Researchers Identify New Clinical Response to Oral Inflammation

Investigators at the University of Washington (UW) School of Dentistry have identified a third type of oral inflammatory phenotype that exhibits a delayed response to bacterial accumulation. An inflammatory phenotype indicates how an individual reacts to accumulated plaque, thereby signalling if he or she is at greater risk of chronic periodontal inflammation. The study, “Human Variation in Gingival Inflammation,” is available in Proceedings of the National Academy of Sciences.

The team, which includes Richard Darveau, PhD, and Jeffrey McLean, PhD, of the UW School of Dentistry, studied individual responses to bioburden associated with periodontal disease. Prior to their discovery of the new oral inflammatory phenotype, there were two known oral inflammatory phenotypes: high (or strong) clinical response, and low clinical response. This newly identified “slow” phenotype displays a delayed strong inflammatory response to accumulated dental plaque. 

Researchers found the microbial community in individuals with the slow phenotype differs from those with either high or low phenotypes in that they contain a higher amount of healthy commensal Streptococcus species, which may influence the low pathogenic biofilm accumulation and transition to more pathogenic Gram-negative species. 

Additional findings revealed how host protective mechanisms use neutrophils to protect against tissue and bone damage during gingival inflammation. The researchers note this mechanism was apparent in all three phenotypes.

From Decisions in Dentistry. September 2021;7(9)6.