If you’re a speech-language pathologist, you’re well aware of the culprits that cause morning breath and, if left unchecked, dental decay: the 1–10 trillion microorganisms that live in the oral cavity.

Scrape a cubic millimeter of those morning teeth with a fingernail, and you could collect up to 10 billion microorganisms, according to dentist Kenneth Shay, director of geriatric programs for the Office of Geriatrics and Extended Care at the U.S. Department of Veterans Affairs (see sources below).

Fortunately, the typical person’s oral microbiome maintains homeostasis—a healthy balance of chemicals and bacteria facilitated by saliva. But the situation can be quite different for patients staying in a health care institution, in which a heightened number of pathogenic microorganisms circulate. Some of these microorganisms are associated with serious diseases: A team led by (then) University of Pennsylvania dentistry researcher Jaya Sarin isolated 12 pathogenic microflora in the oral tracts of elderly people with pneumonia that were the same as those found in their lungs (see sources).

Particularly vulnerable to this pathogenic bacterial colonization are critically ill patients with dysphagia and prolonged hospitalizations, which may have included prolonged intubation—a population we as SLPs commonly treat in acute care and skilled nursing facilities. How can we better protect these patients? Much of it comes down to vigilant oral hygiene.

Combine any changes in salivary flow and chemistry with neglect of oral hygiene, and the threat of a disease like pneumonia heightens.

Saliva’s significance

Any discussion of oral health needs to include saliva, so let’s remind ourselves of its importance: When the amount and quality of saliva are fairly normal, the oral microbiome tends to maintain homeostasis. (Read more about this from SLP Nicole Rogus-Pulia.)

Among saliva’s many important functions are its aiding of:

Digestion. It begins the process of food breakdown (via amylase, lipase and proteolytic enzymes).

Taste. It helps break down and carry food chemicals to the taste buds on the tongue (the protein gustin is involved).

Lubrication. It moistens the bolus, oral cavity and esophageal tracts for swallowing (via mucin).

Warding off viral, bacterial and fungal colonization. If saliva’s delicate balance of anti-microbials and mucin is disrupted, bacterial adherence and overgrowth can occur.

Cleansing. Saliva continuously removes bacteria, plaque and microorganisms as we swallow. The higher the salivary flow, the better the cleansing action.

Protecting and repairing oral mucosa. Saliva keeps the surfaces of the oral cavity from drying out.

Dental remineralization. Protein and mineral concentrations in saliva maintain tooth enamel integrity.

Decay prevention. Saliva neutralizes acid (pH) levels, protecting tooth enamel against decay.

Sheltering of helpful microorganisms. Saliva fosters a healthy microbial community.

When certain of these salivary protections falter, the oral microbiome can lose its equilibrium. Combine any changes in salivary flow and chemistry with neglect of oral hygiene, and the threat of a disease like pneumonia heightens. Add the stress of critical illness to the mix, and you have the potential for a vicious, disease-generating cycle.

Disease-causing cycle

Here’s what can happen if the cycle takes hold: Poor oral hygiene will cause food debris and dental plaque to form a dense bacterial biofilm. The biofilm becomes too dense for the salivary immune properties to penetrate. As a result, bacteria thrive and produce acidic waste that lowers the salivary pH.

If there is low salivary flow or inadequate salivary chemical composition (due to, for example, medications, prior radiation or stress), the saliva’s buffering action against invasive organisms will fail. Once the tooth enamel is exposed to a pH of 5.5 or lower, enamel demineralization begins. This can lead to more decay and gum problems, creating more pockets to harbor even more bacteria.

Stress also takes a toll. Research led by Ella Naumova of the Witten/Herdecke University School of Dentistry (published in Scientific Reports in 2014), indicates that just an hour and a half of stress can alter salivary chemistry. Consider the amount of stress on a patient during an intensive care unit stay. The result could be changes in salivary chemistry and fewer immune factors to ward off bacteria, viruses and other toxins.

Just 1.5 hours of stress can alter salivary chemistry. Consider the amount of stress on a patient during an intensive care unit stay.

Toothbrush power

Given the high levels of stress and pathogens among our elderly patients in critical care, vigilant oral care is likely essential. What’s meant by vigilant care? Most obviously, it’s brushing a person’s teeth and using a mouthwash to rinse away debris. (Read more specific instructions on oral decontamination procedures.)

The best option is usually a suction toothbrush, as most of our patients are dependent for oral care, meaning they cannot clean their own teeth in any way. If suction is not required, then opt for an electric toothbrush for its better debridement power. Brushing and rinsing stimulate salivary flow and remove harmful bacterial that stick in the biofilm. As a result, we typically see improved quality of saliva and balance in the oral microbiome.

Some patients may show lower-than-normal production of saliva and need extra precautions. For example, some develop significant dry mouth due to side-effects from medications and to poor hydration. These patients may benefit from application of an artificial saliva substitute before meals. This substitute can be easily sprayed in the mouth or applied to the tongue, gums, cheeks and palate with a swab after thorough oral cleaning.

Providing essential oral care is not a new finding. As far back as 1978, Stanley Schwartz and colleagues from the University of Pittsburgh found that harmful gram-negative bacteria colonized the trachea in only three days of endotracheal intubation. These pathogenic microorganisms can take a trip from the mouth to the lungs along the endotracheal tube, possibly causing aspiration pneumonia.

