Saliva Dysfunction and Oral Microbial Changes among Systemic Lupus Erythematosus Patients with Dental Caries

Systemic lupus erythematosus (SLE) is a chronic autoimmune and inflammatory disease affecting multiorgans of human body. Independent studies show that SLE patients had higher caries prevalence compared to non-SLE individuals. However, the underlying mechanisms remain unclear. In present study, we enrolled SLE patients to explore potential factors contributing to the susceptibility of SLE patients to dental caries (such as oral hygiene, salivary function, and oral microbial community). Dental examination confirmed SLE patients were more vulnerable to caries. Although subjects in both groups announced similar oral hygiene habits, more dental plaque was found on tooth surfaces of SLE patents as revealed by plaque index. In addition, the salivary function was impaired in SLE group as salivary flow rate, buffering capacity, and pH were lower among SLE subjects compared to healthy controls. Importantly, disturbed microbial community with lower richness and diversity was observed in SLE group, as well as disequilibrium between acidogenic/aciduric pathogens and alkali-generating commensal bacteria. Our data suggest that SLE increases patients' sensitivity to dental caries through imposing stress to both host and oral microbes.