Qualitative study of young, adult, and aged Wistar rats temporomandibular synovial membrane employing light, scanning, and transmission electron microscopy.
The aim of this study was to analyze the rat temporomandibular joint (TMJ) synovial membrane at different ages using light, scanning, and transmission electron microscopy. Under light microscopic analysis, the TMJ structures were observed such as condyle, capsule, disk, the synovial membrane collagen type, and cells distribution. In the scanning electron microscopy, the synovial membrane surface exhibited a smooth aspect in young animals and there was an increase with ageing in the number of folds. The transmission electron microscopic analysis showed more synoviocytes in the synovial layer in the young group and still a great number of vesicles and cisterns dilation of rough endoplasmic reticulum in the aged group. In the three groups, a dense layer of collagen fibers in the synovial layer and cytoplasmic extensions were clearly seen. It was possible to conclude that synovial membrane structures in aged group showed alterations contributing to the decrease in joint lubrication and in the sliding between disk and joint surfaces. These characteristic will reflect in biomechanics of chewing, and may cause the TMJ disorders, currently observed in clinical processes.
Department of Morphology and Genetics, Federal University of São Paulo, São Paulo, Brazil.
Christiano Cony
CC
Duro
Adriano Polican
AP
Ciena
Sonia Regina Yokomizo
SR
De Almeida
Marta Maria Da Silva
MM
Righetti
Débora De Freitas
Dde F
Grisolia
João Paulo Mardegan
JP
Issa
Marcelo Cavenaghi Pereira
MC
Da Silva
Ii-Sei
IS
Watanabe
D000375:Aging; D000818:Animals; D008853:Microscopy; D017208:Rats, Wistar; D013583:Synovial Membrane / Q000033:anatomy & histology* / Q000648:ultrastructure*; D013704:Temporomandibular Joint / Q000033:anatomy & histology* / Q000648:ultrastructure*