Effect of Repeated Local Minocycline Applications on Clinical Parameters During Periodontal Maintenance Therapy

Objectives: The aim of this study was to examine the effect of repeated local application of minocycline microspheres (MM) on clinical periodontal parameters in patients diagnosed with moderate chronic periodontitis undergoing periodontal maintenance therapy (PMT). Specifically, this study evaluated probing depth (PD), bleeding on probing (BOP), and clinical attachment level (CAL) changes in one posterior interproximal experimental periodontitis site/patient at baseline, 6-month, and 12-month PMT recalls.
Methods: Subjects undergoing 6-month PMT for chronic moderate periodontitis at the UNMC College of Dentistry were randomized by gender and smoking status into two experimental site treatment groups: 1) root planing plus minocycline microspheres (RP + MM, n = 19) or root planing alone (RP, n = 20). Facial and lingual measures of PD, BOP and CAL were averaged for the experimental site interproximal area and for the adjacent interproximal area during normal PMT recalls at baseline, 6 months and 12 months. The changes in clinical parameters between the two groups and over time were evaluated by analysis of variance.
Results: Both groups showed statistically significant decreases in PD after baseline from 4.8 ± 0.1 mm at baseline to 4.1 ± 0.1 mm at 12 months (p < 0.0001). BOP decreased significantly over time for both groups (68 ± 6% at baseline, 36 ± 6% at 6 months, 32 ± 6% at 12 months; p < 0.0001). CAL also significantly improved over time in both groups (5.1 ± 0.1 mm at baseline, 4.6 ± 0.1 mm at 6 months, 4.4 ± 0.1 mm at 12 months, p <0 .0001). However, there were no significant differences in any clinical measures between RP + MM and RP.
Conclusions: Root planing inflamed periodontal pockets during PMT has a positive impact on reducing clinical signs of periodontitis, but addition of multiple MM applications does not enhance this effect.