Ultrastructural characteristics of the gerbil pterygoid medial muscle after experimental occlusal alteration.
Ten male young adult gerbils Meriones unguiculatus weighing 55g were divided in two groups: experimental (n=5) animals submitted to exodontia of the left upper molars, and sham-operated were used as control (n=5) group. The aim of the present study was to investigate the ultrastructural effects of occlusal alteration induced by unilateral exodontia on medial pterygoid muscle. After 60 days, the animals were sacrificed by perfusion intracardially with a modified Karnovsky solution after anesthetized with overdose of urethane (3g/kg i.p.). The small samples of this muscle were fixed in 2.5% glutaraldehyde solution and post-fixed in 1% buffered osmium tetroxide solution, dehydrated in ascending concentration of ethanol, and embedded in Spurr resin. Several micrographs data showed that in this period of time, the unilateral teeth extraction was able to induce modifications on the medial pterygoid muscle fibers and capillaries at ultrastructural levels as compared to control muscles and to the ones in the contralateral side of the experimental animals. Ultrastructural changes suggest that injury was greater in the hypofunctional muscle, ipsilateral to teeth extraction.
Iyomasa
Mamie Mizusaki
MM
Faculty of Dentistry of Ribeirão Preto, University of São Paulo, São Paulo, Brazil. mamieiyo@forp.usp.br
Issa
João Paulo Mardegan
JP
Sosthines
Márcia Consentino Kronka
MC
Oliveira
Ana Maria De
AM
Stuani
Maria Bernadete Sasso
MB
Motoyama
Aracy Akiko
AA
Watanabe
Ii-Sei
IS
D000818:Animals; D005849:Gerbillinae; D008297:Male; D046529:Microscopy, Electron, Transmission; D008963:Molar; D011626:Pterygoid Muscles / Q000648:ultrastructure*; D014081:Tooth Extraction