Effectiveness and abrasiveness of activated charcoal as a whitening agent: A systematic review of in vitro studies.
Level 5 - mechanism / opinion, no new human data
Systematic review of in vitro (extracted teeth/bench) laboratory studies
PubMed 36183933 · doi:10.1016/j.aanat.2022.151998
What was done
Authors conducted a systematic review across PubMed, Web of Science, and Scopus searching for English-language studies evaluating the whitening efficacy and safety (abrasiveness) of activated charcoal-based toothpastes on humans or extracted teeth. Out of 208 identified articles, 11 in vitro studies met inclusion criteria and underwent qualitative synthesis and risk of bias assessment.
What was found
The abstract reports no quantitative pooled metrics or specific numerical values. Qualitatively, risk of bias across the 11 included studies was determined to be medium to high. For whitening efficacy, findings varied: some studies showed no significant differences compared to other treatments, while others found activated charcoal was not the most effective whitening agent. For abrasiveness, most included studies agreed that activated charcoal toothpaste demonstrated higher abrasive potential than alternatives.
Why it matters
This review highlights that popular commercial activated charcoal toothpastes lack strong evidence for superior whitening and carry safety concerns regarding increased enamel abrasiveness.
Limits
All included evidence comes from in vitro laboratory designs rather than clinical in vivo trials. The abstract notes a medium-to-high risk of bias among the 11 included studies, provides no quantitative data or effect sizes, and exhibits heterogeneity in results across evaluated treatments.
Cited by
- supports Charcoal in toothpaste has no intrinsic whitening effect and functions only through adsorption of tannins from the tooth pellicle.