Inflammation and tissue remodeling mediator expression during gingivitis: A comparison between experimental, naturally occurring gingivitis, and periodontal health.

Abstract

The aim of this study is to evaluate the immune regulation and tissue remodeling responses during experimental gingivitis (EG) and naturally occurring gingivitis (NG) to provide a comprehensive analysis of host responses. Gingival crevicular fluid (GCF) was obtained from 2 human studies conducted in university settings. The EG study enrolling 26 volunteers provided controls for the baseline (Day 0) from healthy disease-free participants, while Day 21 (the end of EG induction of the same group) was used to represent EG. Twenty-six NG participants age-matched with those of the EG group were recruited. GCF samples were analyzed for 39 mediators of inflammatory/immune responses and tissue remodeling using commercially available bead-based multiplex immunoassays. The differences in GI and mediator expression among groups were determined at a 95% confidence level (p ≤ 0.05) by a 2-way analysis of variance (ANOVA) with a post-hoc Tukey's test. Our findings showed that EG had a greater gingival index than NG and was healthy (p<0.01 of all comparisons). Furthermore, EG showed significantly higher levels of MPO (p<0.001), CCL3 (p<0.05), and IL-1B (p<0.001) than NG. In contrast, NG had increased levels of MIF (p<0.05), Fractalkine (p<0.001), angiogenin (p<0.05), C3a (p<0.001), BMP-2 (p<0.001), OPN (p<0.05), RANKL (p<0.001), and MMP-13 (p<0.001) than EG. Consistent with the findings from chronic (NG) versus acute (EG) inflammatory lesions, these data reveal that NG displays greater immune regulation, angiogenesis, and bone remodeling compared to EG.