title: [Changes of periodontal Ruffini's corpuscle induced by experimental tooth movement in rats].
abstract: OBJECTIVE
  To compare the ultra-microscopic changes of periodontal Ruffini's corpuscle induced by different patterns of tooth movement, and investigate the influence of different changes of the periodontal mechanical environment on the periodontal mechanoreceptor.
  
  
  METHODS
  Thirty-two eight-weeks-old SD rats were divided into control group (n = 4), none-extraction group (n = 12) and extraction group (n = 12), and none-extraction group and extraction group were further divided into three subgroups, namely 3 day and 14 day and 28 day. For control group, no intervention was performed. For none-extraction group and extraction group, the following interventions were conducted. In none-extraction group, the maxillary left and mandibular right third molars were moved distally. In extraction group, the maxillary left third molar was moved distally, and the bilateral mandibular third molars were extracted. The ultra-structures of periodontal Ruffini's corpuscle in the periodontal ligament of the distal root of the bilateral maxillary third molars were observed under the transmission electron microscope.
  
  
  RESULTS
  The ultra-structrural changes in the none-extraction group were mainly characterized by degeneration or abnormal distribution of mitochondria in the axon terminal, which were almost recovered at 28 d. In the extraction group, the changes were mainly characterized by deficiency or abnormal elongation of the Schwann sheath and were not recovered at 28 d.
  
  
  CONCLUSIONS
  The ultra-structures of periodontal Ruffini's corpuscle might be influenced by tooth movement and occlusal changes, and the mechanorecepting function of it might be affected by changes of the periodontal mechanical environment.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Liu
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Shibin
authors.initials: S
authors.lastname: Yu
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Huang
authors.affiliation: Email: mqwang@fmmu.edu.cn.
authors.forename: Meiqing
authors.initials: M
authors.lastname: Wang
mesh_terms: D000818:Animals; D008465:Mechanoreceptors / Q000502:physiology*; D008963:Molar; D008964:Molar, Third; D010513:Periodontal Ligament; D051381:Rats; D014087:Tooth Movement Techniques; D014092:Tooth Root