title: Differential cytokine expressions affect the severity of peri-implant disease.
abstract: OBJECTIVE
  This study assessed gene expression by quantitative polymerase chain reaction of inflammatory- [interleukin (IL)-12, tumor necrosis factor-alpha (TNF-alpha), IL-4, and IL-10] and osteoclastogenesis-related factors [receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG)] in sites exhibiting different severities of peri-implant disease.
  
  
  METHODS
  Peri-implant soft tissue biopsies (n=48) were harvested from healthy implant (HI), mucositis (MC), initial peri-implantitis (IP) and severe peri-implantitis (SP) sites.
  
  
  RESULTS
  IL-12 and TNF-alpha mRNA levels were higher in SP, followed by IP and MC (P <0.05). IL-4 was higher in HI, followed by MC, SP and IP (P <0.05). IL-10 was the lowest in HI, while no differences were detected among the diseased groups (P>0.05). OPG mRNA levels were higher in HI, followed by IP, SP and MC, whereas RANKL was increased as the peri-implantitis severity increased (P<0.05). The highest OPG/RANKL ratio was observed in HI and the lowest in SP (P<0.01).
  
  
  CONCLUSIONS
  These findings suggest that expressions of inflammatory- and osteoclastogenesis-related factors may play an important role in the onset and severity of the peri-implant diseases.
authors.affiliation: Department of Periodontics, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil. poliduarte@yahoo.com/pduarte@ung.br
authors.forename: Poliana Mendes
authors.initials: PM
authors.lastname: Duarte
authors.forename: Adriana Cutrim
authors.initials: AC
authors.lastname: de Mendonça
authors.forename: Maria Beatriz Braz
authors.initials: MB
authors.lastname: Máximo
authors.forename: Vanessa Renata
authors.initials: VR
authors.lastname: Santos
authors.forename: Marta Ferreira
authors.initials: MF
authors.lastname: Bastos
authors.forename: Francisco Humberto
authors.initials: FH
authors.lastname: Nociti Júnior
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002454:Cell Differentiation / Q000276:immunology; D016207:Cytokines / Q000276:immunology / Q000378:metabolism*; D015921:Dental Implants / Q000009:adverse effects*; D005260:Female; D005786:Gene Expression Regulation / Q000276:immunology / Q000502:physiology; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D018664:Interleukin-12 / Q000235:genetics / Q000378:metabolism; D015847:Interleukin-4 / Q000235:genetics / Q000378:metabolism; D007575:Jaw, Edentulous / Q000276:immunology / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D052016:Mucositis / Q000209:etiology / Q000276:immunology / Q000378:metabolism*; D010010:Osteoclasts / Q000276:immunology* / Q000378:metabolism; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism; D010518:Periodontitis / Q000209:etiology / Q000276:immunology / Q000378:metabolism*; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D012016:Reference Values; D012720:Severity of Illness Index; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D016207:Cytokines; D015921:Dental Implants; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D018664:Interleukin-12; D015847:Interleukin-4