the teeth. Their white appearance is the result of mineral loss both on the surface and deeper into the enamel, which reflects light in a different way and makes the affected areas appear dull and white in colour. 

Traditionally associated with traditional fixed metal braces, affecting just over 45% of patients, this sign of decalcification is now also recognised to be a side effect of aligner treatment. One study found that 35% of aligner patients were affected by the development of at least one WSL over the course of their treatment. The appearance of WSLs indicates the early stages of tooth decay, where minerals like calcium and phosphate are leached from the enamel. This process weakens the enamel, making it more susceptible to further decay and cavities.

How does aligner treatment affect WSLs?

Clear aligners, such as Invisalign, are designed to fit snugly over your teeth, and so create an environment that easily traps food particles, plaque, and bacteria. If you are not properly and regularly disinfecting your aligners, these particles stay in contact with your teeth for extended periods of time, increasing the risk of enamel demineralisation and the formation of WSLs. So, why is this a problem?

Plaque buildup and acid production:

When plaque forms on teeth, it can create an environment where acids are produced, which may contribute to enamel demineralisation over time. Changes in the oral environment, such as reduced pH, are associated with this process. If aligners are not cleaned regularly, plaque can accumulate on the appliance and transfer to the teeth, especially in areas that are difficult to reach with toothbrushing, and even string flossing.

Prolonged exposure:

With aligners being worn for 20-22 hours a day, these acids can linger and biofilm may develop over time. One study found that poor oral hygiene and cleaning during orthodontic treatment causes biofilms, which ‘disturbs the balance of the demineralisation and remineralisation processes’.

Saliva flow:

Saliva is essential to maintaining a healthy oral microbiome, breaking down food and washing harmful particles away. Wearing aligners disrupts saliva’s natural cleaning action, as the active enzymes in the saliva cannot reach the teeth as well as without the plastic coverage. To avoid further complicating the oral environment, it is recommended to keep your aligners as clean as possible.

Preventing white spot lesions

To prevent white spot lesions and ensure your aligner treatment is both effective and safe for your teeth, it's crucial to maintain a rigorous cleaning routine. Patients in this study even noted that WSLs played a negative role in how aesthetically satisfied they were with the final treatment result. They also acknowledged that it was ultimately the patient’s responsibility to prevent the formation of WSLs. With this in mind, here are some steps you can take to protect your enamel and prevent WSLs:

Clean your aligners daily 

Instead of brushing your oral appliance and etching micro-scratches into its surface, opt for the gentle and effective clean delivered by ultrasonic technology. Microabrasions in clear aligner plastics and retainers become environments ripe for bacterial growth. Cleaning with even a soft-bristled toothbrush not only fails to reach this bacteria, but it creates further damage to your appliance’s integrity.

The Dental Pod ultrasonic cleaning machine has been specifically engineered for oral appliances, supporting a consistent cleaning routine. The Dental Pod uses 42,000 Hz ultrasonic waves to create cavitation, where microscopic bubbles act on the surface of the appliance to help dislodge plaque, debris and buildup from hard-to-reach areas without the need for abrasive scrubbing. View the Dental pod here.

For an actively remineralising effect when on the go, add Zima Fresh oral appliance spray to your daily routine. This mint spray is formulated with vitamin-rich ingredients and xylitol, offering a convenient way to freshen your mouth and support your daily oral care routine. Simply spray onto your aligners or into your mouth throughout the day as part of maintaining a fresh and comfortable oral environment.

Brush and floss regularly

Keep up with your regular oral hygiene routine by brushing at least twice a day and flossing daily. This supports the Dental pod’s cleaning as it helps remove food particles and plaque from your teeth before you put your clean aligners back in.

Avoid sugary foods and drinks

Reduce your intake of sugary and acidic foods and drinks, as they increase your risk of plaque formation, consequent acid production, and create a lower pH environment prime for demineralisation.

White spot lesions are a common, and unfortunate, but preventable issue associated with aligner treatments. Understanding the importance of proper aligner hygiene and maintaining a consistent cleaning routine can help support the condition of your enamel over time. With the right tools and habits, you can maintain your aligners comfortably as part of your daily oral care routine.