Sir, periodontitis is a chronic infection and inflammation of the periodontium.1 A relationship between periodontal therapy (PT) and reduction in risk of cardiovascular diseases has been reported.2 One hypothesis is that PT reduces the expression of cell adhesion molecules that are pivotal in the pathogenesis of vascular inflammation and atherosclerosis.3 This first meta-analysis included eight studies (three randomised control trials, one prospective non-randomised study, and four retrospective). The main outcome was change in the levels of cell adhesion molecules (soluble endothelial selectin s-E-selectin-1, soluble intercellular adhesion molecule-1 s-ICAM-1, and soluble vascular cell adhesion molecule-1 s-VCAM-1) following PT. Standardised difference in means (SDM) was used for effect size (ES) measurement. An ES of 0.2-0.5 is considered small, 0.5-0.8 is medium, and more than 0.8 is large.

Of the 797 patients (445 in PT, 352 in control), men formed 62.3% (497) with 69.8% (311) and 52.8% (186) in the respective groups; the mean age of patients was 51.9 and 55.89 years respectively. PT included oral hygiene instructions, scaling and root planing, antibiotics, chlorhexidine mouthwashes, tooth extractions and surgical PT. The control group received no treatment. Patients had moderate to severe periodontitis. Follow up varied between 3-6 months. PT showed a positive and medium effect size (SDM 0.52, 95% CI 0.10-0.94) on decreasing s-E-selectin values at follow up. PT did not show a statistically significant effect size on lowering s-ICAM-1 (SDM 0.41, 95% CI - 0.002 to 0.827) and s-VCAM-1 (SDM - 0.047, 95% CI - 0.27 to 0.18).

Thus, PT has a moderate effect in lowering s-E-selectin in patients with moderate to severe periodontitis. E-selectin is expressed by the endothelium and helps in migration of leucocytes to arterial sub-endothelium in an important mechanism by which atherosclerosis starts and progresses. Lowering of E-selectin may be a mechanism by which PT improves endothelial function and cardiovascular outcomes.4 However, our study has limitations. None of the studies checked if the change in the biochemical markers translated into clinical outcomes.