The Effects of Activated Carbon Toothpastes on Orthodontic Elastomeric Chains—An In Vitro Study

Objectives: Using toothpaste with activated carbon might increase the decay of orthodontic elastomeric chains’ (ECs) tensile strength, thereby compromising orthodontic treatment. Therefore, this study aimed to evaluate the influence of activated charcoal toothpaste on orthodontic ECs. Materials and Methods: A total sample of 180 EC segments from 3M Unitek^®, Ormco^® and Ortho Classic^® brands were equally divided into 12 groups, each comprising 15 specimens. These pieces were kept in artificial saliva at 37 °C and brushed twice daily for 28 days, with three distinct types of toothpaste: Colgate^® Total, Colgate^® Max White, and Dr Organic^® Extra Whitening Charcoal Toothpaste. The latter two toothpastes contain activated charcoal. Tensile strength, resistance to rupture and colour variation were evaluated at time zero and day 28. Descriptive statistics, one-way ANOVA and Tukey HSD tests were performed at p ≤ 0.05. Results: Toothpaste with and without activated carbon significantly reduced the tensile strength and resistance to rupture of the ECs, and altered EC colour (p < 0.0001). There was inconsistency in the effect of the activated carbon on EC characteristics, most probably due to the different compositions of the ECs and percentages of whitening agents in the toothpastes. Conclusions: The material composition of ECs contributes to their tensile strength decay, resistance to rupture and colour change over time. The variable percentage of activated carbon in a toothpaste likely underlies the different effects observed, depending on the EC brand. Clinical Relevance: It might be reasonable to advise patients wearing ECs to avoid using toothpaste with activated carbon until further evidence becomes available.