title: Association of Functional Gene Polymorphism with Apical Periodontitis.
abstract: BACKGROUND
  To date, only a few studies have searched for relationships between genetic polymorphism and periapical microbial infection. Thus, the purpose of this systematic review was to evaluate the relationship between host modifying factors and their association with apical periodontitis.
  
  
  METHODS
  Two reviewers independently conducted a comprehensive literature search. The MEDLINE, Embase, Cochrane, and PubMed databases were searched. Additionally, the bibliographies of all relevant articles and textbooks were manually searched.
  
  
  RESULTS
  Eight articles were identified and included in this review. The results of the present review suggest that although some authors have reported that some biologic markers may play a role in apical periodontitis, others have not supported this association. Limitations were noted in the current studies by not judiciously matching selected case/control groups, balancing or adjusting for confounders (such as smoking, diabetes, and body mass index), using the Hardy-Weinberg Equilibrium, providing power calculation for a given sample size, correcting for false-positive (type I) error, or providing odds ratios with confidence intervals. The results of this review suggest polymorphism and biological modifiers, by which some individuals, if challenged by bacterial accumulations, may exhibit a more vigorous immunoinflammatory response, leading to apical periodontitis.
  
  
  CONCLUSIONS
  More research in this area is warranted to determine greater specificity in these possible interactions.
authors.affiliation: Department of Endodontics, Case School of Dental Medicine, Cleveland, Ohio. Electronic address: Axa53@case.edu.
authors.forename: Anita
authors.initials: A
authors.lastname: Aminoshariae
authors.affiliation: Department of Endodontics, University of Missouri-Kansas City School of Dentistry, Kansas City, Missouri.
authors.forename: James C
authors.initials: JC
authors.lastname: Kulild
mesh_terms: D015415:Biomarkers / Q000032:analysis; D020022:Genetic Predisposition to Disease; D006801:Humans; D010485:Periapical Periodontitis / Q000235:genetics*; D011110:Polymorphism, Genetic; D012307:Risk Factors
chemical_list: D015415:Biomarkers
keywords: Apical periodontitis; biologic markers; inflammation; polymorphism