Enhancing Oral Health During Orthodontics with Nano-Hydroxyapatite

Orthodontic treatments can be life-changing, but they also challenge the health of enamel and gums due to the bonding or removal of fixed appliances, and the ease of maintaining good oral hygiene during treatment. Recently, studies have highlighted the potential of nano-hydroxyapatite (n-Ha) to address these challenges. In this blog, we’ll cover key findings about n-Ha’s benefits and practical tips on how patients with fixed braces or clear aligners can incorporate n-Ha -based products, like EvaGlo, into their routines.

Nano-Hydroxyapatite’s Role in Fixed Orthodontic Appliances

Based on recent research, nano-hydroxyapatite has gained attention for its possible applications in orthodontic care for fixed appliances:

1. Pre-Bonding: Improving orthodontic bonding strength
2. Brackets Attached: Preventing white spot lesions around the brackets
3. Post-Bonding: Restoring demineralised enamel

Pre-bonding

The bonding process for braces is critical to prevent bracket failures and ensure effective treatment. Research shows that pre-treatment application of n-Ha—either in the form of a daily-use toothpaste or a high-concentration intensive care product—can help enhance enamel condition and improve bonding.

One study found that using a “remineralisation shock treatment” (not a regular toothpaste) containing 30% n-Ha improved the microhardness and shear bond strength of treated enamel compared to demineralised enamel, however, these properties remained lower than those of intact enamel. This indicates that using an intensive care product with a high concentration of n-Ha (30%) enhances enamel properties which may improve the adhesion of orthodontic brackets and attachments, but enamel that has been immediately treated might still be less robust than natural enamel [1].

Recommendation for Patients Starting Orthodontics:

• Use of n-Ha Toothpaste: A daily-use toothpaste containing 10% n-Ha, such as EvaGlo, is appropriate and beneficial before bonding. It helps restore mineral density in demineralised enamel—which is especially important, as untreated demineralised enamel presents the greatest risk for poor bonding.
• Optional Intensive Care Regimen: In cases where enamel needs additional reinforcement, dental professionals might recommend a short pre-treatment course of an intensive care product containing up to 30% n-Ha. This could further improve enamel condition before bonding.
• Avoid Immediate Application of Intensive Care Products: For best results, discontinue intensive n-Ha treatments (containing up to 30% n-Ha) several days to a week before bracket placement. Regular-strength toothpaste like EvaGlo can be continued during this period, as it helps protect against demineralisation.

Brackets Attached

Orthodontic brackets create challenges for enamel health by increasing the risk of demineralisation. The brackets trap plaque and food debris, creating a microenvironment conducive to acid production by bacteria. This could lead to white spot lesions, surface roughness, and weakened enamel. Incorporating n-Ha into oral care routines during orthodontic treatment can mitigate these effects and support enamel integrity [3].

Why Use n-Ha During Treatment?

• Repairs Demineralised Enamel: Research shows that n-Ha can effectively remineralise enamel around brackets.
• Increased Mineral Deposition: Studies demonstrate that n-Ha significantly boosts calcium and phosphorus levels on the enamel surface. This contributes to a crystalline enamel structure with greater resilience against demineralisation.
• Aesthetic Benefits: By repairing white spot lesions, n-Ha improves enamel appearance. It reduces chalky white spots that often appear around the brackets, and helps treated enamel to blend with adjacent healthy enamel.
• Superior Performance in Acidic Microenvironments: Unlike fluoride, n-Ha continues to remineralise enamel even in acidic conditions. This property makes it particularly valuable for orthodontic patients, as the acidic microenvironment around brackets is a key factor in enamel erosion [4].

Recommendations for Braces Wearers:

• Use a n-Ha Toothpaste: Incorporate a n-Ha toothpaste like EvaGlo into your routine to enhance enamel remineralisation and protection. This can be done as an alternative or alongside daily fluoride toothpaste use.
• Thorough Brushing Around Brackets: Ensure that n-Ha is applied to areas prone to plaque accumulation, particularly around brackets and wires, to target high-risk zones effectively.

