Adaptive alterations of elastic fibers in the bilaminar zone of rabbit temporomandibular joint following disc displacement.
OBJECTIVE
To study the adaptive alterations of elastic fibers in the bilaminar zone (BZ) of rabbit temporomandibular joint (TMJ) following disc displacement.


METHODS
Twenty-eight Japanese white rabbits were used in this study. The right temporomandibular joints of 20 of 28 rabbits were subjected to the surgical procedure of anterior disc displacement (ADD). Four rabbits in the surgical group were sacrificed at 2, 4, 6, 8 and 12 weeks after operation. Their temporomandibular joints were studied histochemically.


RESULTS
Elastic fibers were reduced in number and ran irregularly in the superior lamina of BZ from ADD rabbits. The jungly elastic fibers (EFs) could still be seen at 2 weeks after operation. At 4 weeks, the number of EFs decreased significantly; EFs lost their jungly arrangement and were shaped like rough dots, of which the arrangement and the lengths were different. Six weeks after operation, many EFs were replaced by distorted, uneven, non-oriented fine EFs, distributed unevenly and some thick or fine EFs that ran irregularly. The number of EFs decreased further and their arrangement was more deranged at 8 weeks. At 10 and 12 weeks, EFs in the superior lamina of BZ were similar to those at 8 weeks.


CONCLUSIONS
Our results show that EFs lost their function as well as their distribution and arrangement after disc displacement.
Gu
Zhiyuan
Z
Department of Oral and Maxillofacial Surgery, Hospital of Stomatology, Collage of Medicine, Zhejiang University, Hangzhou 310003, China.
Wu
Huiling
H
Feng
Jianying
J
Shibata
Takanori
T
Hu
Ji'an
J
Zhang
Yinkai
Y
Xie
Zhijian
Z
D000222:Adaptation, Physiological; D000818:Animals; D001522:Behavior, Animal; D004547:Elastic Tissue / Q000473:pathology*; D005109:Extracellular Matrix / Q000473:pathology*; D004204:Joint Dislocations / Q000473:pathology*; D011817:Rabbits; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000473:pathology*