Sleeping in dentures may increase the risk of pneumonia, according to a recent study.

Japanese researchers found that sleeping in dentures doubles the risk of pneumonia in the elderly. Poor oral health and hygiene are increasingly recognized as major risk factors for pneumonia among elders 85 years of age or older.

At baseline, 524 randomly selected seniors were examined for oral health status and oral hygiene behaviors as well as medical assessment, including blood chemistry analysis, and followed up annually until first hospitalization for or death from pneumonia. Over a three-year follow-up period, 48 events associated with pneumonia were identified (20 deaths and 28 acute hospitalizations). Among 453 denture wearers, 186 (40.8%) who wore their dentures during sleep, were at higher risk for pneumonia than those who removed their dentures at night.

In a multivariate Cox model, both perceived swallowing difficulties and overnight denture wearing were independently associated with approximately 2.3-fold higher risk of the incidence of pneumonia, which was comparable with the high risk attributable to cognitive impairment, history of stroke and respiratory disease. In addition, those who wore dentures while sleeping were more likely to have tongue and denture plaque, gum inflammation, positive culture for Candida albicans, and higher levels of circulating interleukin-6 as compared to their counterparts.

This study provides empirical evidence that denture wearing during sleep is associated not only with oral inflammatory and microbial burden but also with incident pneumonia, suggesting potential implications of oral hygiene programs for pneumonia prevention in the community.

The findings were published in the Journal of Dental Research.