Background: This meta-analysis aimed to compare the efficacy of antimicrobial photodynamic therapy (aPDT) with systemic doxycycline, as adjunctive treatments to scaling and root planing (SRP) for treating periodontitis in patients with type 2 diabetes mellitus (T2DM). Methods: A search across electronic databases including PubMed, Scopus, CENTRAL, OVID EMBASE and OVID MEDLINE was carried out to identify relevant randomised controlled trials (RCTs), comparing aPDT or doxycycline combined with SRP, versus SRP alone. Data were pooled using random-effects models and indirect comparisons were retrieved using the Chi2 test for subgroup differences, to assess the impact of these treatments on glycated haemoglobin (HbA1c), probing depth (PD), and clinical attachment level (CAL). Results: Eight RCTs were included. aPDT with SRP showed a significant reduction in probing depth compared to doxycycline (MD = -0.55 mm, 95% CI: -1.03 to -0.07; p = 0.02). A significant difference between the two subgroups was found (p = 0.04), suggesting aPDT was more effective. No significant differences were found for HbA1c or CAL between the two interventions. Conclusions: The findings suggest that aPDT may offer greater benefits for the treatment of periodontitis in T2DM patients. This suggests that aPDT could potentially be a non-antibiotic alternative to doxycycline. However, as neither treatment influenced HbA1c, clinicians should not rely on periodontal therapy for glycaemic control.

The authors have declared no competing interest.

This study did not receive any funding

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The source data were widely available before carrying out the study. The data used in the meta analysis were extracted from eight RCTs available on various electronic databases including PubMed Scopus CENTRAL Embase and MEDLINE.

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