Interleukin-6 polymorphisms modify the risk of periodontitis: a systematic review and meta-analysis

Objective: To clarify the association of IL-6 polymorphisms and periodontitis, a meta-analysis of case-control studies and a systemic review were conducted. Material and methods: We performed a literature search using PubMed and Medline database to May 2009, with no restrictions. We also reviewed references from all retrieved articles. Six case-control studies involving 1 093 periodontitis cases and 574 controls were selected for meta-analysis to assess the purported associations between IL-6 polymorphisms and the risk of periodontitis. IL-6 −174 G/C and −572 C/G polymorphisms were included in the present meta-analysis, and the association between IL-6 −6331 T/C polymorphism and the risk of periodontitis was adequately reviewed as well. Results and conclusion: The present meta-analysis indicates that the IL-6 −174 G allele could not modify the risk of chronic periodontitis, but increased the risk of aggressive periodontitis. And −572 C/G polymorphism is associated with the pathogenesis of periodontitis, including chronic periodontitis or aggressive periodontitis