Whitening efficacy of activated charcoal-based products: A single-blind randomized controlled clinical trial

This randomized controlled clinical trial evaluated the whitening efficacy, tooth sensitivity (TS), and volunteers' satisfaction following the use of activated charcoal powder and toothpaste.

Fifty-six volunteers were randomly allocated into 4 groups (n = 14) according to a 14-day toothbrushing or whitening treatment with activated charcoal powder (ACPW), activated charcoal toothpaste (ACT), regular fluoridated toothpaste (RT), and 10 % carbamide peroxide (CP). Objective (ΔE₀₀) and subjective (ΔSGU) color and whiteness index (ΔWI_D) changes were calculated. Patients self-reported the risk and intensity of TS using a visual analogue scale and the volunteer's satisfaction was determined by a questionnaire. Color assessments were analyzed by Kruskal-Wallis followed by Dwas-Steel-Crithlow-Fligner, and absolute TS risk and volunteer's satisfaction by Fisher exact test (p < 0.05).

ACPW and ACT promoted similar effects in ΔE₀₀, ΔSGU, and ΔWI_D to that observed for RT. No significant difference was found in terms of TS risk intensity. TS risk became high after 7 and 14 days, with higher TS prevalence in CP. Volunteers reported that ACPW exhibited the lowest ease-of-use, comfort, and whitening satisfaction among groups (p < 0.05).

Activated charcoal-based products presented a minor and unsatisfactory whitening effect while CP resulted in optimal tooth whitening and the highest level of satisfaction among volunteers. Risk was higher from 7 days onwards and was more pronounced in the CP.

Based on the whitening effect and patient satisfaction, this controlled-randomized clinical evidence supports that the use of activated charcoal-based products should be discouraged.