Skip Navigation



The European Journal of Orthodontics Advance Access published online on March 26, 2008
The European Journal of Orthodontics, doi:10.1093/ejo/cjm133
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
30/3/320    most recent
cjm133v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Nakamura, Y.
Right arrow Articles by Kawasaki, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nakamura, Y.
Right arrow Articles by Kawasaki, K.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2008. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oxfordjournals.org.

Time-lapse observation of rat periodontal ligament during function and tooth movement, using microcomputed tomography

Yoshiki Nakamura*, Koji Noda*, Shinji Shimoda**, Takashi Oikawa*, Chihiro Arai*, Yoshiaki Nomura*** and Kenzo Kawasaki**

* Department of Orthodontics
** Department of Oral Anatomy, Tsurumi University School of Dental Medicine, Yokohama
*** Department of Oral Health, National Institute of Public Health, Wako-city, Japan

Address for correspondence Yoshiki Nakamura, Department of Orthodontics, Tsurumi University, 2-1-3, Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan, E-mail: nakamura-ys{at}tsurumi-u.ac.jp


  Abstract

The aim of this study was to observe the time-lapse changes in the rat periodontal ligament (PDL) during function and tooth movement. Under Nembutal anaesthesia, time-lapse changes in the thickness of the PDL of the first molars were investigated in five 12-week-old adolescent rats with microcomputed tomography. Three-dimensional (3D) images were reconstructed from the data. Histological observation was also performed, using undecalcified frozen sections of the maxillary first molar area.

The PDL appeared as a radiolucent furrow on the 3D images. A slight change in the thickness of the PDL was observed 1 hour after initiation of orthodontic force loading, which became significant after 6 hours, with the appearance of pressure–tension zones during the tooth movement. These changes were more significant 3 days after orthodontic loading.

Histological observation of the lingual cervical PDL (pressure zone) in nine 12- to 13-week-old rats demonstrated that the periodontal space had become narrow and the cellular elements appeared to be densely packed in the narrowed PDL 6 hours after orthodontic loading. Degeneration of tissues appeared 3 days after loading. Observation of the buccal cervical PDL (tension zone) demonstrated that the PDL was extended 6 hours after orthodontic force loading, and the extension continued for up to 3 days. Alkaline phosphatase activity was distributed in the PDL, except for the degenerating tissues in the pressure zone 3 days after loading.

The results suggest that the periodontal reaction was initiated within 6 hours after orthodontic force loading, which was related to the structural changes of the PDL. The changes probably induced an early response in individual cells of the PDL.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Eur J OrthodHome page
W. Hahn, J. Fialka-Fricke, H. Dathe, S. Fricke-Zech, A. Zapf, R. Gruber, D. Kubein-Meesenburg, and R. Sadat-Khonsari
Initial forces generated by three types of thermoplastic appliances on an upper central incisor during tipping
Eur J Orthod, December 1, 2009; 31(6): 625 - 631.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.