• 대한치과교정학회지
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• 제22권2호
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• pp.345-372
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• 1992

The purpose of this experiment was to study the effects of changes of mandibular position on temporomandibular joint in internal derangement patients Twenty-four female New Zealand White Rabbits, weighing over 3.5kg, were utilized in this study . Bilateral temporomandibular joint surgery was performed in twenty-one of the rabbits to displace disc anteriorly through incising the retrodiscal tissue 1-2mm posterior to the disc, thus inducing internal derangement. They were divided into three groups nine were left untreated after surgery, six were fitted with functional protrusive appliances 4 weeks after surgery, and six wore collar appliances to apply 4 ounces of mandibular refractive force per side 4 weeks after surgery. The remaining three served as the control group. Histologic examinations were performed after sacrificing them by threes at 4-week intervals. The results were as follows. 1. Histologic findings similar to internal derangement were observed in the rabbits whose retrodiscal tissues had been incised. 2. In the rabbits untreated after surgery, articular surface on condylar process and articular eminence showed severe erosion and deformation, and displaced disc manifested changes in both shape and internal architecture. 3. Functional protrusion after surgery resulted in progressive remodeling on postero-superior portion of condyle and glenoid fossa, while it also brought about erosion on articular eminence and anterior portion of condyle. 4. Mandibular retraction after surgery resulted in compression of retrodiscal tissue and regressive remodeling of posterior portion of condyle.

• 대한치과교정학회지
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• 제23권4호
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• pp.503-527
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• 1993

This paper describes a new method to create an animal model for TMJ internal derangement in the New Zealand white rabbits and the light and electron microscopical changes of posterior attachment of them. Twenty six rabbits(2.5-3.0kg), four normal and twenty two experimental, were used. The right disc of experimental animal was displaced anteriorly without sectioning the posterior attachment and tied to the zygomatic arch with nylon not to be reduced to the original position. The left TMJ was sham-operated to be compared with its right experimental one. Normal animals were sacrificed one day and eight weeks after experiment. Experimental animals were sacrificed one day, ten days, three weeks, five weeks and eight weeks after surgery respectively. They were fixed intravenously with $2\%$ glutaldehyde under general anesthesia and the samples of them were processed for light and electron microscopic examination. The purpose of this experiment is to make a suitable animal model of disc displacement without reduction for studying and understanding the cellular and morphologic events in posterior attachment of TMJ including early changes which were difficult to be observed in human TMJs. The results of this investigation suggest the following conclusions : 1. Authors induced anterior disc displacement surgically in rabbits with new method to examine histologic changes of posterior attachment. Tissue reactions of this model seem to be similar to those observed in human disc displacement. We think this animal model for anterior disc displacement may be used to explore and evaluate objectively the effects of many treatment modalities in disc displacements. 2. The animal disease model showed inflammation at early stage(one and ten days). At this stage there were mild-to-severe mononuclear inflammatory cell infiltration, numerous newly formed vessels, vessel dilatation and engormement and many fibroblasts. 3. At middle stage(three weeks), fibrosis occurred, where fibroblasts decreased in number, but their cytoplasm was profuse indicating high activity. Collagen fibers increased in number and the tissue looked more dense. 4. At late stage(five weeks and eight weeks) showed degenerative changes including perforation of posterior attachment, disintegration of collagen fiber bundles, degeneration of fibroblasts, metastatic ossification, and dystrophic calcification.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권1호
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• pp.9-15
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• 2005

The objective of this study is screening the shear stress related proteins in chondrocytes using twodimensional electrophresis and MALDI-TOF. C-28/I2 cell line were grown. The fluid-induced shear stress(FISS) was applied using a cone viscometer at a rotational velocity of 80rpm for periods of 12 hours. Control cultures were tested under identical conditions without mechanical load application. Collected samples were used for the two-dimensional electrophoresis and MALDI-TOF. The identified proteins were calcyclin, RPE-spondin, interleukin-2, extracellular signal regulated kinase (ERK), lamin B2, porA protein, and RET-ELE1 protein. All of them showed a decreased expression. In conclusion, seven proteins were identified as a shear stress related proteins in chondrocytes. As the destruction of articular cartilage is one of main pathogenesis of TMJ internal derangement, this study will give useful information for the understanding of the molecular aspect of TMJ disease.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.36-41
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• 2006

