Background: Systemic inflammation is increasingly being recognized as a risk factor for adverse cardiovascular events. Evidence is accumulating that associates periodontal disease with a higher risk for atherosclerotic plaque formation. A positive association between circulating C-reactive protein (CRP) levels and periodontal disease may be responsible for these observations. We undertook a systematic review and conducted a meta-analysis of the available evidence to examine the effect of periodontal treatment on systemic CRP levels and to assess the quality of the available evidence.
Methods: We conducted a systematic search of the English-language literature on the effect of periodontal treatment on CRP levels, as assessed by high-sensitivity assays, at least 2 months after periodontal treatment. The search was conducted in MEDLINE between 1966 and July 2005 and the Cochrane Central Register of Controlled Trials. We performed a meta-analysis using the DerSimonian and Laird random-effects model.
Results: The literature search yielded 814 citations of which 10 met the inclusion criteria. The meta-analysis of the randomized controlled trials (RCTs) showed that the difference in serum CRP levels is not significantly different between the two arms. Similarly, results from the single-cohort studies showed that the difference on serum CRP levels was not significantly different before and after treatment.
Conclusions: There is now a large body of evidence to indicate that systemic inflammation is present in patients with periodontal disease. Thus, information from RCTs and single-cohort studies does not support the hypothesis that periodontal treatment can reduce systemic CRP levels.