title: Association of interleukin 4 gene polymorphisms with dental implant loss.
abstract: OBJECTIVE
  The purpose of this study was to investigate the association between interleukin 4 (IL4) polymorphisms/haplotypes and dental implant loss.
  
  
  METHODS
  Two hundred and seventy eight (n = 278) unrelated patients were divided into 2 groups: (1) control group (C) composed of 186 individuals presenting at least 1 osseointegrated implant and (2) study group (S) composed of 94 individuals presenting at least 1 implant loss. After DNA collection, IL4 polymorphisms were investigated by polymerase chain reaction (PCR)-restriction fragment length polymorphism and for the variable number of tandem repeat (VNTR) only by PCR.
  
  
  RESULTS
  No association between alleles/genotypes of -590 (C/T) (P = 0.9704/P = 0.5992) and VNTR (P = 0.7155/P = 0.8789) polymorphisms and implant loss were found between the groups. Regarding +33 (C/T) polymorphism, no difference was found in genotype frequency (P = 0.1288), but the C allele was associated with implant loss (P = 0.0236, odds ratio = 1.61, 95% confidence interval = 1.1-2.4). Haplotype analysis showed no statistical differences between the groups.
  
  
  CONCLUSIONS
  The C allele of the +33 (C/T) polymorphism in the IL4 gene was associated with susceptibility to dental implant loss in Brazilians in the studied population.
authors.affiliation: *PhD Student, Department of Morphology, School of Dentistry at Araraquara, UNESP-São Paulo State University, Araraquara, Brazil. †Adjunct Professor, Department of Dentistry, University Federal of Sergipe, Lagarto, Brazil. ‡Adjunct Professor, University Federal of Sergipe, Department of Medicine, Lagarto, Sergipe, Brazil. §Full Professor, Center for Health and Biological Sciences, Pontifícia University Católica of Paraná, Curitiba, Brazil. ‖Adjunct Professor, Department of Morphology, School of Dentistry at Araraquara, UNESP-São Paulo State University, Araraquara, Brazil.
authors.forename: Suzane C
authors.initials: SC
authors.lastname: Pigossi
authors.forename: Fabiano
authors.initials: F
authors.lastname: Alvim-Pereira
authors.forename: Claudia C K
authors.initials: CC
authors.lastname: Alvim-Pereira
authors.forename: Paula C
authors.initials: PC
authors.lastname: Trevilatto
authors.forename: Raquel M
authors.initials: RM
authors.lastname: Scarel-Caminaga
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001938:Brazil; D015921:Dental Implants; D019232:Dental Restoration Failure; D005260:Female; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D015847:Interleukin-4 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D012307:Risk Factors
chemical_list: D015921:Dental Implants; C508598:IL4 protein, human; D015847:Interleukin-4