The present study was designed to consider the changes of the temporomandibular joint after mandibular oblique osteotomy of the cats.
In order to carry out this experiment, 17 cats weighing about 3.0kg were selected. One cat was preserved for control and 16 animals were divided into 8 groups, 1 day, 3 days, 5 days, 1 week, 2 weeks, 4 weeks, 6 weeks and 8 weeks.
Under the general anesthesia with pentobarbital sodium, the experimental animals were performed oblique osteotomy on both mandibular ramus and wire fixation at mandibular border.
The experimental animals were sacrificed consecutively on the 1st day, 3rd day, the 5th day, the 1st week, the 2nd week, the 4th week, the 6th week, the 8th week after surgery and the mandible were dissected out carefully to produce tissue
specimen.
The specimens were fixed with 10% formalin solution for 24 hours and rinsed with phosphate buffer solution. It was decalcified with 5% nitric acid for 15 days. Thereafter the specimens were dehydrated in alcohol series and embedded paraffin as
usual
manner. The embedded specimen were sectioned in 4-6μm, stained with hematoxylin-eosin and immunohistochemical stain, and observed through light microscope and polarizing microscope.
@ES The results were as follows:
@EN 1. The remarkable changes were appeard in the articular surfaces of temporal bone, the articular disc, the retrodiscal tissue, the fibrocartilage layer of condyle, the hypertrophic layer of condyle, the bone marrow of condyle at the 1st week
after
treatment.
Extreme hyperplasia of the fibrocartilage layer and thickening of prechondroblastic-chondroblastic layer in the 2 weeks after treatment.
In the 6th and 8th week post experimental animals, a pattern of response observed dense, regular arrangement in the fibrocartilage layer of the articular fossa and the mandibular condyle and in the articular disc.
The TGF gradually appeared in condylar bone marrow at 5 days after and increased at 2 weeks after and decreased at 8 weeks after.
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