Histologic changes of tooth and periodontal tissues applying to contraction & intrusion force for the maxillary four incisors of dogs.
- Author:
Young Kuk KIM
1
;
Kyung Suk CHA
;
Jin Woo LEE
Author Information
1. Department of Orthodontics, College of Dentistry, Dankook University, Korea.
- Publication Type:Original Article
- Keywords:
Contraction UTA;
Intrusive force;
Cementum resorption;
Cacification
- MeSH:
Animals;
Dental Cementum;
Dogs*;
Incisor*;
Osteoblasts;
Periodontal Ligament;
Tooth*
- From:Korean Journal of Orthodontics
1999;29(5):535-549
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
The purposes of this study were to investigate the initial tissue changes on the teeth and surrounding tissues under contraction and intrusive force by contraction UTA. A control and experimental dogs, 10-months in age, were studied. Contraction and intrusive force(60gm) were applied at upper four incisors by contraction UTA. Experimental dogs were sacrificed at 2 weeks and 4weeks after force application, respectively. In this study, 2 experimental groups were designed by the duration of force applied(E1, E2). The specimens were taken around the upper first and second incisor in each groups and were prepared for the H-E and MT stain for light microscopic observation. From the results of the study, the following conclusions may be drown. : 1. In control group, the periodontal ligament width was constant from apical third to cervical third of the root and periodontal fiber arrangement was horizontal or oblique in cervical third, oblique in middle third and apical third. In alveolar bond, smooth appearance was shown with osteoblast. 2. In experimental group 1, in proportion to force was concentrated at labial middle third and apical third of root of the upper first and second incisors, root of these tooth tipped labially and intruded at a time. 3. In experimental group 2, periodontal ligament width and arrangement was similar to control and observed strong calcified response at the labial middle third of root. But, alveolar bond resorption and cementum resorption were as before seen at labial middle third and apical third of root force was concentrated.
