A six-month comparison of three periodontal local antimicrobial therapies in persistent periodontal pockets

Background: Currently, several local antimicrobial delivery systems are ava ilable to periodontists. The aim of this 6-month follow-up parallel study w as to evaluate the efficacy of three commercially available local delivery systems as adjuncts to scaling and root planing in the treatment of sites w ith persistent periodontal lesions. Methods: Seventy-nine patients with 4 pockets greater than or equal to 5 mm and bleeding on probing and/or suppuration were randomized into 4 treatmen t groups which included: scaling and root planing alone (S) (20 patients), or in conjunction with the application of 25% tetracycline fibers (S+Tet) ( 19 patients), or 2% minocycline gel (S+Min) (21 patients), or 25% metronida zole gel (S+Met) (19 patients). Clinical measurements were taken at baselin e, 6 weeks, 3 months, and 6 months after antimicrobial application. Treatme nts were applied using the distributors' recommended protocols. Results: All 4 therapies resulted in significant improvements from baseline in probing depth, attachment level, bleeding on probing, and the Modified Gingival Index (MGI) scores. The improvements in clinical parameters were g reater in all 3 adjunctive treatment groups than scaling and root planing a lone. The mean probing depth reductions at 6 months were: scaling + tetracy cline = 1.38 mm; scaling + metronidazole = 0.93 mm; scaling + minocycline = 1.10 mm; and scaling alone = 0.71 mm. The probing depth reduction at all t ime points was significantly greater in the scaling plus tetracycline fiber group than the scaling and root planing alone group (P<0.01). There was al so a significant improvement for scaling plus tetracycline fiber applicatio n over scaling and metronidazole at both 6 weeks and 3 months, although thi s did not remain significant at the 6-month visit. While the frequency of s ites with suppuration was markedly reduced following all antimicrobial trea tments, the most effective reductions were seen in the scaling plus tetracy cline fiber group, followed by the minocycline group. Conclusions: Although all 3 locally applied antimicrobial systems seem to o ffer some benefit over scaling and root planing alone, a treatment regimen of scaling and root planing plus tetracycline fiber placement gave the grea test reduction in probing depth over the 6 months after treatment.