Non-surgical periodontal therapy with and without subgingival minocycline administration in patients with poorly controlled type II diabetes: a randomized controlled clinical trial

The aim of this study was to evaluate changes in clinical parameters and levels of inflammatory biomarkers in plasma in periodontal patients with poorly controlled type 2 diabetes mellitus (T2DM) after non-surgical periodontal therapy. Twenty-eight poorly controlled T2DM patients were randomly assigned to treatment with scaling and root planning (SRP) and SRP + subgingival minocycline administration. Clinical parameters, including the probing depth (PD), bleeding on probing (BOP), plaque score (PS), clinical attachment level (CAL), and plasma interleukin (IL)-6, soluble receptor of advanced glycation end products (sRAGE), chronic reactive protein (CRP), and hemoglobin A1c (HbA1c) were measured before and after a 6-month treatment period. Significant changes in PD, BOP, PS, and CAL were found in both groups. The latent growth curve model showed an overall reduction in the log HbA1c level in the SRP group (−0.082, p = 0.033). Small changes in the log sRAGE level and log CRP level in plasma were found in both groups. IL-6 in the plasma increased in the SRP group, but slightly decreased in the SRP+minocycline group (0.469 pg/ml, p = 0.172). Non-surgical periodontal therapy with or without subgingival minocycline application may achieve significant periodontal improvement and moderate improvement in HbA1c, but had no significant effect on plasma levels of IL-6, CRP, or sRAGE in patients with poorly controlled T2DM. For patients with both periodontal diseases and diabetes, non-surgical periodontal treatments may be helpful in their diabetic control.