Objective. The objective of this study was to examine the hypothesis that inflammatory synovial fluid from TMJ internal derangement initiates a transient increase in intracellular calcium concentration ([$Ca^{2+}$]i) in chondrocytes and the induced Ca2+ signaling affects iNOS/COX-2 gene expression patterns following exposure to inflamed synovial fluid. Materials and Methods. Two female adult patients with symptoms of TMD who agreed to participate in the study were selected for this study. Immortalized human juvenile costal chondrocyte C-28/I2 was grown to 80% confluency and synovial fluids from two patients were added respectively to culture media for 24 hours at the concentration of 100ng/10ml. Confocal laser scanning microscope (CLSM) was used to examine changes of intracellular calcium concentration ([$Ca^{2+}$]i). RT-PCR was performed to identify the expression profile of IL-1${\alpha}$, iNOS, COX-2. Results. Increased [$Ca^{2+}$]i was observed in chondrocytes subjected to inflamed synovial fluid compared to control cultures and in respective cultures exposed to inflamed synovial fluids from each patient, IL-1${\beta}$, COX-2 mRNA were detected. However, in neither case iNOS mRNA was expressed. IL-1${\alpha}$, COX-2, and iNOS mRNA were expressed in control culture. Conclusion. Our results show that immortalized chondrocytes cultured with inflamed synovial fluids from patients diagnosed as disc displacement without reduction and limitation in mouth opening showed increased calcium concentration and expression of COX-2 while inhibiting the production of iNOS, which in turn could adversely affect the chondrocytes in at least short term by hindering physiologic role of NO against inflammatory cascades. These findings suggest that inflamed synovial fluid may differentially regulate the transcriptomes of relevant inflammatory mediators, especially iNOS/COX-2 axis in chondrocytes through adjusting calcium transients.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권3호
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• pp.447-457
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• 1994

Authors have studied retrospectively the facial nerve injury after TMJ surgery through the preauricular approach routine. The study material used was 4 patients of all 113 patients who were diagnosed as internal derangement and have been operated from March 1989 to February 1991 in Youngdong severance hospital, and were induced postoperatived facial nerve injury. The patient group who had the postoperative injured facial nerve was recognized degree of injury using the diagnostic method, Electromyography(EMG) and Nerve conduction test(NCT) which are used widely at present and was treated as conservative care and we identified the recovery time as the same method. The results as follows : 1. The meticulous care and precious surgical technique are needed in both operation and postoperation. During the TMJ surgery, the excessive retraction of the flap and frequent use of nerve stimulator and electric surgical knife should be avoided as possible and postoperative hematoma and swelling should be minimized. 2. The 4 patients were experienced with the postoperative facial nerve injury of all 133 patients who had been operated the TMJ surgery through the routine preauricular approach on our hospital. And the incidence of postoperative facial nerve injury happened was about 0.3% and its incidence was relatively low comparing with any other previous reports. 3. EMG and NCT were considered as useful methods which can diagnose the nerve injury objectively and identified the effect of treatment and recovery time. 4. The faical nerve-injured patients who were induced postoperatively after TMJ surgery, were diagnosed as second-degree nere injury through the EMG and NCT. And the patient group was treated well as conservative physical therapy for about 2 to 4 months.

• Journal of Yeungnam Medical Science
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• 제25권1호
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• pp.41-49
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• 2008

한탄바이러스가 혈소판활성인자 활성에 영향을 미치는지 알아보기 위하여 간접적으로 혈소판활성인자 수용체의 발현과 분해효소의 활성을 측정하였다. 혈관내피세포에서 혈소판활성인자 수용체의 유전자를 역전사 중합효소연쇄반응으로, 단백질은 western blot으로 측정하였다. 또한 세포표면에 발현된 혈소판활성인자 수용체의 양은 FACS로 분석하였다. 한탄바이러스에 감염된 혈관내피세포에서 혈소판활성인자 수용체의 유전자, 단백질, 세포 표면의 발현 모두 바이러스에 감염되지 않은 대조 세포보다 감염 후 2, 3일째 증가 하였다. 혈액 내 혈소판활성인자 분해효소의 활성을 비교한 결과 신증후출혈열 환자에서 정상인에 비하여 2.5배 낮았다. 그리고 신증후출혈열 환자가 회복됨에 따라 혈소판활성인자의 활성이 다시 정상 수준으로 회복되는 것으로 나타났다. 따라서 한탄바이러스에 의해 증가된 혈소판활성인자 수용체의 발현이 혈소판활성인자와 혈관내피세포와 반응성을 증가시키고, 신증후출혈열 환자 혈액에서 감소된 혈소판활성인자 분해효소가 혈소판활성인자의 분해를 지연 시켜 작용시간을 증가 시킴으로써 과다한 혈소판활성인자의 생물학적 작용이 신증후출혈열의 병리현상을 초래할 것으로 사료된다.