Objective: To investigate the changes and clinical value of silent information regulator-1 (Sirtuin-1) and Sirtuin-6 in gingival crevicular fluid of chronic periodontitis (CP) patients with type 2 diabetes mellitus (T2DM). Methods: 147 CP patients with T2DM (T2DM group), 128 patients with simple CP (CP group) and 121 healthy subjects (control group) who were admitted to The 970 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army from March 2020 to March 2023 were selected. Patients in T2DM group were divided into mild group (n=49), moderate group (n=67) and severe group (n=31) according to the results of periodontal examination. The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid and the expression of nucleotide-binding oligomerization domain-like receptor hot protein domain subfamily member 3 (NLRP3) messenger ribonucleic acid (mRNA), programmed cell death-associated speck-like protein (ASC) mRNA and cysteine protease 1 (Caspase-1) mRNA in peripheral blood mononuclear cells were detected, and the periodontal clinical indexes were evaluated. The correlation between the levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid and periodontal clinical indicators, the expression of NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA in peripheral blood mononuclear cells in CP patients with T2DM were analyzed by Pearson correlation analysis. The value of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid in the diagnosis of CP combined with T2DM were analyzed by receiver operating characteristic (ROC) curve. Results: The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid in T2DM group were lower than those in CP group and control group (P<0.05), the bleeding index (SBI), probing depth (PD), gingival index (GI), plaque index (PLI), attachment loss (AL), NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA expression in peripheral blood mononuclear cells in T2DM group were higher than those in CP group and control group (P<0.05). The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid in CP group were lower than those in control group (P<0.05), the expressions of GI, SBI, PLI, PD, AL, NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA in peripheral blood mononuclear cells in CP group were higher than those in control group (P<0.05). The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid in severe group were lower than those in moderate group and mild group (P<0.05). The expression of GI, PLI, SBI, AL, PD, NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA in peripheral blood mononuclear cells in severe group were higher than those in moderate group and mild group (P<0.05). The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid in moderate group were lower than those in mild group (P<0.05), and the expressions of GI, PLI, SBI, AL, PD, NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA in peripheral blood mononuclear cells were higher than those in mild group (P<0.05). The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid of CP patients with T2DM were negatively correlated with GI, PLI, SBI, AL, PD, NLRP3 mRNA, ASC mRNA and Caspase-1 mRNA expression in peripheral blood mononuclear cells (P<0.05). The area under the curve (AUC) of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid for the diagnosis of CP combined with T2DM was 0.787 and 0.806 respectively, and the AUC of combined diagnosis was 0.912, which was higher than that of single diagnosis. Conclusion: The levels of Sirtuin-1 and Sirtuin-6 in gingival crevicular fluid of CP patients with T2DM are decrease, which are relate to the aggravation of periodontal tissue damage and the activation of NLRP3 inflammasome. Sirtuin-1 combine with Sirtuin-6 in gingival crevicular fluid has high value in the diagnosis of CP combine with T2DM. [ABSTRACT FROM AUTHOR]