It can take just 48 hours of hospitalization for bacteria to change from gram-positive streptococci to gram-negative pathogens, according to Kenneth Shay of the VA. The risk is the same for people with natural teeth, dentures and even edentulous status—bacterial biofilm can heavily coat their tongues and palates. In a 2015 study of frail elderly patients with oropharyngeal dysphagia, the highest bacterial load appeared on the teeth and tongue, as well as in the saliva. The research was conducted by Omar Ortega of Consorci Sanitari del Maresme in Mataró, Spain, and colleagues.

Has oral care improved at your medical facility in the past 10 years? If not, you might notify your patient safety team about the marked preventive benefits of improved oral hygiene.

The forgotten mouth

Unfortunately, despite all the research findings on oral health’s role in pneumonia prevention, medical staff don’t always consider toothbrushing a priority. Many treat oral care as a “comfort measure with low priority and utilize foam swabs rather than toothbrushes,” write researchers Amelia Ross and Janet Crumpler of Wake Forest University Baptist Medical Center. Busy hospital routines may cause staff to choose foam swabs with no toothpaste or mouthwash over toothbrushes. However, foam swabs are not as successful at removing plaques and biofilm that harbor pathogenic microorganisms.

The Ross and Crumpler research points to benefits of more rigorous oral care. In their study, a nurse training program on the benefits of tooth-brushing over foam swabs led to a 50-percent reduction in ventilator-acquired pneumonia rates among patients.

Given such findings, why might hospital staff fail to provide adequate oral care? The common barriers to providing quality oral care include:

Inadequate knowledge of how to assess and provide effective oral care.

Lack of appropriate supplies, such as suction toothbrushes.

Busy hospital routines and lower prioritization of effective oral care.

The simple prevention technique of brushing costs pennies a day against the cost of treating pneumonia. The U.S. Centers for Disease Control and Prevention (CDC) estimates there were 157,500 health care-associated pneumonias in the country in 2011. According to the CDC, the average extra cost of treating one case of hospital-acquired pneumonia is $22,875. So the total cost of treating all of those pneumonias in 2011 equals more than $3 billion!

Busy hospital routines may cause staff to choose foam swabs with no toothpaste or mouthwash over toothbrushes. However, foam swabs are not as successful at removing plaques and biofilm.

What can the SLP do?

Has oral care improved at your medical facility in the past 10 years? If not, you might notify your patient safety team about the marked preventive benefits of improved oral hygiene.

Point out that staff assist dependent older patients with regular toileting schedules, so the same can be done with an oral care routine—every four hours, for example, or at least once a shift.

You can also factor increased consideration of oral hygiene into your own work with older patients with dysphagia.

Consider oral pathogens to be a key piece of your patient’s aspiration pneumonia puzzle.

Identify by means of your own thorough evaluation when oral hygiene and altered saliva are potential pneumonia risks. Discuss your findings with the medical team.

Advocate for oral decontamination and restoring a healthy oral microbiome to 1) improve swallowing efficiency (as improved slippery saliva can decrease residue), 2) prevent bacterial aspiration pneumonia, and 3) improve overall health, comfort and quality of life.

With thorough attention to the whole patient, we can boost patient safety. If a person has a triple problem—compromised immunity, poor oral hygiene and no one performing oral decontamination—aspiration puts them at increased risk for pneumonia. Our best tool for disease prevention in patients with dysphagia is a holistic approach to care.

Sources Naumova, E. A., Sandulescu, T., Bochnig, C., Khatib, P. A., Lee, W.-K., Zimmer, S., & Arnold, W. H. (2014). Dynamic changes in saliva after acute mental stress. Scientific Reports , 4 , 4884. doi.org/10.1038/srep04884 CrossrefGoogle Scholar , 4884. doi.org/10.1038/srep04884

Ortega, O., Sakwinska, O., Combremont, S., Berger, B., Sauser, J., Parra, C., … Clavé, P. (2015). High prevalence of colonization of oral cavity by respiratory pathogens in frail older patients with oropharyngeal dysphagia. Neurogastroenterology & Motility , 27 (12), 1804–1816. doi:10.1111/nmo.12690 CrossrefGoogle Scholar (12), 1804–1816. doi:10.1111/nmo.12690

Ross, A., & Crumpler, J. (2007). The impact of an evidence-based practice education program on the role of oral care in the prevention of ventilator-associated pneumonia. Intensive and Critical Care Nursing , 23 (3), 132–136. CrossrefGoogle Scholar (3), 132–136.

Schwartz, S. N., Dowling, J. N., Benkovic, C., Dequittner-Buchanan, M., Prostko, T., & Yee, R. B. (1978). Sources of gram-negative bacilli colonizing the tracheae of intubated patients. Journal of Infectious Diseases , 138 , 227–231. CrossrefGoogle Scholar , 227–231.

Sarin, J., Balasubramaniam, R., Corcoran, A. M., Laudenbach, J. M., & Stoopler, E.T. (2008). Reducing the risk of aspiration pneumonia among elderly patients in long-term care facilities through oral health interventions. Journal of the American Medical Directors Association , 9 , 128–135. CrossrefGoogle Scholar , 128–135.

Shay, K. (2014, April). Dental perspectives on aspiration pneumonia causes and management. Session at the ASHA Health Care and Business Institute , Las Vegas, Nevada . Google Scholar

Author Notes