03/01/2025
The widespread use of chlorhexidine (CHX) as a gold-standard antiseptic in dentistry has significantly improved oral hygiene and disease prevention. However, recent studies reveal that prolonged and indiscriminate use of CHX might lead to bacterial resistance, with potential implications for clinical and public health practices. Resistance mechanisms include genetic mutations and efflux pumps, which allow bacteria to survive CHX treatment. Notably, these adaptations can also result in cross-resistance to antibiotics, compounding the challenges of antimicrobial resistance in healthcare.
Evidence of CHX resistance in oral bacteria, such as Streptococcus sanguinis and Porphyromonas gingivalis, is growing. Clinical isolates have demonstrated increased tolerance, and laboratory studies have identified persistent subpopulations within biofilms that withstand CHX's effects. Such phenomena suggest that the efficacy of CHX may be compromised over time, especially under conditions of sub-inhibitory exposure. While the prevalence of CHX resistance remains relatively low, the trend underscores the need for judicious use and further research into alternative antimicrobial strategies.
The emergence of resistance to CHX in oral bacteria warrants a reassessment of its extensive application in dental care. Further investigations should focus on resistance mechanisms, biofilm dynamics, and the implications for antibiotic cross-resistance. Emphasizing stewardship and exploring stabilized chlorine dioxide as a viable alternative could mitigate the risk of resistance development @ Citation1
Based on a detailed review of emerging research on chlorhexidine (CHX) resistance, it is evident that prolonged use of CHX in oral care contributes to selective pressure, fostering multidrug-resistant bacterial strains within dental plaque. Notable findings include the identification of CHX-resistant species such as Chryseobacterium culicis and Chryseobacterium indologenes, which exhibit both biofilm formation and cross-resistance to antibiotics. These insights emphasize the need to reassess the long-term safety of CHX-based products and explore alternative antimicrobial agents.
Both reviewed articles underline the critical importance of vigilant oral hygiene practices, balanced with the judicious use of antimicrobial agents to mitigate the risk of resistance evolution in oral microbiota. @ Citation2 &3
Citation1; Cieplik, F., Jakubovics, N. S., Buchalla, W., Maisch, T., Hellwig, E., & Al-Ahmad, A. (2019). Resistance Toward Chlorhexidine in Oral Bacteria – Is There Cause for Concern? Frontiers in Microbiology, 10(587). DOI:10.3389/fmicb.2019.00587.
Citation2; Saleem, H. G. M., Seers, C. A., Sabri, A. N., & Reynolds, E. C. (2016). Dental plaque bacteria with reduced susceptibility to chlorhexidine are multidrug resistant. BMC Microbiology, 16(214). DOI: 10.1186/s12866-016-0833-1.
Citation3; Cieplik, F., Jakubovics, N. S., Buchalla, W., Maisch, T., Hellwig, E., & Al-Ahmad, A. (2019). Resistance toward chlorhexidine in oral bacteria – is there cause for concern? Frontiers in Microbiology, 10(587). DOI: 10.3389/fmicb.2019.00587.
Comparison of Stabilized Chlorine Dioxide and Chlorhexidine:
Stabilized chlorine dioxide (SCD) offers an alternative with broad-spectrum antimicrobial activity and a lower propensity for resistance development. Unlike CHX, which primarily targets bacterial membranes, SCD generates reactive oxygen species, disrupting bacterial metabolism without inducing persistent mutations. Additionally, SCD is less likely to cause staining and taste alteration, common drawbacks of CHX. However, CHX remains a powerful agent for plaque control and gingivitis management, highlighting the need for a balanced approach in selecting oral antiseptics.
By Dr. Raman Asad
