Abstract: Objective: To explore the relationship between IFN-γand oral lichen planus. Methods: A systematic electronic search to hunt for any case control study about IFN-γ with lichen planus was established in the following databases: PUBMED, MEDLINE (OVID), EMBASE.com for papers in English language; CNKI for papers in Chinese language. Two investigators selected the original papers according to inclusive and exclusive criteria, described and evaluated the papers included in this review, then extracted the data independently. The different decisions between two investigators were discussed between each other. RevMan 5.0 from Cochrane was employed in data analysis of meta analysis.Results: 4 papers in Chinese and 3 papers in English were included in this review. There were no significant difference in the levels of IFN-γ in serum and saliva between OLP patients and healthy donors. There was no difference in the level of IFN-γ in saliva between erosive OLP (eOLP) patients and healthy donors, so was reticular OLP (rOLP) patients. There was no difference in the levels of IFN-γ in saliva between eOLP patients and rOLP patients. The positive rate of IFN-γ in tissue of OLP patients was significantly higher than healthy donors (P<0.01). Conclusion: IFN-γ may play an important role in OLP. However, more studies with high quality are expected to explore these fields.

Key words: Oral lichen planus , Immune, IFN-γ, Meta analysis