AbstractINTERLEUKIN-6 LEVELS IN GENERALIZED AND LOCALIZED AGGRESSIVE PERIODONTITIS PATIENTSBy Bindu Reddy, D.D.S.A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at the Virginia Commonwealth UniversityVirginia Commonwealth University, 2004Major Director: Joseph V. Califano, D.D.S., Ph.D.Associate Professor, Department of Periodontics Periodontitis is an inflammatory disease involving the supporting structures of the dentition. Many studies have shown that there is a relationship between periodontal disease, the presence of pro-inflammatory cytokines, and systemic disease such as cardiovascular disease and diabetes mellitus. The purpose of this study was to measure serum Interleukin-6 levels in generalized and localized aggressive periodontitis and non-periodontitis patients and look for relationships with measures of disease severity. We also examined variables known to have a relationship with IL-6. A total of 172 subjects, comprising three periodontal subgroups, non-periodontitis (NP=61), generalized aggressive periodontitis (GAP=77), and localized aggressive periodontitis (LAP= 34), had serum samples evaluated for IL-6 levels using a highly sensitive ELISA test. The IL-6 levels were compared with clinical and demographic data including age, race, gender, number of teeth, probing depth, attachment loss, bleeding index, plaque index, gingival index, cotinine levels, smoking status, and CRP levels. Using multiple regression analysis, smoking status (p=0.0015) was the only variable found to have a significant relationship with IL-6 levels for all three groups.