ABSTRACT
Objective:To investigate the expression of miR-146a and miR-155 in gingival crevicular fluid (GCF) of patients with peri-implantitis and their relationships with bone resorption.Methods:80 implants of 80 patients with peri-implantitis from October 2015 to December 2018 were selected as the disease group and 80 implants of 80 peri-implant healthy persons checked at the same time were selected as the control group. The GCF of the examined teeth was collected with moisture absorbent paper tips; the expression levels of miR-146a and miR-155 in GCF were detected by quantitative real-time polymerase chain reaction (qRT-PCR); the alveolar bone absorption around the implant was measured by X-ray; the levels of inflammatory factors such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), osteopontin (OPN) in GCF were detected by enzyme-linked immunosorbent assay (ELISA); Pearson method was used to analyze the expression levels of miR-146a and miR-155 in GCF and their correlations with bone resorption, IL-1β, TNF-α and OPN levels.Results:Compared with control group, probe depth (PD) (4.56±0.73)mm, plaque index (PLI) (2.21±0.44), sulcus bleeding index (SBI) (2.69±0.32), bone resorption (1.86±0.34), and miR-146a (2.46±0.43), miR-155 (4.20±0.57), IL-1β (75.48±10.29)ng/ml, TNF-α (54.16±9.23)ng/ml and OPN levels (252.41±42.03)pg/L in GCF were significantly higher than those in the disease group [(1.47±0.26)mm, (1.02±0.19), (0.94±0.21), (0.47±0.09), (0.97±0.16), (1.03±0.21), (44.52±8.14)ng/ml, (21.45±4.27)ng/ml, (181.91±36.28)pg/L] (all P<0.05). Pearson analysis showed that the levels of miR-146a and miR-155 in GCF of patients with peri-implantitis were positively correlated ( r=0.558, P<0.05), and they were correlated with bone resorption, IL-1β, TNF-α and OPN levels respectively ( r=0.554, 0.606, 0.521, 0.499; 0.515, 0.653, 0.585, 0.542; all P<0.05). Conclusions:MiR-146a and miR-155 are highly expressed in gingival crevicular fluid, which are positively correlated, and may affect bone resorption in patients with periimplantitis through inflammatory reaction.