• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권3호
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• pp.207-217
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• 2010

The purpose of this study was to evaluate the effects of the stress distribution and displacement in mandible according to treatment modalities of mandibular angle fractures, using a three dimensional finite element analysis. A mechanical model of an edentulous mandible was generated from 3D scan. A 100-N axial load and four masticatory muscular supporting system were applied to this model. According to the number, location and materials of titanium and biodegradable polymer plates, the experimental groups were divided into five types. Type I had a single titanium plate in the superior border of mandibular angle, type II had two titanium plates in the superior tension border and in the inferior compression border of mandibular angle, type III had a single titanium plate in the ventral area of mandibular angle, type IV had a single biodegradable polymer plate in the superior border of mandibular angle, type V had a single biodegradable polymer plate in the ventral area of mandibular angle. The results obtained from this study were follows: 1. Stress was concentrated on the condylar neck of the fractured side except Type III. 2. The values of von-Mises stress of the screws were the highest in the just-posterior screw of the fracture line, and in the just-anterior screw of Type III. 3. The displacement of mandible in Type III was 0.04 mm, and in Type I, II, IV, and V were 0.10 mm. 4. The plates were the most stable in the ventral area of mandibular angle (Type III, V). In conclusion, the ventral area of mandibular angle is the most stable location in the fixation of mandibular angle fractures, and the just- posterior and/or the just-anterior screws of the fracture line must be longer than the other, and surgeons have to fix accurately these screws, and the biodegradable polymer plate also was suitable for the treatment of mandible angle fracture.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권2호
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• pp.209-214
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• 1999

Chronic recurrent TMJ dislocation results in difficulty of mastication, speaking, and swallowing due to the limitation of the mandibular movement. Etiologic factors are considered as the looseness of the capsule and ligaments, the decrease of the articular eminence, condylar morphologic change, muscular disharmony near by TMJ, and the decrease of the vertical length of the mandibular ramus. Treatment approach has been suggested that surgical methods are selected for the correction of the etiologic factors when conservative treatments are not effective. Many surgical methods have been reported such as eminectomy, eminence augmentation, condylotomy, and zygomatic arch down fracture technique. We performed the eminence augmentation through interpositional bone graft in chronic recurrent TMJ dislocation. This method leads to favorable postoperative result without recurrence and complication, so we report the case with related references.

• 대한치과교정학회지
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• 제18권1호
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• pp.189-207
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• 1988

In almost all biologic systems, mechanically induced electric charge separation is a fundamental phenomenon. Since the hypothesis was established that the generation of electric potentials in bone by mechanical stress including muscular force might control the activity in bone by mechanical stress including muscular force might control the activity of osseous cells and their biopolymeric byproduct, the concept of electrically mediate growth mechanism, which involves biological growth and bone remodeling by any means, in living systems has been applied clinically and experimentally to orthopedic fracture repair, the regulation of orthodontic tooth movement, epiphyseal cartilage regeneration, etc. On the other hand, recent numerous research data available show apparently that the mandibular condyle has the characteristics of growth center as well as growth site. In addition, there exists a considerable difference of opinion as to the role of external pterygoid muscle in condylar growth. In view of these evidences, this. experiment was performed to investigate the effect of the galavic current on the growth of the mandible and condyle for elucidating the nature of condylar growth. The bimetallic device was composed of silver and platinum electrode connected with resistor (3.9 Mohm), which was expected to produce galvanic current of 23.6 nA according to the galvanic principle. The 25 Sprague-Dawley rats were divided into two group, 2 week group comprising 8 animals exposed to satanic current for 2 weeks and 3 control animals not exposed for 2 weeks, 4 week group comprising 10 animals in experimental group and 4 animals in control group applied for 4 weeks respectively. The experimental rats were subjected to application of the galvanic current invasively to codylar head surface and the control groups with sham electrode. On the basis of anatomic and histologic data from the mandibular condyle of experimental and control group, the following results were obtained. 1. After 2 weeks, there was no increase of mandibular size in experimental group over that of the control group. 2. After 4 weeks, the size of the condylar head was larger in experimental group than that of the control. 3. In 2 week group, the thickness of the mitotic compartment and hypertrophic chondroblastic layer was increased in experimental group. 4. In 4 week group, the number and the size of the hypertrophic chondroblasts were increased significantly on experimental group over that of the control group. 5. The application of the satanic current caused an increase in chondrocytic hypertrophy and intercellular matrix in both groups.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권2호
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• pp.106-111
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• 1998

The aim of this article was to examine the usefulness of costochondral graft in the temporomandibular joint reconstruction. We performed costochondral grafting in the mandibular reconstruction including condyle replacement in 3 patients, which 2 of ankylosed cases and 1 destructed case. In one case, unexpected fracture of costochondral junction has developed at post-operative 2 months, but, normal mouth opening and facial appearance have been acheived by continuing exercise. These patients showed maximum mouth opening of 35-40 mm and no restriction of lateral side movement. They have been improved esthetics and function. We proposed that the costochondral graft is one of the useful method for functional reconstruction of defected mandibular condyle.

