Color improvement and stability of orthodontic clear aligners following different cleaning protocols
Makaleler > Tam Makale · 2026
Yazarlar: Aslı Aşık, Yağmur Lena Sezici, Enver Yetkiner, Arzu Aykut Yetkiner, Nazan Ersin
Clinical Oral Investigations, Uluslararası, Wos, 2026, cilt 30
DOI: 10.1007/s00784-026-06861-4
Özet
OBJECTIVES: To evaluate the color improvement and stability of clear aligners after applying different hydrogen peroxide-containing and hydrogen peroxide-free cleaning protocols under simulated in-vitro conditions. MATERIALS AND METHODS: Clear aligners (Invisalign, Align Technology, San Jose, CA, USA) were immersed in coffee for 7 days (n = 24). They were then subjected to cleaning with four different chemical solutions: hydrogen peroxide-free – Group 1: Invisalign Cleaning Crystals (Align Technology, San Jose, CA, USA) and Group 2: Aktident gel (Rego X-ray GmbH, Augsburg, Germany); hydrogen peroxide-containing – Group 3: Corega Proguard (Stafford-Miller Limited, Waterford, Ireland) and Group 4: Steradent Blancheur Pro (Reckitt Benckiser Healthcare Limited, Hull, UK). Specimens were exposed to the different solutions according to manufacturer’s instructions, followed by a second 7-day discoloration cycle. Color (ΔE*, L*, a*, b*) were assessed at baseline, after a 7-day coffee exposure, after cleaning, and after the second discoloration using a spectrophotometer (Vita Easyshade Compact Advance, VITA Zahnfabrik, Bad Säckingen, Germany). Surface alterations were qualitatively analyzed using a scanning electron microscope (SEM). RESULTS: After the initial discoloration, ΔE values significantly increased in all groups and decreased following cleaning (p < 0.01), indicating partial color recovery. However, a subsequent restaining cycle caused a renewed increase in ΔE (p < 0.05). Although no significant intergroup differences were detected (p > 0.05), a significant intragroup difference between the first and second discoloration cycles was found in the peroxide-containing groups (Corega Proguard and Steradent Blancheur Pro) (p < 0.05). A negative correlation between pH and ΔE₂ was observed in the peroxide-free group (r = − 0.64, p < 0.05). CONCLUSION: Although both hydrogen peroxide-containing and peroxide-free cleaning agents effectively reduce discoloration, variations in their pH and chemical composition influenced their efficacy. The differences in surface alterations among the cleaning agents highlight the need for a comprehensive assessment before recommending specific products to patients for aligner maintenance. CLINICAL RELEVANCE: Clinicians should consider the chemical composition and pH of cleaning agents when advising patients on aligner maintenance to avoid unwanted surface or color alterations.