• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.3
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• pp.211-224
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• 2009

The objective of this study is to examine the condylar surfaces in order to find out the types, the incidence and common occurrence area of the osseous abnormalities of the condyles according to the age, genders and the purpose of CT taking, and to compare those between the groups for TMD diagnosis and the other groups. 3D CT images of 199 patients which were scanned with the $i-CAT^{TM}$ Cone Beam Computed Tomography were collected from Sanbon Dental Hospital of Wonkwang university and the MPR images were transfered to the TMJ mode to be showed serial sagittal images and coronal images. The images were macroscopically examined by three independent observers for the types and incidences of the osseous abnormalities, their common occurrence area and general shapes of the condyles. As a result, type F is most common ever than type N. The common occurrence area in sagittal images is antero-superior and superior area except for type D-C which were showed on postero-superior area commonly. In coronal images, latero-superior and superior area is most common except for type E which were present on mesio-superior and superior area most frequently. The osseous abnormalities of the condyles are more common in TMD diagnosis group except for type D-C, that is type N and type D-C are more common in the other groups. In this study, abnormalities of the condyles are classified into 6 types and it has a common occurrence area each. And TMD diagnosis group shows a tendency to have higher rate for osseous abnormalities except for type D-C.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.1
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• pp.87-103
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• 1999

Purpose: This study was undertaken to quantitatively estimate the degree of the damage and recovery of the irradiated rat condylar cartilage using the Image Analyzer. Materials and Methods: Experimental animals were 16 male rats of the Sprague-Dawley strain at the age of 20 day irradiated with the dose of 10 Gy in their head and neck region. Four rats were sacrificed at the each of the following time intervals - 1, 4, 7 and 14 days, respectively. The same number of control group animals were sacrificed at the each age of 21. 24, 27 and 34 days, respectively. The specimens were stained with 0.5％ toluidine blue and examined with light microscope. The condylar cartilage was divided into 4 zones; fibrous zone, proliferating zone, upper hypertrophic zone, and lower hypertrophic zone. And then, the proliferating zone was subdivided into 2 layers - upper and lower layer, and upper and lower hypertrophic zone were subdivided into three layers, respectively - upper, middle and lower layer. With the aid of Image Analyzer, morphometric analysis was performed. The thickness, the numerical density of cells, the cell area density, the extracellular matrix area density, the mean area of single cell, the mean area of extracellular matrix per single cell were measured and analysed. Results: In the experimental group, the thickness of the fibrous zone was slightly increased and that of the proliferating zone and the upper and the lower hypertrophic zone was markedly decreased. With time, the thickness of the fibrous zone was gradually increased and that of the proliferating zone and the upper and the lower hypertrophic zone was steadily in the decreased state. The numerical density of cells of the proliferating zone was increased on post-irradiated 1 day, but decreased after post-irradiated 4 day, and that of the upper hypertrophic zone was decreased. The numerical density of cells of the lower hypertrophic zone was decreased in the early stage and then was decreased or not significantly different from that of the control group with time. In the experimental group, the cell area density of the fibrous zone and the proliferating zone was decreased in the early stage and then gradually increased or not significantly different from that of the control group with time. The cell area density of the upper and the lower hypertrophic zone was varied with time. The extracellular matrix area density value were totally opposite to the cell area density values: The mean area of single cell of the fibrous zone and the proliferating zone was .decreased on post-irradiated 1 day, and increased after post-irradiated 4 day. The mean area of single cell of the upper hypertrophic zone was varied with each layer and time. In the experimental group, the mean area of extracellular matrix per single cell of the fibrous zone was not significantly different with control group, and that of the proliferating zone was decreased on post-irradiated 1 day, and increased after post-irradiated 4 day. The mean area of extracellular matrix per single cell of the lower hypertrophic zone was increased in the early stage. and that of upper hypertrophic zone was varied with each layer and time. Conclusion: The condylar cartilages of rats were affected by irradiation, but the changes were vaned with each layer and time. By morphometric analysis. the changes of the cells of the condylar cartilage of irradiated rat could be calculated quantitatively.