Two-Year Randomized Clinical Trial of Adjunctive Minocycline Microspheres in Periodontal Maintenance

Purpose: The purpose of this study was to evaluate the effects of repeated scaling and root planing (SRP), with or without locally-delivered minocycline microspheres (MM) on residual pockets in patients undergoing periodontal maintenance (PMT).Methods: Patients on PMT were randomized into two groups for treatment of one posterior interproximal inflamed pocket (≥5 mm) with a history of bleeding on probing every 6 months: SRP plus MM (n=30) or exclusively SRP (n=30). Baseline and 24-month measurements included radiographic interproximal alveolar bone height, probing depths (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival crevicular fluid (GCF), and salivary interleukin (IL) - 1β, (24 month only). Results were analyzed for baseline data or change in measurements after 24 months of treatment between different treatment groups, as well as whether significant changes occurred after 24 months of treatment for each treatment group individually.Results: Alveolar bone height and GCF IL-1β remained stable over the 24 months. The SRP + MM and SRP groups each demonstrated reduced PD (0.8 ± 0.9 mm and 1.1 ±0.6 mm, respectively, p < 0.001 each), CAL (0.8 ± 0.9 mm and 1.0 ± 0.6 mm, respectively, p < 0.001 each) and BOP (55% and 48%, respectively, p = 0.001 each). However, there were no differences between groups over the 24-month study period.Conclusion: Scaling and root planning alone, of moderately inflamed periodontal pockets at 6-month intervals, produced stable interproximal alveolar bone height as well as sustained improvements in probing depths, clinical attachment level, bleeding on probing over 24 months; minocycline microspheres were not shown to enhance these results.