title: Effect of tumor necrosis factor-alpha gene polymorphism on peri-implant bone loss following prosthetic reconstruction.
abstract: OBJECTIVE
  The present study investigates the association between a specific polymorphism in the tumor necrosis factor (TNF)-alpha gene, consisting of allele 2 of TNF-alpha-308, and peri-implant bone loss following prosthetic reconstruction.
  
  
  METHODS
  This case-control study included 36 patients (20 women, 16 men; mean age 46 years) who had used implant-supported prostheses for a minimum of 6 months and a maximum of 31 months. The patients were nonsmoking, white Caucasian Brazilians, in good general health, and were not receiving medication. In the case group, patients exhibited 1 or more implants with a diagnosis of peri-implant bone loss following prosthetic reconstruction; control patients had 1 or more healthy implants.
  
  
  RESULTS
  Polymorphism in the TNF-alpha gene, allele 2 of TNF-alpha, was not associated with an increased risk for peri-implant bone loss following prosthetic reconstruction (P=0.19; chi2=1.71; df=1), although 21.1% of the subjects carried allele in the control group 2, and 41.2% carried allele 2 in the case group.
  
  
  CONCLUSIONS
  Polymorphism in allele 2 of the TNF-alpha-308 gene is not associated with an increased risk for peri-implant bone loss following prosthetic reconstruction. However, further studies based on a greater number of patients are necessary.
authors.affiliation: Department of Periodontics, São Leopoldo Mandic Dental Research Institute, School of Dentistry, University of São Paulo, São Paulo, Brazil. patcury@yahoo.com
authors.forename: Patricia R
authors.initials: PR
authors.lastname: Cury
authors.forename: Julio César
authors.initials: JC
authors.lastname: Joly
authors.forename: Nívea
authors.initials: N
authors.lastname: Freitas
authors.forename: Wilson R
authors.initials: WR
authors.lastname: Sendyk
authors.forename: Fabio Daumas
authors.initials: FD
authors.lastname: Nunes
authors.forename: Ney S
authors.initials: NS
authors.lastname: de Araújo
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D016301:Alveolar Bone Loss / Q000209:etiology / Q000235:genetics*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003758:Dental Implantation, Endosseous / Q000009:adverse effects*; D015921:Dental Implants / Q000009:adverse effects*; D019094:Dental Prosthesis, Implant-Supported / Q000009:adverse effects*; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D015921:Dental Implants; D014409:Tumor Necrosis Factor-alpha