SIRT1 and periodontitis: The SIRT1 rs7895833 AG genotype was associated with 2-fold increased odds of periodontitis under the codominant and overdominant models (OR = 1.999; CI = 1.177–3.397; p = 0.01 and OR = 1.955; CI = 1.154–3.311; p = 0.013, respectively).