The meta-analysis of Mozaffari et al. revealed the heterogeneous salivary IFNγ levels in OLP patients from 0.83 ± 0.54 to 416.67 ± 702.11 pg/mL and in healthy control group from 1.81 ± 0.98 to 52.7 ± 100.51. This evidence concerns the gene IFNG and oral lichen planus.