Data sources PubMed database. A manual screening among the references of selected articles. Study selection Original articles, published in English relating to in vivo techniques (concepts /tools) to activity assessment of coronal carious lesions (AACCL).Data extraction and synthesis Two reviewers independently and in duplicate screened the studies. A spreadsheet was used for data extraction and management. Results were described qualitatively.Results Twenty-five articles were included in the review.Conclusions Definition and harmonisation of standards for activity assessment-related concepts/tools is needed. Along with the above, further investigations are needed for in vivo validation of newly developed tools.