assessment the concentration of calprotectin in the saliva of patients with oral lichen planus, in comparison to healthy individuals and its relation with severity of the disease . Background: calprotectin has been shown to play an important role in the pathogenesis of many inflammatory diseases including; psoriasis, and acne vulgaris but was poorly investigated in patients with oral lichen planus. Data Sources: By searching and reviewing Medline databases (Pub Med and Medscape) and looking for studies that examined the possible role of calprotectin in patients with oral lichen planus available till 2022. Study Selection: All studies were independently assessed for inclusion. They were included if they fulfilled the following criteria: 1.Written and published in English language. 2. Published in peer-reviewed journals.3.Explain how the level of salivary calprotectin may be linked to oral lichen planus and how it may affect severity of the disease . Data Extraction: If the studies did not fulfill the inclusion criteria, they were excluded. Study quality assessment factors included whether ethical approval was gained, eligibility criteria specified, appropriate controls , adequate information andwell-defined evaluation measures. Data from each eligible study were independently abstracted using a data collection form to capture information related to our concerned study outcomes. Conclusions: Salivary calprotectin level is increased in patients with oral lichen planus compared to healthy control subjects