Unclean dentures could raise pneumonia risk, a new study finds

People who wear false teeth and don’t clean them properly on a regular basis may put themselves at risk for pneumonia, according to researchers at Cardiff University in Wales, the UK. They took mouth, tongue and denture swabs from a group of hospital patients who had pneumonia and wore dentures and then compared the samples to those of denture-wearing patients in geriatric homes who did not have pneumonia.

They then analyzed the samples to identify the abundance and types of microbes present in the samples, specifically looking for microbes that could cause pneumonia and whether there were any significant differences between the two groups.

“We were expecting to see a difference but were surprised to see 20 times the number of potentially pneumonia-causing (Streptococcus pneumoniae) bacteria on dentures in people with pneumonia, compared to people without.” said Dr. Josh Twigg, the study’s lead author.

Uncovering the microbial landscape in dentures

They published their findings in the journal Medical Microbiology under the title “Compositional shifts within the denture-associated bacteriome in pneumonia - an analytical cross-sectional study.” 

Twigg and his team speculate that the dentures could play a role in causing pneumonia – that if they aren’t cleaned properly, they could provide a new surface where disease-causing microbes can colonize. People who wear dentures may then be inhaling saliva containing harmful microbes into their lungs where an infection can then take hold.

While fewer people have dentures because of the growing use of permanent (and more expensive) dental implants, about a fifth of the UK population still wear a full or partial removable denture. Despite advances in denture biomaterials, the majority of dentures are fabricated using polymethyl-methacrylate to which pathogens stick easily.

The potential role of dentures in pneumonia

While the study identifies a possible connection, Twigg stressed that the team couldn’t yet say that people got pneumonia because they were wearing dentures. “It’s just showing that there is an association there. This research is an early step in trying to unravel that puzzle of what exactly is the sequence of events.” 

While more research needs to take place, the public can still learn from the findings, he said.  “Our research has shown that there are potentially harmful microbial communities on dentures. It’s important to clean dentures thoroughly”. By attending the dentist regularly for check-ups and learning about the best way to look after your teeth, he hopes that more people will avoid needing to wear dentures entirely.