• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.63-68
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• 1991

The author has arrived at the following result after having carried out multilateral study based on a total of 282 maxillofacial fracture patients who have receive treatment at the Euijeongbu general hospital and Shinchun general hospital in the northern district of Kyunggido from march 1988 to august 1990. 1. Sex distribution of Mx. facial fx. patient was higher in male by 4.6:1 and was predominant in the 3rd decade with 40.4% followed in decreasing order by the 2nd decade and the 4th. 2. A majority were in the Mn. with 40.2% followed in decreasing order by zygoma. nasal bone and maxilla. 3. For the sex distribution according to anatomy, make to female ratio was 6.2:1 in the mandible, followed in decreasing order by zygoma, and nasal bone with predominance in male. 4. Car accident with 42.8% was the most common cause of fx. followed in decreasing order by violence, workmen's accident, and fall down. 5. The involvement of other trauma areas are head. 79.0%, abdomen-thorax, and the extremities in decreasing order. 6. In the mandibular fx. a majority were in the symphysis with 73.9% followed in decreasing order by angle, Condyle, and body. 7. Maxillary fx. of the type LeFort II was estimated to be 41.2% 8. Fracture in the zygoma including zygomatic arch was estimated to be 72.5%

• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.237-243
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• 2006

The aims of this study was to investigate the clinical and radiographic features of temporomandibular dysfunction in the patients with RA to elucidate whether the RA patients would be a risk group for TMD. The 35 patients with temporomandibular joint dysfunction were included for this study, of which 15 had rheumatoid arthritis diagnosed by a rheumatologist, and other 20 was control group and they didn't have any history or clinical signs related to it. Clinical symptoms and signs of temporomandibular joint disorders, radiographic and MRI findings of temporomandibular joint were investigated. The results were compared between two groups. In RA group bilateral pain, morning stiffness, reduced opening range, and crepitations were more frequently reported than control group. Radiologic findings such as sclerosis and flattening of condylar head, marginal proliferation, and erosion of glenoid fossa were more frequently observed in RA group than control group. Disk destruction, cortical bone erosion, and intraarticular enhancement were more prominenet in RA group. From theses results, it can be concluded that many RA patients will develop TMD symptoms and the structural changes of TMJ is more extensive than the usual TMD cases.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.1
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• pp.56-59
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• 2003

The incident of false aneurysm of internal maxillary artery in the oral and maxillofacial region is known to be very rare. One case of false aneurysm in the internal maxillary artery is presented, which was experienced in our department. The etiology of this case is regarded as the mandibular condyle fracture, and/or iatrogenic trauma during open reduction. Clinically, there were systolic bruit on auscultation, pulsation and massive bleeding during operation. The lesion was finally diagnosed with angiography and treated by embolization procedure. False aneurysm can cause so massive bleeding as to threat the life of the patients. Therefore accurate diagnosis and treatment is very important. Angiography enables the solid diagnosis for the clinical one. And as the embolization has many advantages over the ligation, it can be a good treatment method.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.3
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• pp.517-534
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• 1997

It has been held that excessive mechanical forces to the osseous and soft tissues of the TMJ result in joint dysfunction. Understanding the stress pattern on TMJ is very important in TMJ research. But, it is very difficult to measure directly the biomechanical stress distribution in the TMJ when the mandible is loaded. Therefore, stress distribution in the TMJ during functional movement was studied through animal experiment or mathematical model. It was observed and compared the stress distribution occuring in the working and balancing condyle when lower right canine, lower right first molar and lower right second molar were clenched by the three dimensional finite element analysis. Also, stress distribution in the working and balancing condyles were observed and compared when $20^{\circ}$ forward and buccal bite forces were applied to the first molar. The results were as follows : 1. Stress distribution in the condyles during unilateral clenching of the first molar, second molar, canine showed no difference. In the working condyle, tensile force was concentrated on the lateral aspect of the condylar articular surface and condylar neck. And compressive force was concentrated on the anteromedial and lateral aspect of condyle. In the balancing condyle, tensile and compressive forces were concentrated on the lateral aspect of the condylar articular surface and stress transmission to the temporal bone was not observed. 2. When lateral forces were applied to the first molar, tensile forces were concentrated on the medial aspect of the condylar neck and condylar posterior surface in working and balancing condyle. Compressive force was concentrated on the anteromedial and lateral surface of the condyle and stress transmission to the temporal bone was not observed. 3. During unilateral clenching, stress in the working condyle decreased as the occlusal load moved posteriorly while the stress in the balancing condyle increased. when lateral force was applied to first molar, the incremental amount of stress was greater than vertical load. 4. During unilateral clenching, the average balancing/working condyle stress ratio was 2.52. There was a greater concentration of stress in the balancing condyle. The ratio increased as the occlusal load moved posteriorly and decreased considerably when lateral forces were applied to the first molar.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.33-43
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• 2023

