TNFSF11 and periodontitis: For comparison of serum proteins RANKL, OPG, and RANKL : OPG ratio and adjusted ΣMBL, periodontitis patients from the PEA analyses (n = 38) were divided into three groups based on medical diagnosis and the ADA classification of HbA1c levels of <5.7 (no diabetes), 5.7-<6.5 (prediabetes), and ≥6.5 (diabetes) to determine their bone resorptive status.