Comparison of conventional periodontal maintenance versus scaling and root planing with subgingival minocycline

Background: Alternative regimens using subgingival antimicrobials compared to conventional periodontal maintenance (PM) may lead to more efficient protocols. The purpose of this study was to evaluate treatment time and clinical and radiographic outcomes in 2 periodontitis cohorts, one receiving conventional PM and the other receiving scaling and root planing (SRP) and multiple doses of subgingival minocycline. Methods: Moderate to advanced chronic periodontitis patients were concurrently treated with either: 1) scaling and root planing and 4 subgingival doses of minocycline microspheres in all greater than or equal to5 mm pockets over a 6-month period (RP/M; n = 24 patients); or 2) conventional 3-month periodontal maintenance (PM; n = 24 patients). Clinical and radiographic measurements, including probing depth (PD), clinical attachment level (CAL), and interproximal bone height (BH), were analyzed in 2 premolar/molar interproximal greater than or equal to5 mm pockets at baseline and 1 year using paired t tests, analysis of variance, chi-square analysis, and correlation coefficients. Results: Baseline clinical and radiographic data were Similar between RP/M and PM patients. Probing depths showed greater mean improvement in RP/M (0.9 +/- 0. 1 versus 0.4 +/- 0.1 mm, P = 0.02), with 25% of subjects in RP/M gaining greater than or equal to2 mm compared to 4.2% in PM (differences were statistically significant). The mean loss in bone height and percent subjects losing bone height were less in RP/M (0.05 +/- 0.05 mm; 12.5%) than PM (0.09 +/- 0.08 mm; 16.7%), but bone height differences were not statistically significant. A subset of RP/M molar furcation sites responded with similar PD reduction and no BH loss over 1 year. While cross-sectional RP/M data between CAL and BH, or PD and CAL were highly correlated, changes over 1 year were not correlated among any of these parameters. Conclusions: Scaling and root planing and subgingival minocycline in experimental sites took little time (<5 minutes/appointment), but resulted in more probing depth reduction and less frequent bone height loss than conventional periodontal maintenance.