Chronic Periodontitis and RANKL/OPG Ratio in Peri-Implant Mucosae Inflammation

Braz Dent J. 2018 Jan-Feb;29(1):14-22. doi: 10.1590/0103-6440201801241.

Abstract

tHistory of chronic periodontitis (CP) is a risk factor for oseointegration failure. The osteoclastogenesis system (RANK, RANKL and OPG) is critical for bone homeostatic control. We investigated the levels of OPG and RANKL in peri-implant tissues from volunteers with and without a history of CP and their association with mucosae inflammation. This is a single-blind case-contro study. Diagnosis of a history of CP and peri-implant examination was performed on 46 volunteers, divided into control (without history of CP, n=26) and CP group (with history of CP, n=20). Gingival biopsies were harvested during implant exposure. Quantitative PCR evaluated OPG/RANKL mRNA expressions. OPG and RANKL proteins were analyzed by western blot and immunohistochemistry assay. The chi-square test analyzed the significance of nominal variables between groups while continuous variables were analyzed by T-test or Mann-Whitney test, after Shapiro-Wilk test evaluation. The 2-ΔΔCT Livak method calculation evaluated the gene expression. Values of p<0.05 were considered statistically significant. Volunteers with CP history had 23 times higher chance of developing mucosae inflammation. High mucosae levels of RANKL (p=0.04) and RANKL/OPG (p=0.001) mRNA expressions were observed in CP group. CP volunteers showed increased RANKL protein levels in opposition to decreased OPG expression. Even without active periodontitis, volunteers with a history of CP had elevated gingival levels of RANKL/OPG and higher correlation with peri-implant mucosae inflammation and implant loss.

MeSH terms

  • Aged
  • Blotting, Western
  • Chronic Periodontitis / metabolism*
  • Chronic Periodontitis / pathology
  • Dental Implants*
  • Female
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Mouth Mucosa / pathology*
  • Osteoprotegerin / genetics
  • Osteoprotegerin / metabolism*
  • Polymerase Chain Reaction
  • RANK Ligand / genetics
  • RANK Ligand / metabolism*
  • RNA, Messenger / genetics

Substances

  • Dental Implants
  • Osteoprotegerin
  • RANK Ligand
  • RNA, Messenger
  • TNFRSF11B protein, human
  • TNFSF11 protein, human