Three Pills, No Surgery: Azithromycin's Surprisingly Good Showing in Peri-implantitis
A dual-centre retrospective study finds that adjunctive systemic azithromycin added to non-surgical debridement produces meaningful pocket depth reduction and radiographic bone gain in peri-implantitis cases with intrabony defects. Here's what the numbers mean for your clinic.
Source Paper
Non-Surgical Treatment of Peri-implantitis Associated Intrabony Defects with the Use of Adjunctive Systemic Azithromycin: Clinical and Radiographic Outcomes of a Dual-Centre Retrospective Study
It turns out that in certain peri-implantitis cases presenting with intrabony defects, you can achieve meaningful radiographic bone gain without lifting a flap. Just debride, irrigate with chlorhexidine, hand the patient three days’ worth of azithromycin, and watch the defect angle widen on follow-up radiographs. The EFP does not currently recommend routine systemic antibiotics for peri-implantitis, which makes the findings of Leira et al.’s 2026 dual-centre retrospective paper all the more worth sitting with.
The Data Anchor
This retrospective analysis drew on records from two Spanish private clinics collected between March 2018 and October 2024. The final cohort comprised 28 patients and 36 implants, selected from an initial pool of 62 patients and 87 implants; 34 cases were excluded for missing data. Inclusion required confirmed peri-implantitis per Berglundh criteria (PPD ≥6 mm, BoP and/or suppuration, radiographic bone loss ≥3 mm) together with a radiographically confirmed intrabony defect exceeding 2 mm. The cohort skewed heavily toward mandibular posterior bone-level implants (77.8% mandible, 94.4% posterior); 71.4% had a prior history of periodontitis and 25% were current smokers. Mean follow-up was 22.9 months, ranging from 12 to 72 months.
The treatment protocol combined ultrasonic submucosal debridement, granulation tissue curettage, titanium brush surface decontamination where crown removal was feasible, and submucosal irrigation with 0.12% chlorhexidine digluconate. All participants received systemic azithromycin 500 mg once daily for three days.
“Within the limitations of this retrospective study, it can be concluded that non-surgical approach in combination with adjunctive systemic azithromycin may lead to mid- and long-term clinical and radiographic improvements at peri-implantitis associated intrabony lesions.” — Leira et al., 2026
Key Findings
- Two-thirds of treated implants achieved disease resolution (66.7% by EFP criteria), comparing favourably to the 54.4% and 56.3% reported in comparable series using surgical or metronidazole-based approaches.
- Mean probing pocket depth fell by 3.9 mm (from 7.5 mm at baseline to 3.5 mm), with 90.7% of sites reaching PPD below 5 mm at follow-up, compared to just 7.4% at baseline.
- Radiographic bone gain averaged 2.6 mm, with intrabony defect depth reduced by 2.2 mm and defect angle increasing by 26.8 degrees: a morphological shift consistent with genuine bone fill rather than soft tissue masking.
- Suppuration resolved completely across all 36 implants at final assessment, down from 72% of implants at baseline.
- Deeper baseline defects predicted better outcomes: baseline intrabony defect depth (r = 0.499, P = .002) and baseline PPD (r = 0.465, P = .004) both correlated significantly with bone fill, suggesting this protocol may be most rewarding in the cases that look most daunting.
- Under more restrictive resolution criteria (PPD below 5 mm with absent BoP and suppuration), the resolution rate dropped to 36.1%, a finding the authors report transparently and which usefully anchors expectations.
💡 The Clinical Bottom Line
For the implant presenting with a meaningful intrabony defect and probing depths in the 7 to 8 mm range, this paper provides reasonable evidence that a non-surgical session with adjunctive azithromycin is worth attempting before scheduling a surgical appointment, particularly where prosthetic access permits adequate surface decontamination. The correlation between baseline severity and bone gain is a genuinely useful clinical heuristic. What remains unresolved is whether azithromycin is doing the heavy lifting or whether meticulous debridement alone would produce comparable results; a placebo-controlled randomised trial is the obvious next step. Until then, this retrospective signal is worth knowing.
Dr Samuel Rosehill is a general dentist with a prosthodontic focus, practising at Ethical Dental in Coffs Harbour, NSW. He holds a BDSc (Hons) from the University of Queensland, an MBA, an MMktg, and an MClinDent in Fixed & Removable Prosthodontics (Distinction) from King’s College London.
Reference: Leira et al. “Non-Surgical Treatment of Peri-implantitis Associated Intrabony Defects with the Use of Adjunctive Systemic Azithromycin: Clinical and Radiographic Outcomes of a Dual-Centre Retrospective Study.” International Journal of Oral and Maxillofacial Implants, 2026. DOI: 10.11607/jomi.11673
Clinical Relevance
Non-surgical debridement plus a three-day azithromycin course resolved peri-implantitis in two-thirds of treated implants, with measurable radiographic bone gain at mean follow-up of nearly two years.
Disclosure: The author has no financial conflicts of interest related to the products or topics discussed in this review. This is an independent summary prepared for educational purposes.
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