Short-term benefits of the adjunctive use of metronidazole plus amoxicillin in the microbial profile and in the clinical parameters of subjects with generalized aggressive periodontitis

J Clin Periodontol. 2010 Apr;37(4):353-65. doi: 10.1111/j.1600-051X.2010.01538.x.


Aim: The aim of this study was to evaluate the clinical and microbiological effects of scaling and root planing (SRP) alone or combined with metronidazole (MTZ) and amoxicillin (AMX) in the treatment of subjects with generalized aggressive periodontitis (GAgP).

Materials and methods: A double-blind, placebo-controlled, randomized clinical trial was conducted in 30 subjects receiving SRP alone or combined with MTZ (400 mg 3 x per day) and AMX (500 mg 3 x per day) for 14 days. Clinical and microbiological examinations were performed at baseline and 3 months post-SRP. Nine subgingival plaque samples per subject were analysed using checkerboard DNA-DNA hybridization.

Results: Subjects receiving MTZ and AMX showed the greatest improvements in the mean full-mouth probing depth and clinical attachment level and at initially intermediate and deep sites. The most beneficial changes in the microbial profile were also observed in the MTZ+AMX group, which showed the lowest proportions of the red complex as well as a significant decrease in the proportions of the orange complex after treatment. The antibiotic therapy also reduced the levels of Aggregatibacter actinomycetemcomitans at initially deep sites.

Conclusion: Subjects with GAgP significantly benefit from the adjunctive use of MTZ and AMX. The short-term advantages are observed in the clinical and microbiological parameters.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aggressive Periodontitis / microbiology
  • Aggressive Periodontitis / therapy*
  • Amoxicillin / therapeutic use*
  • Anti-Infective Agents / therapeutic use*
  • Bacteria / classification
  • Bacteria / drug effects
  • Bacteria / genetics
  • Combined Modality Therapy
  • DNA, Bacterial / analysis
  • Dental Plaque / microbiology
  • Dental Plaque / therapy
  • Dental Prophylaxis / methods*
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Metronidazole / therapeutic use*
  • Periodontal Index
  • Subgingival Curettage / methods
  • Time Factors
  • Treatment Outcome
  • Young Adult


  • Anti-Infective Agents
  • DNA, Bacterial
  • Metronidazole
  • Amoxicillin