活性炭歯磨きはエナメル質のホワイトスポット病変を汚す可能性がある：4年間のフォローアップ症例報告

Activated charcoal (AC)-containing products have been widely advertised over the internet, but evidence of their efficacy and safety are still scarce. Few studies have addressed their abrasivity and whitening efficacy, but none has addressed their staining potential. Therefore, this study aimed to report irreversible staining caused on enamel white spot lesions (WSLs) after orthodontic treatment caused by AC powder used for toothbrushing. A fifteen year-old patient sought the dental clinic complaining about dark discolorations on maxillary anterior teeth after toothbrushing with a fluoride-free AC powder. The patient reported that white discolorations were present after the orthodontic appliances removal and started using the product due to its 'whitening' claims. Then, due to the dark discoloration, the patient sought another dental professional who conducted microabrasion, but the stains were not completely removed. Therefore, direct veneers were conducted using self-etching adhesive system (FL Bond II) and resin composites (Beautifil II A2O, B2 and incisal) to successfully cover the remaining discoloration. After 4 years, no staining was observed. In conclusion, AC-containing products might not be safe for patients with WSL after orthodontic treatment, and their use might irreversibly stain the demineralized enamel, leading to more invasive treatments to solve the resulting discoloration.