There was a significant positive correlation between stage IV periodontitis and salivary IL-33 (rs = 0.531) in G4 (P-OSA), and there was a significant negative correlation between stage II periodontitis and GCF IL-1β (rs = −0.510, p < 0.05) in G2 (P). This evidence concerns the gene IL1B and obstructive sleep apnea syndrome.