Efficacy of local drug delivery of 0.5% clarithromycin gel as an adjunct to non-surgical periodontal therapy in the treatment of current smokers with chronic periodontitis: a randomized controlled clinical trial

Background: The relationship between cigarette smoking and periodontal disease has been examined extensively. Local delivery of antimicrobials into periodontal pockets improves periodontal health. The present study is designed to investigate the adjunctive effects of subgingivally delivered 0.5% clarithromycin (CLM) as an adjunct to scaling and root planing for treating chronic periodontitis in smokers. Methods: Sixty‐one patients were randomized and categorized into two treatment groups: group 1, in which 31 individuals received scaling and root planing plus 0.5% CLM, and group 2, in which 30 individuals received scaling and root planing plus placebo gel. Clinical parameters were recorded at baseline and at 1, 3, and 6 months; they included plaque index (PI), modified sulcus bleeding index (mSBI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL). The mean concentration of 0.5% CLM in gingival crevicular fluid (GCF) was estimated by reverse‐phase high‐performance liquid chromatography. Results: Both therapies resulted in significant improvements. At the end of 6 months, the mean GI, PI, mSBI, PD, and CAL for the CLM group were 1.06 ± 0.28, 2.82 ± 0.64, 1.36 ± 0.24, 4.64 ± 0.63, and 4.90 ± 0.46, respectively, versus 1.38 ± 0.41, 3.22 ± 0.57, 1.44 ± 0.27, 6.07 ± 0.88, and 5.69 ± 0.46, respectively, for the placebo group. Using an individual‐based analysis, individuals in group 1 showed enhanced clinical outcome (P <0.05) over a period of 6 months compared with those in group 2. CLM was detected in GCF until a period of 7 weeks after the local drug delivery. Conclusion: Although both treatment strategies seemed to benefit the individuals, the adjunctive use of 0.5% CLM as a controlled drug delivery system enhanced the clinical outcome.