Supportive periodontal therapy of furcation sites: non-surgical instrumentation with or without topical doxycycline

Dannewitz B, Lippert K, Lang NP, Tonetti MS, Eickholz P. Supportive periodontal therapy of furcation sites: non-surgical instrumentation with or without topical doxycycline. J Clin Periodontol 2009;36: 514-522. doi: 10.1111/j.1600-051X.2009.01414.x. Evaluation of the clinical effect of topical subgingival application of doxycycline gel adjunctively to scaling and root planing (SRP) at furcation sites during supportive periodontal therapy (SPT). In 39 SPT patients exhibiting at least four pockets >= 5 mm with bleeding on probing, SRP was rendered in all pockets >= 4 mm. Additionally, 14% doxycycline gel was applied subgingivally in 20 patients after random assignment (SRP&DOXY). Clinical parameters were assessed at baseline, 3, 6, and 12 months after therapy. Additional benefit of topical doxycycline was evaluated as a short-term (3 months) improvement of furcation involvement and influence on the frequency of re-instrumentation up to 12 months. A total of 323 furcation sites (class 0: 160; class I: 101; class II: 18; and class III: 44) were treated (SRP: 165, SRP&DOXY: 158). SRP&DOXY resulted in better improvement of furcation involvement than SRP alone 3 months after treatment (p=0.041). However, SRP&DOXY failed to show a significant difference between both groups in the number of re-instrumentations. Single subgingival application of doxycycline in addition to SRP had a short-term effect on furcation involvement. However, it failed to reduce the frequency of re-instrumentation up to 12 months at furcation sites.