Mechanisms Underlying the Variation in Rate and Levels of Gingival Inflammatory Responses Among the Human Population

This study will employ the split-mouth Experimental Gingivitis model where healthy study participants are asked to abstain from oral hygiene on a select set of teeth (test teeth) for a period of 21 days. The study consists of 3 phases; Hygiene Phase (Day -14-0), Experimental Induction Phase (Day 0-21), and Resolution Phase (Day 21-35). Abstaining from oral hygiene on the test teeth will result in the natural accumulation and maturation of dental plaque (a bacterial biofilm) on the tooth surface which will in induce a host inflammatory response. By investigating the onset of microbially induced inflammation directly in humans using this highly utilized and well-described experimental gingivitis model, the research community are able to better understand the host-microbial interactions during the initiation, induction of host response, and resolution of mucosal inflammation at the molecular level. The investigators central hypothesis is based on our previous experimental gingivitis studies conducted here at the University of Washington Bamashmous et al. Human Variation in Gingival Inflammation PNAS 2021 and NCT03750955. The investigators hypothesize that specific clinical inflammatory response phenotypes (High, Low and Slow responders) are dependent upon both microbial factors regulating the subgingival plaque growth and maturation rate as well as host factors regulating the human gingival inflammatory mediator levels and type.