The butterfly effect: collateral damage and impacts of antimicrobial strategies on the oral microbiome

Abstract The oral cavity is a complex environment hosting diverse microbial biofilms on different surfaces, all immersed in saliva that enables recolonisation and spread. These microbial populations fluctuate with diet, hygiene, antimicrobials, and disease. While biofilm control measures aim to protect health, they may cause unintended effects, including antimicrobial resistance (AMR). Persistent resistant microbes reshape oral and systemic niches through ecological disruption and genetic adaptation, which may negatively impact human health.