The effect of systemic antibiotics in the treatment of patients with recurrent periodontitis

Background: Subjects with periodontal disease exist who either (i) respond poorly to initial mechanical therapy ("refractory" periodontitis) or (ii) fail to adopt adequate self-performed plaque control techniques and hence develop recurrent disease ("recurrent" periodontitis) at multiple sites during the supportive treatment phase (SPT). Various systemic antibiotic regimens have been tried as adjuncts to the mechanical (re-) treatment of such "difficult to treat"-patients. While most studies indicated a positive outcome of the adjunctive therapy, some clinical investigators reported that this additional measure provided little or no benefit. Aim: The aim of the present investigation was to study the more long term effect of adjunctive antibiotic therapy in the re-treatment of patients with a well defined history of recurrent periodontitis. Material and Methods: 17 subjects with recurrent advanced periodontal disease were, following a baseline examination, subjected to non-surgical therapy including the use of systemic antibiotics (amoxicillin and metronidazole). They were placed in a careful SPT program and re-examined after 1, 3 and 5 years. The examinations included both clinical and microbiological assessments. Results: it was demonstrated that in subjects with advanced and recurrent periodontitis, re-treatment including (i) comprehensive scaling and root planing (SRP), (ii) systemic administration of antibiotics and (iii) meticulous supragingival plaque control by both mechanical and chemical means established periodontal conditions that in the short term (3 years) and in the majority of subjects could be properly maintained by traditional SPT measures. Between 3 and 5 years, however, only 5 of the 17 subjects exhibited stable periodontal attachment levels. Conclusions: Some deep pockets and furcations were most likely inadequately instrumented during the active treatment phase. Microorganisms residing in biofilms left in such locations were probably not sufficiently affected by the 2 weeks of adjunctive antibiotic therapy. It is suggested that removal of certain subgingival deposits, therefore, may require surgical intervention.