• Imaging Science in Dentistry
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• 제33권2호
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• pp.85-90
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• 2003

Purpose : To investigate the differences between the position of the mandibular condyles in temporomandibular joints of patients presenting with normal occlusion and skeletal class III malocclusion. Materials and Methods: Forty-two subjects with normal occlusion and thirty-seven subjects exhibiting skeletal class III malocclusion prior to orthodontic treatment were included in the study. Transcranial radiographs of each subject were taken at centric occlusion and 1 inch mouth opening. The positional relationship between the mandibular condyles with articular fossae and articular eminences at two positional states were evaluated and analyzed statistically. Results: The mandibular condyles of the skeletal class III malocclusion group were found to be located more anteriorly from the center of the articular fossae compared to the normal occlusion group in centric occlusion. The mandibular condyles of the skeletal Class III malocclusion group were located more superiorly from the middle of articular height than those of the normal occlusion group in centric occlusion. However, these differences were not statistically significant. At 1 inch mouth opening, the mandibular condyles of the skeletal class III malocclusion group were placed more posteriorly from the articular eminences than those of the normal occlusion group. The mean angle of the articular eminence posterior slope were 56.51 ° ± 6.29° in the normal occlusion group and 60.37° ± 6.26° in the skeletal Class III malocclusion group. Conclusions: The mandibular condyles of the skeletal Class III malocclusion group were placed more anteriorly at centric occlusion and more posteriorly at 1 inch mouth opening when compared with those of the normal occlusion group.

• 대한치과의사협회지
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• 제58권6호
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• pp.364-376
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• 2020

Internal derangement of the temporomandibular joint (TMJ) is condition in which articular disc has become displaced from its normal functional relationship with the mandibular condyle and the articular portion of the temporal bone. Common types of internal derangement include disc displacement with reduction (with or without intermittent locking), and disc displacement without reduction (with or without limited opening) classified according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Treatment varies depending on diagnosis. Therefore, differential diagnosis should be made for appropriate treatment.

• 대한치과의사협회지
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• 제24권5호통권204호
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• pp.439-447
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• 1986

The occurrence of osteochondroma, osteoma in mandibular condlye is rare. Sign and symptoms of enlargement of condyle are open bite, cross bite, myofascial symptoms, facial asymmetry. They are treated via condylectomy, subcondylar ostetomy, etc. We treated osteochondroma with condylectomy, osteoma with condylectomy & arthroplasty with titanium mesh & resin ball. Followings are the results 1. Condylectomy of osteochondroma resulted in good function & esthetics except slight deviation of mandible to the operation side during mouth opening. 2. Condylectomy & arthroplasty with titanium mesh & resin ball resulted in good function & esthetics & no deviation of mandible.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권5호
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• pp.356-360
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• 2017

The tympanic plate is a small part of the temporal bone that separates the mandibular condyle from the external auditory canal. Fracture of this small plate is rare and usually associated with other bony fractures, mainly temporal and mandibular bone. There is a limited amount of literature on this subject, which increases the chance of cases being overlooked by physicians and radiologists. This is further supported by purely isolated cases of tympanic plate fracture without evidence of other bony fractures. Cone-beam computed tomography is an investigative three-dimensional imaging modality that can be used to detect fine structures and fractures in maxillofacial trauma. This article presents four cases of isolated tympanic plate fracture diagnosed by cone-beam computed tomography with no evidence of fracture involving other bones and review of the literature.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권3호
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• pp.204-210
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• 2007

This study was intended to compare the cranial base morphology between the mandibular prognathism and maxillary retrognathism in skeletal class III patients. The subject of the present study was composed of 88 patients divided into two groups; Group 1 (Skeletal Class III with mandibular prognathism. SNA within normal range, SNB over normal range, n=54) and Group 2(Skeletal Class III with maxillary retrognathism. SNA below normal range, SNB within normal range, n=34). Lateral cephalogram were taken immediate before surgery and 18 landmarks were used to analyze the characteristics of cranial base and maxillomandibular skeleton. The result revealed that cranial base angle is significantly smaller in Group 1 than Group 2, which implies the influence of the cranial base angulation on the mandibular position. However the posterior cranial base length did not influence the mandibular horizontal position and anterior cranial base length did not influence the maxillary horizontal position. As the anterior cranial base length was closely related with ramal height, it is recommendable to investigate the regulatory mechanism of chondrogenesis of cranial base and condyle cartilage in the future research.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권1호
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• pp.35-42
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• 2003

Purpose: This study was aimed to investigate the relationship between the mandibular asymmetry and the internal derangement of temporomandibular joint. Materials and methods: One hundred and sixty eight patients had been assessed through clinical examinations, panoramic radiographs and magnetic resonance imagings (MRIs), were selected. The samples were classified into three subgroups according to the severity of the mandibular asymmetries in the panoramic radiographs and the status of TMJ discs on the MRI were compared among each groups. Results: In an apparent asymmetry group, there was a significant difference in the number of temporomandibular disk displacement without reduction between the long and short side (66.7%, 18/27 joints on the short side) when the ratio of condylar process and coronoid process was used (p<0.05), but there was no statistically significant difference when the ratio of condyle and ramus was used. Conclusion: The probability of the disc displacement without reduction was higher at the side with relatively shorter condylar process on the panoramic radiograph, and also it might be more effective to use ratio of condylar process and coronoid process in the assessment of mandibular asymmetry. Therefore, a careful assessment on the temporomandibular disorders is necessary to diagnose and establish the treatment plans for the patients with a mandibular asymmetry and the panoramic radiograph can be used effectively on that way.

