Antimicrobial Stewardship in Dentistry

By Paige Anderson, CRDH

Bacteria are the root of most oral diseases, and battling them is a huge part of our mission as oral healthcare providers. Beyond improving oral health, we now understand how oral bacteria can affect other organ systems and increase disease risks elsewhere in the body.

Antibiotics have been one of the most transformative tools in modern medicine, but their effectiveness is under increasing threat. The global rise in antibiotic resistance has been called a “silent pandemic,” and dentistry plays an important role in that story. We need to be incredibly cognizant of our role in the rise of antibiotic resistance and do what we can to avoid contributing to the problem.

Our Deepening Understanding of Antibiotic Resistance

Emerging research has deepened our understanding of how resistance genes emerge, persist, and spread within bacterial populations. This knowledge isn’t just academic for oral health professionals. It has direct implications for how we prescribe, prevent, and protect against infection.

Latent Antimicrobial Resistance Genes

Established antibiotic resistance genes (ARGs) are the clearly understood and identifiable types of resistance that are available in the literature. However, recent research has revealed that latent ARGs may represent an expansive potential for future resistance that can become activated at any time.

Latent ARGs are abundant, incredibly diverse, and largely unknown. They have been shown to move easily between environments and can pass horizontally among different bacterial species very quickly.

Horizontal Gene Transfer: A Ticking Time Bomb for Antibiotic Resistance

Genetics plays a crucial role in antibiotic resistance, and successful mutations are passed down quickly to future generations (meaning a matter of 20 minutes to a couple of hours). However, we now know that resistance mutations can also spread horizontally when different bacterial species swap genetic materials directly.

This multiplies the potential impact of ARGs exponentially. It also allows for the potential of reinfection with resistant strains after antibiotic therapy. Fortunately, gene editing technology may help us manage these risks.

Gene Editing: The Future of Antibiotics?

CRISPR is a gene-editing tool that was developed in the early 2000s. It utilizes a naturally occurring viral immune system to edit the genes of a target cell selectively. We can now use CRISPR to combat ARGs by programming an enzyme (Cas9) to selectively attack pathogens without harming commensal bacteria.

Amazingly, this strategy has proven effective in resensitizing bacteria to antibiotics or killing resistant bacteria outright. While CRISPR for antibiotic resistance has progressed by leaps and bounds in recent years, it is still largely experimental, so we need to continue combating antibiotic resistance where we can.

Dental Offices May Be the Perfect Storm for Antibiotic Resistance to Worsen

Unfortunately, dental offices themselves may provide ideal conditions for resistance to worsen. Frequent exposure to antiseptics and biocides (including antibacterial hand soap), often used in dental care and infection control, can also select for resistance. This setting doesn’t just make bacteria more resistant to antiseptics, but sometimes also to antibiotics.

Biofilms in the dental environment also pose a significant problem in the battle against antibiotic resistance. Dental unit water lines, dentures, and orthodontic appliances are three examples of reservoirs for potential ARGs in the dental office.

This is not to say that we should discontinue the use of biocides and antiseptics. Instead, we should emphasize mechanical and non-chemical methods for controlling bacteria both intra- and extraorally. Ultrasonic baths, autoclaves, and UV sanitizers can all serve as important adjuncts that don’t appear to contribute to the proliferation of ARGs.

Most importantly, we oral healthcare providers need to be incredibly mindful of how we use and prescribe antibiotics and antimicrobials for our patients.

Antibiotic Stewardship in Dentistry: Our Critical Role in the Battle

As an industry, dentistry accounts for about 10% of all antibiotic prescriptions in the U.S., making it the largest source of prescriptions of any specialty. Just as we need to be aware of how medications can affect our patients’ oral health, we need to be as mindful about how our use of antibiotics can affect general health for our patients and communities at large.

Several common practices highlight the importance of better antibiotic stewardship in dentistry:

• Prophylactic prescriptions after extractions and oral surgery. Prescribing antibiotics as a precaution rather than in response to an actual infection may be a major contributor to antibiotic resistance throughout the world. It’s critical to stay up to date on recommendations and include the potential for antibiotic resistance for all prescriptions.
• Empirical treatment of odontogenic infections. We frequently prescribe antibiotics for oral infections like abscesses without a culture or sensitivity testing, which can result in mismatched therapy and increased antibiotic resistance. Whenever possible, we should do what we can to prescribe the most effective antibiotic for the specific infection.
• Periodontal disease treatment. Antibiotics and antimicrobial agents are still frequently prescribed as adjuncts to periodontal therapy even though evidence for their long-term efficacy remains mixed. It’s important to understand that periodontal pathogens have unique survival strategies that can reduce the efficacy of antibiotics. For example, nutrient exchange in periodontal environments makes antibiotics targeting cell metabolism ineffective.
• Overuse of antimicrobial rinses. Recently, a class-action lawsuit alleged that antimicrobial mouthwashes are doing active harm and increasing the proliferation of antibiotic resistance. There is some evidence that many of our most frequently used rinses, like chlorhexidine, may accelerate the spread of resistance genes.

While antibiotic resistance in subgingival bacteria doesn’t appear to be a critical issue yet, projections conclude that it could become a major issue in the future. What is certain is that, in our efforts to control dysbiosis and improve our patients’ oral health, we need to be cautious about doing more harm than good.

What Should We Do? The Importance of Resistance-Informed Clinical Guidelines

Obviously, the dental field cannot avoid using antibiotics, antiseptics, or biocides. We need to treat infections and clean our offices. So what can we do?

Antibiotic resistance is one of the greatest public health challenges of our time, and we cannot afford to treat it as someone else’s problem. We need to embrace antimicrobial stewardship and implement resistance-informed clinical practices.

As an industry, we can improve our role in the fight against ARGs with:

• Better microbial diagnostics
• More personalized biological treatment planning
• Better use of targeted antibiotic therapies
• Adoption of non-antibiotic strategies
• Investment in the development of alternatives like photodynamic therapy

In general, oral healthcare providers should keep antibiotic resistance front of mind in their continuing education and clinical practice so that we can make evidence-based decisions to support community-wide efforts to keep all public health threats under control.

Author: Paige Anderson is a certified registered dental hygienist with eight years of clinical experience and an English degree. She blends her two areas of expertise to create resources for dental providers so they can change lives by giving their patients the highest possible standard of care.