Could Better Oral Care in Hospitals Save Lives?
The largest randomized trial of its kind found that providing hospitalized patients with basic oral hygiene tools and education dramatically reduced the risk of hospital-acquired pneumonia.
A growing body of evidence continues to reinforce what dental hygienists have long understood: oral health is closely linked to overall health. Now, results from the Hospital-Acquired Pneumonia Prevention (HAPPEN) study suggest that something as simple as daily toothbrushing could significantly reduce the risk of hospital-acquired pneumonia among nonventilated patients.
The randomized controlled trial, one of the largest ever conducted on the topic, involved 8,870 patients across three Australian hospitals. Researchers sought to determine whether improving oral hygiene practices among hospitalized patients could reduce cases of nonventilator-associated hospital-acquired pneumonia (NV-HAP), a common and potentially deadly infection associated with longer hospital stays, higher healthcare costs, and increased mortality.
Patients in the intervention group received a toothbrush, toothpaste, oral health education materials, and access to online resources. Nurses also received oral care training and were encouraged to support and remind patients to brush and floss. As a result, daily oral care rates increased from 15.9% during control periods to 61.5% during intervention periods.
The impact was substantial. Researchers reported a 60% reduction in hospital-acquired pneumonia among patients exposed to the oral care intervention. The incidence of NV-HAP dropped from one case per 100 admission days in the control group to 0.41 cases per 100 admission days among patients who received the oral hygiene support program.
The findings highlight the role the oral microbiome may play in respiratory infections. Bacteria from the mouth can be aspirated into the lungs, particularly in medically compromised individuals. Hospitalization can alter the oral microbiome and create conditions that increase infection risk, making routine oral hygiene an important preventive measure.
The HAPPEN study findings were presented at the 2026 Congress of the European Society of Clinical Microbiology and Infectious Diseases. At the time of presentation, the results had not yet been published in a peer-reviewed journal, although the HAPPEN study protocol and analysis plans are publicly available.
