title: Changes of myelinated nerve and myelin basic protein expression in rats' periodontal ligaments after experimental tooth movement.
abstract: BACKGROUND
  Information about the effect of tooth movement on the myelinated nerve in the periodontal ligament is limited. In this study, we aimed to investigate what responses of the periodontal myelinated nerve can be evoked during experimental tooth movement.
  
  
  METHODS
  In experimental-I group, the maxillary left and mandibular right third molars were moved distally. In experimental-II group, the maxillary left third molar but not the right one was moved, and the bilateral mandibular third molars were extracted. The ultrastructures of the myelinated nerve in the periodontal ligament of the bilateral maxillary third molars were observed under a transmission electron microscope. The expression of myelin basic protein was evaluated by immunohistochemistry.
  
  
  RESULTS
  Degenerative ultrastructural changes of the myelinated nerve in the periodontal ligament were noticed mainly in the myelin sheath; these were observed earlier and were recoverable in the experimental-I group. In contrast, the ultrastructural changes of the myelinated nerve occurred mainly in the axons, were observed later, and were unrecoverable in the experimental-II group. A concomitant decrease of myelin basic protein expression was observed in both groups.
  
  
  CONCLUSIONS
  Both experimental tooth movement and occlusal changes accompanying it caused changes of the myelinated nerve in the periodontal ligament.
authors.affiliation: Department of Oral Anatomy and Physiology and TMD, School of Stomatology, Fourth Military Medical University, Xi'an, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.forename: Jing-Hui
authors.initials: JH
authors.lastname: Huang
authors.forename: Shi-Bin
authors.initials: SB
authors.lastname: Yu
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Liu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhong-Ying
authors.initials: ZY
authors.lastname: Qiu
authors.forename: Mei-Qing
authors.initials: MQ
authors.lastname: Wang
mesh_terms: D000818:Animals; D008928:Mitochondria / Q000473:pathology; D004676:Myelin Basic Protein / Q000096:biosynthesis*; D009410:Nerve Degeneration; D009413:Nerve Fibers, Myelinated / Q000502:physiology*; D010513:Periodontal Ligament / Q000294:innervation*; D051381:Rats; D014087:Tooth Movement Techniques
chemical_list: D004676:Myelin Basic Protein