Role of Inhibitor SMADs in Stage 3 Grade B periodontitis before and after periodontal treatment.

OBJECTIVE: This study aimed to examine the levels of transforming growth factor-beta (TGF-beta) and inhibitory-Smads (I-Smads) in saliva and gingival crevicular fluid (GCF) in patients with Stage 3 Grade B periodontitis before and after non-surgical periodontal treatment. BACKGROUND: Recently, it has been stated that Smads play an active role in all conditions where TGF-beta is involved, including periodontal inflammation. METHODS: Twenty healthy participants (control) and 20 patients with Stage 3, Grade B periodontitis were recruited. GCF and saliva samples and clinical periodontal recordings were investigated at the baseline and 1 month after treatment. TGF-beta and I-Smads (Smads 6 and 7) were determined by ELISA. RESULTS: Salivary Smad6 and Smad7 levels were significantly lower in the periodontitis group than healthy controls (p < .05), while there was no difference in salivary TGF-beta levels between groups at baseline (p > .05). The total amounts and concentrations of GCF TGF-beta, Smad6, and Smad7 were significantly lower in the periodontitis group than healthy controls at baseline (p < .05), and then decreased in concentration levels with treatment (p < .001). Positive correlations were found between total amounts and concentrations of GCF TGF-beta, Smad6, and Smad7 (p < .05). CONCLUSION: Our findings revealed that Smad6 and Smad7 in GCF and saliva decreased in periodontitis and then increased after periodontal treatment. Our study suggests that I-Smads act in parallel with TGF-beta in periodontal inflammation and may have a role in the development of periodontitis.