Objectives: To evaluate the efficacy of a slow release doxycycline gel (SRD) adjunctively administered to non-surgical therapy in subjects with recurrent or persistent periodontitis but acceptable oral hygiene during supportive periodontal care.
Material & methods: In this single blind, parallel group, multicentre study, 202 of 203 recruited periodontal maintenance subjects with recurrent or persistent periodontitis were randomly assigned to subgingival ultrasonic/sonic instrumentation (USI) with (test) or without (control) subsequent administration of SRD in all residual periodontal pockets ≥4 mm. Intergroup differences in probing depth, BOP reductions, treatment time, probing attachment levels were evaluated at 3, 6 and 12 months. The primary outcome was the inter-group difference in absolute change of probing pocket depth (PPD) 3, 6 and 12 months after intervention.
Results: At baseline, the two groups were comparable. At 3 months, the test group showed a significantly higher decrease in mean probing depth than the control group at 3 months (mean difference = 0.11 mm, 95% CI 0.03-0.19 mm, p = 0.003). Administration of SRD resulted in significantly greater odds of transition of bleeding pockets ≥5 mm to a category of non bleeding sites with PPD ≤4 mm at 3 and 6 months (O.R. = 1.4, 95% CI 1.2-1.8 at 3 months). At 6 months, SRD benefit was observed only in the deeper pockets. 7.5% of subjects (no significant difference between test and control) showed disease progression (attachment loss ≥2 mm) and were exited from the study. No difference in the incidence of adverse events was observed between groups.
Conclusion: The trial results show that topically administered SRD may provide short-term benefit in controlling inflammation and deep pockets in treated periodontal patients participating in a secondary prevention programme and able to maintain a satisfactory level of oral hygiene.
© 2012 John Wiley & Sons A/S.