White spot lesions (WSLs) appear as opaque, chalky white spots on the enamel surface, signaling early enamel demineralization and tooth decay. These blemishes are common among individuals undergoing orthodontic treatment, often noticeable after braces are removed. While primarily a cosmetic concern, their presence indicates mineral loss from the tooth structure.
How White Spot Lesions Form with Orthodontics
Orthodontic appliances, such as brackets, wires, and bands, create an environment where white spot lesions can form. These devices introduce numerous surfaces and crevices where food particles and plaque, a sticky film of bacteria, accumulate and are challenging to remove through routine oral hygiene practices. Plaque buildup can occur as early as four weeks into treatment.
Bacteria within the plaque metabolize carbohydrates from food, producing acids that lower the pH level in the oral environment. When the pH drops below a certain threshold, these acids begin to dissolve minerals like calcium and phosphate from the tooth enamel, leading to demineralization. This mineral loss makes the enamel porous and alters its light-scattering properties, resulting in the characteristic milky white appearance of WSLs. The irregular surfaces created by composite residues around brackets can further increase plaque accumulation, exacerbating this demineralization process.
Preventing White Spot Lesions During Orthodontic Treatment
Preventing white spot lesions during orthodontic treatment requires diligent oral hygiene and careful dietary choices. Patients should brush their teeth for two minutes, twice daily, using a fluoride toothpaste. Specific brushing techniques are helpful, such as angling the toothbrush around brackets and using interdental brushes for hard-to-reach areas.
Flossing is also important; floss threaders or specialized orthodontic floss can assist in cleaning between teeth and around wires. Limiting the consumption of sugary and acidic foods and drinks is advised, as these contribute to acid production and enamel erosion.
Fluoride plays a significant role in strengthening enamel and promoting remineralization, the process of restoring lost minerals. Daily use of fluoride toothpaste is beneficial, and fluoride mouthwashes, such as those containing 0.05% sodium fluoride, can further reduce demineralization. Dental professionals may also recommend in-office fluoride applications, such as high-concentration fluoride varnishes, which are applied directly to the teeth and release fluoride over several hours. Some orthodontic materials, like fluoride-releasing bonding systems around brackets, can help mitigate acidity.
Addressing Existing White Spot Lesions
For existing white spot lesions after braces are removed, several treatment options are available to improve their appearance and strengthen the enamel. Remineralization therapies are often the first approach. These include prescription-strength fluoride applications, such as high-concentration fluoride toothpastes or gels, applied by a dentist or at home. Products containing calcium phosphate can also be applied directly to the white spots to help replenish lost minerals. Varnishes containing both fluoride and CPP-ACP can be effective in promoting remineralization and fluoride uptake.
Microabrasion is another technique; it involves gentle removal of a thin outer layer of affected enamel using a mild acid and an abrasive paste. This procedure can improve the appearance of mild to moderate white spot lesions by revealing healthier enamel underneath. While effective for superficial demineralization, microabrasion may not completely remove deeper lesions.
Resin infiltration is a minimally invasive procedure that involves applying a low-viscosity resin to the etched enamel surface. This resin penetrates and fills the porous demineralized areas, which makes the lesion less visible by altering its refractive index to match the surrounding healthy enamel. This treatment can also strengthen the tooth and prevent the progression of early-stage cavities.
For severe or persistent white spot lesions, more extensive cosmetic treatments may be considered. These include dental bonding, where a tooth-colored composite resin covers the affected area and matches the natural tooth shade. In cases of extensive enamel erosion, dental veneers, thin shells placed over the tooth surface, can be an option to restore both aesthetics and protection. Consulting with a dental professional is important to determine the most appropriate treatment plan for individual cases.