RESUMO
OBJECTIVES: To determine the serum and gingival crevicular fluid (GCF) levels of resistin between individuals with chronic periodontitis (CP) and those without CP, and to evaluate the role of resistin in CP. MATERIALS AND METHODS: The addressed focused question was "Is there a difference in the resistin levels between individuals with CP and those without CP?" four electronic databases: Medline, PubMed (National Institutes of Health, Bethesda), EMBASE, and Science direct databases from 1977 up to March 2016 for appropriate articles addressing the focused question. EMBASE and Medline were accessed using OVID interface which facilitated simultaneous search of text words, MeSH or Emtree. Unpublished studies (gray literature) were identified by searching the Open-GRAY database and references of the included studies (cross referencing) were performed to obtain new studies. In-vitro studies, animal studies, studies that reported levels of other cytokines but not resistin, letters to the editor and review papers were excluded. RESULTS: Ten studies were included. Nine studies compared resistin levels between CP and periodontally healthy (H) individuals and reported higher mean serum and GCF levels of resistin in CP patients than the H controls. Two studies showed comparable resistin levels from GCF and serum between diabetes mellitus with CP (DMCP) and CP groups. Three studies included obese subjects and showed comparable serum and GCF resistin levels between obese subjects with CP (OBCP) and CP subjects. CONCLUSIONS: CP patients were presented with elevated levels of GCF or serum resistin as compared with H individuals. Resistin modulates inflammation in chronic periodontal disease and may be used as surrogate measure to identify subjects at risk for periodontitis. Resistin levels in patients with CP and systemic inflammatory disorders such as diabetes, obesity, or rheumatoid arthritis was not significantly higher than the levels in patients with only CP.