Clinical and microbiological effects of systemic azithromycin in adjunct to nonsurgical periodontal therapy in treatment of Aggregatibacter actinomycetemcomitans associated periodontitis: a randomized placebo-controlled clinical trial

Objective: This study aimed to evaluate clinical and microbiological effects of systemic azithromycin (AZM) in adjunct to nonsurgical periodontal therapy (NSPT; or scaling root planing - SRP) in treatment of Aggregatibacter actinomycetemcomitans associated periodontitis (AAAP). Methods and materials: Seventy individuals with moderate to severe periodontitis and subgingival detection of A. actinomycetemcomitans were randomly allocated to two groups. Thirty-five individuals were allocated to full mouth SRP+AZM (500 mg oral delivery (OD) 9 3 days) while 35 individuals were allocated to SRP+ Placebo (OD 9 3 days) group. The clinical variables evaluated were probing depth (PD), clinical attachment level (CAL), gingival index (GI), plaque index (PI), and percent bleeding on probing sites (% BOP), while microbiologic variables included percentage of subjects positive for A. actinomycetemcomitans at baseline, 3, 6, and 12 months. a Results: The AZM group showed statisticlly significant reduction in mean PD (2.91 +/- 0.88 mm) as compared to placebo (1.51 +/- 0.98 mm) (P < 0.001), while CAL gain was significant in the AZM group (2.71 +/- 1.15 mm) as compared to the placebo group (1.71 +/- 1.29 mm) (P < 0.001). There was also a statistically significant reduction in the number of subjects positive for A. actinomycetemcomitans in the AZM group (P < 0.0001). Conclusion: Azithromycin was found to significantly improve the clinical and microbiological parameters in AAAP individuals.