title: [Expression of receptor activator of NF-κB ligand and osteoprotegerin in peri-implant tissues during unloading period].
abstract: OBJECTIVE
  To observe the expression of receptor activator of NF-κB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) during unloading period of dental implants.
  
  
  METHODS
  An animal model of dental implants was established in Beagle dogs. Bone remodeling was tested at 3, 7, 15, 30, 60 and 90 days after the placement of implants. RANKL and OPG mRNA expression were quantified by real-time PCR. Then mandibular bones were resected and some sections were observed.
  
  
  RESULTS
  The most prominent period of bone remodeling occurred at 7 day after the placement of implants (OPG/RANKL mRNA, 2.15 ± 0.1). The expression of RANKL and OPG increased in a time-dependent manner in both soft and hard tissue. After 7 days they gradually decreased.
  
  
  CONCLUSIONS
  Both OPG and RANKL were expressed in peri-implant tissues, and the changing tendency of RANKL and OPGmRNA was consistent with the change of bone remodeling. The active stage for bone remodelling in peri-implant tissues during unloading period is about 7 days after implantation.
authors.affiliation: Department of Dental Implantation Center, Yantai Stomatological Hospital, Yantai Shandong 264008, China.
authors.forename: Wen-juan
authors.initials: WJ
authors.lastname: Zhou
authors.forename: Zhong-hao
authors.initials: ZH
authors.lastname: Liu
authors.forename: Peng-jie
authors.initials: PJ
authors.lastname: Hao
authors.forename: Sheng
authors.initials: S
authors.lastname: Xu
authors.forename: Ai-jie
authors.initials: AJ
authors.lastname: Sun
authors.forename: Zhuo-rui
authors.initials: ZR
authors.lastname: Li
mesh_terms: D000818:Animals; D016723:Bone Remodeling / Q000235:genetics*; D003757:Dental Implantation; D004285:Dogs; D008297:Male; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism*; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger