Effectiveness of silver and iodine dressings on wound healing: a systematic review and meta-analysis

Objective: To evaluate the effects of silver and iodine dressings on healing time, healing rate, exudate amount, pain and anti-infective efficacy.

Design: Systematic review and meta-analysis.

Data sources: Databases including PubMed, Cochrane Library, Embase, Web of Science and CINAHL were surveyed up to May 2024.

Eligibility criteria: Randomised controlled trials comparing silver and iodine dressings on wound healing in humans.

Data extraction and synthesis: Evidence certainty was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Data extraction was done independently by two reviewers, with the risk of bias assessed using the Cochrane tool. Narrative synthesis was performed to evaluate the effects of silver and iodine dressings on healing time, healing rate, pain, exudate amount and anti-infective efficacy. Meta-analysis using Review Manager V.5.4 calculated standardised mean differences for healing time and relative risks for rate to quantify the impacts of the treatments.

Results: 17 studies (18 articles) were included. The meta-analysis indicated that silver dressings significantly reduced healing time compared with iodine dressings (SMD=-0.95, 95% CI -1.62 to -0.28, I²=92%, p=0.005, moderate-quality evidence), with no significant difference in enhancing healing rate (RR=1.29, 95% CI 0.90 to 1.85, I²=91%, p=0.16, low-quality evidence). Based on low-quality evidence, for exudate amount (3/17), 66.7% (2/3) of the studies favoured silver dressings over iodine in reducing exudate volume. For pain (7/17), 57.1% (4/7) of the studies reported no significant difference between silver and iodine dressings, while 42.9% (3/7) studies indicated superior pain relief with silver dressings. For anti-infective efficacy (11/13), 54.5% (6/11) of the studies showed equivalence between silver and iodine dressings, while 36.4% (4/11) suggested greater antibacterial efficacy for silver.

Conclusion: Silver dressings, demonstrating a comparable healing rate to iodine dressings, significantly reduce healing time, suggesting their potential as a superior adjunct in wound care.

Prospero registration number: CRD42020199602.