Silver is a transition metal with a long history of clinical use. The earliest recorded clinical purpose of silver dates back to the Han Dynasty in China in 1500 B.C.E. In modern times, there has been considerable attention given to silver for its ability to promote oral health and support a healthy oral microbial environment.

Oral health support has become a global demand, regardless of age or gender. The severity and prevalence of dental caries and periodontal diseases have increased in the last few decades. For instance, the incidence of periodontal disease is estimated to affect 20% to 50% of the global population.

The potential antimicrobial properties of silver-containing agents have been investigated to support a healthy oral microbial environment. It is understood that certain bacterial strains contribute to the formation and progression of dental plaque, dental caries, and periodontal diseases, including Streptococcus mutans, Streptococcus sanguis, and Streptococcus salivarius.

In vitro research by Tran and colleagues concluded that silver-containing gel attenuated the biofilm formation of S. mutans, S. sanguis, and S. salivarius. Although further research is necessary, it is proposed that silver in gel form (such as that in toothpaste) may help attenuate plaque formation in the mouth.

In vitro research by Vila Domínguez and colleagues revealed that silver-containing agents mitigated the proliferation of gram-negative and gram-positive bacteria, including 270 strains of A. baumannii, P. aeruginosa, E. coli, S. aureus, S. epidermidis, and Enterococcus spp. Furthermore, silver-containing agents have been shown in vitro to attenuate the demineralization of enamel and dentin under acid or cariogenic biofilm challenges and support dental collagen matrix status, both of which may be clinically relevant to those with dental caries.

Current research has determined three potential methods on how silver promotes a healthy oral microbial environment. For one, silver may form pores and puncture the bacterial cell wall. Second, silver may enter the bacterial cell wall, inhibit cellular respiration, and disrupt metabolic pathways. Third, silver may disrupt bacterial cell DNA and its replication cycle.

Research suggests that silver-containing agents do not generate bacterial resistance, which may be relevant for longer-term clinical benefits. The diversity and health of the oral microbial environment may be associated with a lower risk of developing any problematic oral conditions. Adding silver-containing agents to standard dental treatment and oral hygiene practices may be clinically beneficial to support oral health and promote a healthy oral microbial environment.

By Danielle Moyer, MS, CNS, LDN