title: Different antibiotic protocols in the treatment of severe chronic periodontitis: A 1-year randomized trial.
abstract: OBJECTIVE
  To evaluate the clinical effects of different dosages of metronidazole (MTZ) and durations of MTZ + amoxicillin (AMX) in the treatment of generalized chronic periodontitis (GChP).
  
  
  METHODS
  Subjects with severe GChP were randomly assigned to receive scaling and root planing (SRP)-only, or combined with 250 or 400 mg of MTZ + AMX (500 mg) thrice a day (TID), for 7 or 14 days. Subjects were monitored for 1 year.
  
  
  RESULTS
  One hundred and nine subjects were enrolled. At 1 year, 61.9% and 63.6% of the subjects receiving AMX + 250 or 400 mg of MTZ for 14 days, respectively, reached the clinical endpoint for treatment (≤4 sites with probing depth ≥5 mm), against 31.8% of those taking 250 or 400 mg of MTZ for 7 days (p < .05) and 13.6% of those receiving SRP-only (p < .05). Fourteen days of MTZ + AMX was the only significant predictor of subjects reaching the clinical endpoint at 1 year (OR, 5.26; 95% CI, 2.3-12.1, p = .0000). The frequency of adverse events did not differ among treatment groups (p > .05).
  
  
  CONCLUSIONS
  The adjunctive use of 400 or 250 mg of MTZ plus 500 mg of AMX/TID/14 days offers statistically significant and clinically relevant benefits over those achieved with SRP alone in the treatment of severe GChP. The added benefits of the 7-days regimen in this population were less evident. (ClinicalTrials.gov NCT02735395).
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Ivan
authors.initials: I
authors.lastname: Borges
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Faveri
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Luciene Cristina
authors.initials: LC
authors.lastname: Figueiredo
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Poliana Mendes
authors.initials: PM
authors.lastname: Duarte
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Belén
authors.initials: B
authors.lastname: Retamal-Valdes
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Sheyla Christinne Lira
authors.initials: SCL
authors.lastname: Montenegro
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Magda
authors.identifier: http://orcid.org/0000-0002-2293-3392
authors.initials: M
authors.lastname: Feres
mesh_terms: D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D055113:Chronic Periodontitis / Q000188:drug therapy / Q000382:microbiology / Q000628:therapy*; D003131:Combined Modality Therapy; D012534:Dental Scaling; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008875:Middle Aged; D010512:Periodontal Index; D011446:Prospective Studies; D016745:Root Planing; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole; D000658:Amoxicillin
keywords: antimicrobials; clinical outcomes; clinical studies; periodontal disease; periodontal tissues; treatment planning