White spot lesions during orthodontic clear aligner therapy: A scoping review

BACKGROUND: White spot lesions (WSL) are an unsightly and a rather frequent drawback of orthodontic treatment. The complex design of fixed orthodontic appliances (FAs) makes it difficult to perform proper oral hygiene, which amounts to white spot lesions being three times more prevalent in patients wearing orthodontic appliances. As clear thermoplastic aligners (CAs) are removable appliances, it has been speculated that they allow better oral hygiene maintenance and thus less incidence of WSLs. OBJECTIVES: This evidence-based scoping review aims to identify the scope and nature of the evidence on white spot lesions during orthodontic clear aligner therapy. TYPES OF STUDIES REVIEWED: Strategic and thorough search of the literature for randomized Controlled Trials, Case-Control, Cohort studies, Case reports, full research articles, and review papers on humans published in English in five major databases was undertaken till July 2021 using free text and Medical Subject Headings (MESH) terms, followed by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to identify five studies for data extraction. RESULTS: Evidence was summarized for study characteristics, diagnostic methods for the detection of white spot lesions, and incidence of white spot lesions during clear aligner therapy. The literature supports that orthodontic treatment with CAs was associated with a low incidence of WSLs when compared with fixed mechanotherapy, with a major role of patient education, motivation, and compliance in maintaining oral hygiene. PRACTICAL IMPLICATIONS: The general perception is that clear aligners are more hygienic and show no incidence of white spot lesions. However, our scoping review supports that WSLs can occur with this form of orthodontic treatment also. WSLs in clear aligners could be attributed to the practice of having composite attachments that cover a significant portion of the tooth surface. Thus, regardless of the type of appliance used, a periodic reinforcement by the orthodontist to maintain oral hygiene is necessary for patient motivation, allowing for better oral hygiene practice, and as a result, leads to prevention of WSLs.