Abstract
The aim of this systematic review was to answer the question of whether crack cocaine can induce cellular and molecular alterations and whether such alterations are somehow related to clinical lesions in the oral mucosa. The searches were undertaken in three electronic databases and conducted based on the PRISMA 2020 statement. Eleven studies published between 1994 and 2020 were analyzed. The quality of the included studies was assessed by two independent reviewers (TGP and DAR) through a confounder's categorization methodology, in which final ratings were attributed (strong, moderate or weak) for each study. From 11 studies included, 7 evaluated the cellular/molecular impact of the addiction in a total of 492 individuals and compared to a control (non-exposure) group (n = 472). The main tests used for cellular alteration were MN and AgNORs. Cells from crack cocaine groups exhibited increased proliferation and MN counting. Only four studies evaluated the prevalence of oral lesions. All of them showed that individuals exposed to crack cocaine presented an increased number of oral lesions. Most studies showed good quality. In conclusion, our results demonstrate that crack use may induce changes at the cellular and molecular level and also exhibit an increased number of oral lesions. However, a correlation between such changes and oral mucosa lesions still needs further investigation and elucidation through other clinical studies in humans.