Systemic antibiotic therapy as an adjunct to non-surgical peri-implantitis treatment: A single-blind RCT

J Clin Periodontol. 2021 Jul;48(7):996-1006. doi: 10.1111/jcpe.13464. Epub 2021 May 3.


Aim: The aim of this single-blind RCT was to evaluate the adjunctive clinical and microbiological effect of systemic amoxicillin (AMX) plus metronidazole (MTZ) to non-surgical treatment of peri-implantitis.

Material and methods: Patients (N = 62) with peri-implantitis were randomly assigned to receive full-mouth mechanical debridement and decontamination and use of chlorhexidine (control group) or combined with antibiotic therapy of AMX/MTZ (test group). Primary outcome was change in bleeding score from baseline (T0 ) to 3-month follow-up (T3 ). Secondary parameters were plaque, suppuration, PPD, CAL, bone level, microbiology, adverse events and need for additional surgery. Data were analysed with linear multiple regression analysis.

Results: 57 patients with 122 implants completed 3-month follow-up. Both groups showed major clinical improvements at T3 in both peri-implant and periodontal parameters. However, no significant differences were observed between both groups for any of the primary or secondary parameters.

Conclusions: Systemic antibiotic therapy of AMX/MTZ does not improve clinical and microbiological outcomes of non-surgical peri-implantitis treatment and should not be routinely recommended. Although complete disease resolution may be difficult to achieve, meticulously performed full-mouth non-surgical treatment, achieving a high level of daily oral hygiene and healthy periodontal tissues, can significantly improve the starting position of the subsequent (surgical) peri-implantitis treatment phase.

Keywords: dental implants; non-surgical therapy; peri-implantitis; periodontal disease; systemic antibiotics.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Amoxicillin / therapeutic use
  • Anti-Bacterial Agents / therapeutic use
  • Dental Implants*
  • Humans
  • Peri-Implantitis* / drug therapy
  • Single-Blind Method
  • Treatment Outcome


  • Anti-Bacterial Agents
  • Dental Implants
  • Amoxicillin