Pathological wear across the entire dentition causes problems such as collapsed occlusal plane, reduced vertical dimension, anterior premature contact, inadequate anterior guidance, and tooth migration, thereby induce symptoms such as temporomandibular joint disorder, reduced masticatory efficiency, and tooth hypersensitivity. For the treatment of patients with excessive wear, evaluation of vertical dimension should be preceded along with analysis of the cause. The patient in this case was a 45-year-old female with a history of orthognathic surgery. Through clinical examination, radiographic examination, and model analysis, overall tooth wear, interdental spacing in the anterior maxillary region, retruded condylar position, and insufficient interocclusal space for prosthetic restoration were confirmed. Full mouth rehabilitation with increased vertical dimension was planned, the patient's adaptation to the new vertical dimension was evaluated with a removable occlusal splint and temporary prosthesis, and cross-mounting was performed based on the temporary restoration to fabricate the definitive zirconia prosthesis, maintaining the adjusted vertical dimension. It showed satisfactory functional and esthetic results through stable restoration of the occlusal relationship.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.1
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• pp.64-71
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• 2024

The most critical aspect of full-arch prosthodontic treatment is evaluating whether the patient's vertical occlusal dimension is appropriate, and if necessary, restoring it through increasing vertical dimension. If the vertical occlusal dimension is too low, it can lead to reduced chewing efficiency, as well as not only aesthetic concerns but also potential issues like hyperactivity of muscles and posterior displacement of the mandible. This report is about the patient dissatisfied with pronunciation and aesthetics due to an inappropriate vertical occlusal dimension resulting from prior prosthetic interventions, underwent full-arch prosthodontic restoration treatment. Through the utilization of digital diagnostic apparatus, a comprehensive evaluation was undertaken for patient's vertical occlusal dimension, occlusal plane orientation, and the condition of prosthetic restorations. Through 3D facial scanning, the facial landmarks were discerned, and subsequently, the new occlusal plane was established. This provided the foundation for a digitally guided diagnostic wax-up. An elevation of 5 mm from the incisor was determined. Comprehensive dental rehabilitation was then executed for all remaining teeth, excluding the maxillary four incisors. The treatment protocol followed a systematic approach by initially creating implant-supported restorations on both sides of the dental arch to establish a stable occlusal contact. Subsequently, prosthetic restorations for the natural dentition were generated. Diagnostic and treatment planning were established through the utilization of facial scanning. This subsequently led to a reduction in treatment complexity and an expedited treatment timeline.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.33-41
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• 2000

Although it is well known that the chincup, used to correct a skeletal class III malocclusion in growing children, reduce the mandibular prognathism by arresting the growth of the mandibular length and rotating the mandible posteroinferiorly, the majority of the studies about chincup is focused on condylar head that plays an Important role in mandibular growth. The aim of this study was to evaluate the morphologic change of the mandibular symphysis where extraoral force is applied directly during chincup treatment. The data lot this study were obtained from lateral cephalometric radiographs of 62 growing children(chincup group:32, control group:30) with mixed dentition who had been accepted lot the orthodontic treatment at Chonbuk National University Dental Hospital. The results were as follows : 1. Symphysis height was increased both in chincup therapy group and control group during treatment. Symphysis depth was decreased or maintained the initial values in chin cup therapy group, whereas increased in control group. Posterior symphysis depth was decreased both in chin cup therapy group and control group, but anterior svmphysis detph was increased in control group, whereas decreased in chincup therapy group. 2. Chin depth and chin curvature were increased in control group, whereas maintained or decreased in chincup therapy group during treatment. Chin angle, menton ang1e and symphysis angle were decreased in control group, whereas increased in chincup therapy group. It suggested that bone deposition in pogonion area that occur normally with mandibular growth was supressed by direct contact of chincup. 3. When growing children wear chincup, symphysis morphology was maintained due to inhibition of forward growth at mandibular symphysis. It may be due to the suppression of bone deposition in anterior part of symphysis.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.499-506
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• 1999

