Over-the-counter products in tooth bleaching: A scoping review

Objective: To map and summarize the current scientific evidence concerning the active ingredients, effectiveness, and adverse effects of over-the-counter (OTC) bleaching products. Data and source: This study was conducted according to the PRISMA-ScR guidelines for scoping reviews and registered on the Open Science Framework platform. Study selection: Database searches were conducted in PubMed/MEDLINE, Embase, and Scopus up to January 2024. All in vitro, in situ, and clinical studies evaluating the effectiveness and adverse effects of OTC bleaching products were included. A descriptive analysis of the included studies was performed. Results: A total of 88 studies were included. Most of them were in vitro studies (n = 49), followed by randomized clinical trials (n = 28). The main OTC bleaching products identified were whitening or stain -removing toothpastes (n = 42), followed by whitening strips (n = 39). Most clinical studies indicate that whitening strips are effective in improving tooth color and providing whitening benefits. In contrast, the bleaching effectiveness of toothpastes, mouth rinses and whitening trays was mainly supported by in vitro studies. The main adverse effects associated with OTC bleaching agents were tooth sensitivity and gingival irritation. Conclusion: A wide variety of OTC bleaching products is available for consumer self-administered use. Clinical studies have mainly confirmed the bleaching effectiveness of whitening strips, while the validation for toothpastes, mouth rinses and whitening trays has mainly relied on in vitro studies. Nevertheless, the use of OTC bleaching products may result in adverse effects, including tooth sensitivity, gingival irritation, and enamel surface changes. Clinical Significance: Some over-the-counter bleaching products may have whitening properties supported by clinical studies, particularly those containing hydrogen or carbamide peroxide. Nonetheless, clinicians must be aware of the potential risks associated with excessive self -administration of these products, which may result in adverse effects.