FMSRP and PMSRP were equally effective in treating chronic periodontitis in subjects with type 2 diabetes, without significant improvements in the glycemic control at 3 and 6 months. Considering the periodontal therapy as a whole (FMSRP plus PMSRP), subjects with better-controlled diabetes exhibited a benefit in CAL at 6 months compared to subjects with poorly controlled disease.

RANKL/OPG ratios in untreated and treated periodontitis sites may be negatively influenced by poor glycemic control in subjects with type 2 diabetes.

These results indicate a predominance of pro-inflammatory T-helper type 1 (Th1)- or Th17-cytokines in sites of chronic periodontitis from type 2 diabetic subjects, according to their glycaemic control.

CP, but not type 2 diabetes mellitus, significantly affected the expressions of the evaluated genes related to the innate and adaptive immune responses.

The treatments did not differ with respect to clinical parameters, including the primary outcome variable (i.e. changes in clinical attachment level in deep pockets), for up to 12 months post-treatments.