Scaling and root planing and chlorhexidine mouthrinses in the treatment of chronic periodontitis: a randomized, placebo-controlled clinical trial

Objective: Evaluation of the clinical and microbiological effects of scaling and root planing (SRP) alone or in combination with 0.12% chlorhexidine (CHX) rinsing. Methods: A blind, placebo-controlled, parallel-design, randomized clinical trial was conducted in 29 subjects with chronic periodontitis. Subjects were assigned to two therapeutic groups: control (SRP+placebo) and test (SRP+CHX during and up to 42 days post-therapy). Clinical and microbiological [N-benzoyl-DL-arginine-2-naphthylamide (BANA test)] examinations were performed at baseline, 42 and 63 days post-therapy. Results: Initially, intermediate sites (4-6 mm) in the test group showed less plaque accumulation, gingival bleeding, bleeding on probing and a greater reduction in attachment level and probing depth (PD) at 63 days after treatment. The initially deep sites (>6 mm) in the CHX group also showed a better reduction in plaque accumulation and in PD compared with the control group. Both therapies led to a microbiological improvement; however, the test subjects showed a higher frequency of BANA-negative sites after treatment, which was sustained over time (p < 0.001). At 63 days, the control group presented 25 BANA-negative sites and 65 positive sites, and the test group 58 and 26, respectively. Conclusion: The combination of CHX rinses and SRP leads to clinical benefits and to a better reduction in BANA-positive species.