• 대한치과교정학회지
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• 제19권1호
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• pp.153-167
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• 1989

This study was undertaken to analyze the growth of mandible in surgically repaired unilateral cleft lip and palate. The subjects consisted of 63 unilateral cleft lip and palate individuals, 60 class III malocclusions and 60 normal occlusions ranging from 6 to 15 years old. Each group was divided into two age groups. (6-10 Y and 11-15 Y) The results obtained from UCLP compared with other groups were as follows: 1. The anteroposterior position of the chin was similar to that of the normal occlusions. 2. The shape of the mandible was similar to that of the class III malocclusions. 3. In mandibular size, ramus height was the smallest among three groups, but body length and overall mandibular length were similar to those of the normal occlusions. 4. The lower border of the mandible was the steepest among three groups and strong vertical or clockwise growth tendency was indicated. 5. The position of condyle in relation to the cranial base showed little difference in three groups. 6. In older age group , vertical growth tendency of the mandible decreased more or less.

• 대한치과교정학회지
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• 제16권1호
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• pp.119-131
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• 1986

The purpose of the study is to note the effects of the resection of the lateral pterygoid muscle on the mandibular growth in the growing rats. Twenty four female Wistar rats were used in the experiment. They were divided into three groups: group 1 ; bilateral sham operation group 2 ; bilateral resenction of the lateral pterygoid muscle group 3 ; unilateral resection of the lateral pterygoid muscle (The right lateral pterygoid muscle was resected and the left one was sham-operated.) Groups 1&2 were sacrificed eight weeks lateral and group 3, four weeks later. All specimens were measured with calipers, and stained with hematoxylin and eosin. Groups 1 & 2 were compared with each other. In group 3, the right side was compared with the left. The results were as follows: 1. In the growing rats, the resection of the lateral pterygoid muscle was followed by a decrease of the mandibular growth. After eight weeks, the condyle-mental foramen distance, the angular process-mental foramen distance, the size of the condylar head, the supradentale-first molar distance, and the diameter of the symphysis were significantly smaller than the control. 2. Resection of the lateral pterygoid muscle resulted in decrease of the thickness of the cartilage layer and the prechondroblastic-chondroblastic layer after four weeks. 3. After eight weeks, group 1 and group 2 were not different significantly in the histologic sections. 4. The condylar cartilage was stabilized eight weeks after the experiment.

• Archives of Plastic Surgery
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• 제39권4호
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• pp.284-290
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• 2012

Open reduction and anatomic reduction can create better function for the temporomandibular joint, compared with closed treatment in mandible fracture surgery. Therefore, the double miniplate fixation technique via mini-retromandibular incision was used in order to make the most stable fixation when performing subcondylar fracture surgery. Those approaches provide good visualization of the subcondyle from the posterior edge of the ramus, allow the surgeon to work perpendicularly to the fracture, and enable direct fracture management. Understanding the biomechanical load in the fixation of subcondylar fractures is also necessary in order to optimize fixation methods. Therefore, we measured the biomechanical loads of four different plate fixation techniques in the experimental model regarding mandibular subcondylar fractures. It was found that the loads measured in the two-plate fixation group with one dynamic compression plate (DCP) and one adaption plate showed the highest deformation and failure loads among the four fixation groups. The loads measured in the one DCP plate fixation group showed higher deformation and failure loads than the loads measured in the two adaption plate fixation group. Therefore, we conclude that the selection of the high profile plate (DCP) is also important in order to create a stable load in the subcondylar fracture.

• 치과방사선
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• 제26권2호
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• pp.7-17
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• 1996

This study was performed to determine the postitional relationships of two lobes of parenchyma and to analysis the anatomical feature and its variations of duct on the panoramic views of the normal parotid glands in adults. Materials included 66 panoramic views and anterioposterior views of sialograms of selected persons and the radiograms of the gland experimentally reproduced on dry skull with lead foil and the reference images of computed tomograms of normal persons. Results were as follows : 1. On panoramic view of sialogram, the superficial lobe was revealed with totally being superimposed with the mandibular ramus and condyle and its tail portion superimposed with mandibular angle area, the deep lobe was revealed between the posterior border of the ramus and the mastoid process, and the isthmus was begin from the marked furcation off main duct and superimposed partially with the medial part of the deep lobe. 2, The mean length and the lateral extension of parenchyma was 63.18±8.05mm and 21.78±4.87mm respectively on panoramic view and showed no statistical relationship between them. 3. The main duct was generally perpendicular to the posterior border of ramus at middle portion and its configurations revealed 57,58％ of curvilinear type, 21.21％ sigmoid type, 15.15％ reverse sigmoid type. 4, The interlobular ducts of the deep lobe showed relatively well defined features between the mandibular ramus and the mastoid process.