complements c3 and c4 in serum and stimulatedsaliva of patients suffer oral erosive lichen planus

Introduction: the objective of this study was to compare the level of complements c3 and c4 in serum, and stimulated saliva between oral lichen planus (olp) and healthy individuals. methods: a case-control study was performed on 31 healthy and 31 who suffer the erosive type of olp. serum and saliva level of c3 and c4 were measured by immunoturbidimetry method. results: c3 and c4 were expressed at a lower level in serum and saliva of olp patients compared to control groups. serum c3 and c4 levels did not correlate with their saliva levels. the receiver operating characteristic analysis showed significantly diagnostic abilities for serum and saliva c3 and c4 to discrimination of olp patients from controls (cutoff [mg/dl] for c3 were 83 in serum and 3.45 in saliva and for c4 were 9.5 in serum and 0.9 in saliva). conclusion: serum and salivary levels of total c3 and c4 were lower in patients with olp than in healthy controls. therefore, they may able to discriminate olp from healthy.