The odontoma is relatively a common benign odontogenic tumor and caused by overgrowth of odontogenic tissues. The recent classification by World Health Organization divides odontoma into 2 groups such as compound odontoma and complex odontoma. Compound odontoma comprises dental tissues, resembling the morphology of a tooth and has predilection for the anterior maxilla. In contrast, complex odontoma has unorganized mass, not resembling the normal tooth and has predilection for the posterior mandible. The etiology of odontoma is unknown and almost asymptomatic. So, it usually is found in routine radiographic examination, and most common presenting symptom is impacted or unerupted permanent teeth and retained primary teeth. It can occurs almost anywhere in jaws. It is desirable that odontoma should be removed by surgical enucleation including follicle and surrounding soft tissues. Considering the age and behavioral cooperation of patient, the development of permanent dentition, the location of odontoma in jaw, the need for the concomitant operative dentistry, operation is performed in outpatient department with/without sedation or under general anesthesia with endotracheal intubation. In this case report, 2 patients with compound odontoma were treated by surgical enucleation including follicle and surrounding soft tissues. One patient, about 5 years old, was treated under general anesthesia and concomitant operative dentistry was performed. The other patient, about 11 years old, was treated under local anesthesia in outpatient department. In 2 cases, after 4 months, surgical defects were filled with new bone and normalization of eruption path of impacted permanent teeth was observed.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.283-305
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• 2001

The purpose of this study was to analyze the stress distribution of condylar regions and edentulous mandible with implant-supported cantilever prostheses on the certain conditions, such as amount of load, location of load, direction of load, fixation or non-fixation on the condylar regions. Three dimensional finite element analysis was used for this study. FEM model was created by using commercial software, ANSYS(Swanson, Inc., U.S.A.). Fixed model which was fixed on the condylar regions was modeled with 74323 elements and 15387 nodes and spring model which was sprung on the condylar regions was modeled with 75020 elements and 15887 nodes. Six Br${\aa}$nemark implants with 3.75 mm diameter and 13 mm length were incorporated in the models. The placement was 4.4 mm from the midline for the first implant; the other two in each quardrant were 6.5 mm apart. The stress distribution on each model through the designed mandible was evaluated under 500N vertical load, 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. The load points were at 0 mm, 10 mm, 20 mm along the cantilever prostheses from the center of the distal fixture. The results were as follows; 1. The stress distribution of condylar regions between two models showed conspicuous differences. Fixed model showed conspicuous stress concentration on the condylar regions than spring model under vertical load only. On the other hand, spring model showed conspicuous stress concentration on the condylar regions than fixed model under 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. 2. Fixed model showed stress concentration on the posterior and mesial side of working and balancing condylar necks but spring model showed stress concentration on the posterior and mesial side of working condylar neck and the posterior and lateral side of balancing condylar neck under vertical load. 3. Fixed model showed stress concentration on the posterior and lateral side of working condylar neck and the anterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior sides of working and balancing condylar necks under horizontal load linguobuccally. 4. Fixed model showed stress concentration on the posterior side of working condylar neck and the posterior and lateral side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 20 degree oblique load. 5. Fixed model showed stress concentration on the anterior and lateral side of working condylar neck and the posterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 45 degree oblique load.. 6. The stress distribution of bone around implants between two models revealed difference slightly. In general, magnitude of Von Mises stress was the greatest at the bone around the most distal implant and the progressive decrease more and more mesially. Under vertical load, the stress values were similar between implant neck and superstructure vertically, besides the greatest on the distal side horizontally. 7. Under horizontal load linguobuccally, buccal 20 degree oblique load and buccal 45 degree oblique load, the stress values were the greatest on the implant neck vertically, and great on the labial and lingual sides horizontally. After all, it was considered that spring model was an indispensable condition for the comprehension of the stress distributions of condylar regions.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.235-243
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• 2000

Magnetic resonance imaging(MRI) of the temporomandibular joint(TMJ) is very useful method to diagnose internal derangement of the TMJ because of its high specificity foy identification of condyle-disc relationships. The purpose of this study was to evaluate the existence, incidence and severity o』 internal derangement o』 the TMJ by the MRI of Patients who are suspected to have TMJ disorder. MRI sample was composed of 50 subjects(10 males, 40 females) and the mean age was 22.9 years. 43 subjects of the sample were found to have positive findings. $56\%$ of the subjects with positive findings had ADD(anterior disc displacement) without reduction, and $65\%$ had internal derangement of bilateral joints. Distributions in the types of malocclusion in patients with positive findings, the Angle's classification had shown : the largest $41.9\%$ for Cl II ($39.6\%$ for Cl II div 1 and $2.3\%$ for Cl II div 2), $37.2\%$ for Cl I, $18.6\%$ for Cl III, and $2.3\%$ for the unidentified. $8.6\%$ of the subjects with positive findings had facial asymmetry and $55.8\%$ had openbite. We can conclude that the percentage of Cl II is the highest in patients with internal derangement of the TMJ. Openbite or facial asymmetry is considered to be uncompensated or compensated deformity which results from facial skeleton remodeling in the process of degenerative joint disease(DJD) due to TMJ degeneration. Therefore it is recommended to screen the patients with facial asymmetry or openbite by MRI before the beginning of orthodontic treatment. Differential diagnosis is essential because the tendency of relapse is high after the orthodontic treatment and continuous observation of TMJ is needed in patients with TMJ disorder.