Aim: The objective of the study was to evaluate the effectiveness of scaling and root planing (SRP) and adjunctive chemotherapy (doxycycline hyclate, 20 mg) on gingival health, specific cytokines and glycemic control in diabetic subjects.
Methods: Three hundred and forty-six type 1 and 2 diabetic subjects were randomized into four test groups: (1) one session of SRP at the baseline visit and placebo tablets twice/day, started at the baseline visit, for 3 months, (2) one session of SRP at the baseline visit, and doxycycline hyclate (20 mg, twice/day) started at the baseline visit for 3 months, (3) two sessions of SRP, first at the baseline visit and second at the 6 months, with placebo tablets twice/day started at the baseline visit and 6-month visit, for 3 months at each visit, and (4) two sessions of SRP, first at the baseline visit and the second at the 6-month visit, and doxycycline hyclate 20 mg twice/day, started at the baseline visit and the 6-month visit, for 3 months
at each visit. Venous blood samples were obtained to evaluate TNF-a, IL-1a and glycated hemoglobin (HbA1c); dental measurements were also included.