Post-Debonding

Once braces are removed, enamel surfaces are often left vulnerable, with micro-cracks and demineralisation that increase roughness and sensitivity. Fluoride toothpastes are commonly recommended for post-treatment care, but studies suggest that n-Ha outperforms fluoride for restoring smoothness and remineralising enamel subsurface layers.

Research indicates that n-Ha:

• Forms a protective layer on the enamel surface, resisting acids and helping shield against future demineralisation.
• Binds directly to enamel, effectively reducing surface roughness and enhancing aesthetics by filling in micro-imperfections.
• Read our article on the mode of action of nano-hydroxyapatite.

Recommendation for Patients Post-Braces:

Using a n-Ha toothpaste after braces removal offers additional enamel reinforcement. A n-Ha toothpaste can be incorporated into the routine along with regular fluoride toothpaste or as a standalone replacement for those who prefer fluoride-free options. Patients who want to maximise enamel health without switching fully from fluoride products will still see notable benefits by supplementing with n-Ha on alternating days [5]. This approach is cost-effective and optimises long-term enamel care.

Clear Aligners: Benefits and Challenges

Clear aligners have gained popularity as an orthodontic treatment, offering aesthetic and comfortable alternatives to traditional braces. Studies reveal that aligners may reduce the risk of white spot lesions and periodontitis compared to fixed braces, making them a favourable choice for individuals with gum health challenges [6]. However, aligners create a unique micro-environment by enclosing the teeth. This reduces salivary flow and can trap food particles and plaque, potentially leading to:

• Cariogenic Plaque Shifts: The enclosed space can promote the growth of cavity-causing bacteria.
• Reduced Remineralisation: Saliva’s natural remineralising properties are diminished, leaving teeth more vulnerable.

Recommendations for Clear Aligner Patients

Maintaining Hygiene Before Reinserting Aligners

• Why It Matters: Plaque and food trapped under aligners can exacerbate demineralisation and microbial imbalances.
• Action: Brush thoroughly after every meal and before reinserting aligners. Use a toothpaste with remineralising ingredients, such as n-Ha and xylitol, to promote enamel health and regulate plaque microbiota.

Innovative Use of n-Ha Toothpaste with Aligners

• Extended Contact Time: applying a thin layer of n-Ha toothpaste to teeth (not the aligner) before inserting aligners, akin to a tooth conditioner or serum, can provide prolonged exposure to remineralising agents. This is particularly beneficial at night when salivary flow is naturally lower.
• Microbiota Regulation: xylitol, combined with n-Ha, can help maintain a healthy plaque balance by inhibiting cariogenic bacteria and buffering acids.

Ensure that excess toothpaste does not come in contact aligner surfaces, as abrasive particles can potentially scratch the aligner surface and increase bacterial adhesion. If you would like to apply, a thin layer of toothpaste before inserting aligners, then it may be favourable to select a mildly abrasive toothpaste. Most whitening toothpastes are known to be more abrasive and might be less ideal for this purpose. We recommend our Kids Strawberry toothpaste for this purpose due to is mild flavour and lower abrasivity.

Routine Cleaning of Aligners

• Avoid cleaning aligners with toothpaste, as abrasives may damage the aligner trays.
• Use non-abrasive cleaning solutions to minimise surface alterations and bacterial buildup.

Final Thoughts

The incorporation of nano-hydroxyapatite in dental care routines is becoming an exciting frontier for supporting the oral health of orthodontic patients. Whether for stronger initial bonding, reduced risk of white spot lesions during attachment, improved enamel health post-debonding, or boosting remineralisation while wearing clear aligners, a nano-hydroxyapatite toothpaste offers significant benefits to all categories. Integrating EvaGlo into your routine, either as your primary toothpaste or a supplemental step, provides a targeted boost to enamel strength. Consult with your dental professional to ensure the best approach for your unique orthodontic journey.