Treatment of periodontitis and C-reactive protein: A systematic review and meta-analysis of randomized clinical trials

Background: Systemic inflammation is implicated in the onset and progression of several chronic diseases. Periodontitis is a potential trigger of systemic inflammation. Purpose: To comprehensively appraise all the evidence on the effects of the treatment of periodontitis on systemic inflammation assessed by serum C-reactive protein (CRP) levels. Data Sources: Six electronic databases were searched up to 10 February 2022 to identify and select articles in English language only. Study Selection: Twenty-six randomized controlled clinical trials reporting changes amongst 2579 participants about CRP levels at 6 months or more after treatment. Data Extraction: Two reviewers independently extracted data and rated the quality of studies. Meta-analyses were performed using random and fixed effect models. Risk of Bias: Risk of bias (RoB 2.0 tool) and quality of evidence (GRADEpro GDT tool) analyses were completed. Data Synthesis: Treatment of periodontitis reduced CRP levels by 0.69 mg/L (95% confidence interval: −0.97 to −0.40) after 6 months, but limited evidence was retrieved from studies with longer follow-ups. Similar findings were observed in participants with other co-morbidities in addition to periodontitis. Greatest reductions were observed in participants with concentrations of CRP >3 mg/L at baseline. Limitations: High level of heterogeneity. Conclusions: Treatment of periodontitis reduces serum CRP levels (up to 6 months follow-up) to a degree equivalent to that observed after traditional lifestyle or drug interventions. This evidence supports a causal association between periodontitis and systemic inflammation.