Though the study was small, the researchers said they found clear evidence in eight patients who developed pneumonia while in the hospital that had originated from their own dental plaque.

"This is the first study to establish unequivocally a link between dental hygiene and respiratory infection," said Dr. Ali El-Solh of the University at Buffalo in New York, who led the study.

El-Solh and colleagues expressed in the journal Chest that they tested 49 nursing home residents who were admitted to a nearby hospital with a high risk of pneumonia. They made molecular fingerprints of the bacteria found in each patient's mouth before he or she developed pneumonia.

Of the 49 patients, 28 had germs known to cause respiratory disease in their dental plaque samples and 21 did not.

The patients were watched closely for pneumonia. The researchers said 14 eventually developed pneumonia and 10 of them had started out with respiratory disease-causing germs in their teeth.

Tests of germs from the lungs showed the DNA matched the DNA of plaque germs in eight of the patients - more than half.

"These findings indicate that dental plaque is a reservoir of respiratory pathogens that can cause pneumonia in hospitalised institutionalised elders," said El-Solh.

So we should maintain clean teeth and dentures.

Source: http://www.reuters.com