• Imaging Science in Dentistry
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• 제39권4호
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• pp.205-208
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• 2009

Aneurysmal bone cyst (ABC) is relatively rare, non-neoplastic expansile lesion of bone. The case of a IS-year-old male with a ABC of the left mandibular condyle is presented. Panoramic radiograph showed a unilocular radiolucency with thinned coritces and a subcondylar fracuture which was due to the trauma. Computed tomography (CT) revealed expansile lesion which had similar attenuation soft tissue. The patient was treated surgically including iliac crestal bone graft.

• Archives of Plastic Surgery
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• 제33권6호
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• pp.792-796
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• 2006

Purpose: After exposure of fracture site, the proximal segment must be reduced to their preinjury position for open reduction of fractured mandibular condyle. We examined the use of inter-maxillary fixation screws or titanium screws tied with stainless steel wire to assist in positioning of proximal segment. Since it enables to make a relatively small preauricular incision by not disturbing the operative field like Moule pin, we can reduce the danger of injury to the facial nerve. Methods: A preauricular approach was used for exposure, reduction, and rigid fixation in 4 cases of mandibular condylar fractures. Inter-maxillary fixation screws or titanium screws tied with stainless steel wire were used to assist in aligning proximal segment. The joints were submitted to functional exercises and postoperative radiologic and clinical follow-ups were performed. Results: No facial nerve lesions were found in all 4 cases. Radiologic follow-up showed correct reduction and fixation in all 4 cases. Clinical follow-up showed an initial limitation, but normal morbility of the condyle was achieved within 4 months after the operation, with a maximum mouth opening of $34.1{\pm}5.2mm$ after 12 months. There found no occlusal disturbances, no trismus, no lateral deviations of the mandible. Conclusion: By using Inter-maxillary fixation screws tied with stainless steel wire, it was shown that reducing the proximal segment to their preinjury position is easy to perform and it enables us to make a minimal dissection below preauricular skin incision to avoid facial nerve injury.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권1호
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• pp.43-52
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• 2010

Purpose: To research about maxillofacial traumatic injuries of children in aspects of gender difference, various incidence rates between age, trauma type, cause, monthly and daily incidence rate, type of tooth damage, gingival damage, soft tissue damage, and type of facial bone fracture. Materials and methods: Study group consisted of children under 15 years of age who visited Dental Hospital, School of Dentistry, Kyung Hee University from 2004/7/1 to 2007/6/30 with chief complaint of oral and maxillofacial traumatic injuries. 1,559 cases of traumatic injuries were studied from 1,556 (1,004 male, 552 female) children. Conclusion: 1. There were slightly more boys than girls, giving a male-to-female ratio of 1.82:1.0. The 1-3 year old boys and girls had the highest number of traumatic injuries. 2. Of the 1,556 patients, 68.63% had soft tissue injuries, 50.22% had periodontal injuries, 29.89% had teeth injuries, and 3.85% had maxillofacial bone fractures. 3. Falling down was the most common cause of injury in both sexes. 4. The months with the highest incidence rates were in order May (12.12%), June (11.74%), and October (11.13%). Most of the injuries occurred on weekends. 5. The most common tooth injury was uncomplicated crown fracture, and the most common periodontal injury was subluxation. The majority of traumatizes teeth were the upper central incisors. 6. The most common soft tissue injury was intraoral lacerations. 7. Mandibular fractures were most frequent in facial bone fractures; symphysis, condylar head, and angle fractures were most frequent in mandibular fractures; maxillary and nasal bone fractures were most frequent in midfacial bone fractures.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권2호
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• pp.137-143
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• 1991

악안면부의 기형은 기능 및 심미적인 매우 중요한 문제이며, 이러한 면에서 현대 악안면 영역의 성형술은 기능 및 사회심리적으로 많은 기여를 한다는 것은 사실이다. 악안면 성형술 중 하악 우각부에 대한 관심은 19 세기 후반부터 교근비대증 (Masseter Hypertrophy)으로 표현되었으며, 안모의 심미적인 영향에 대한 평가는 동양에서 하악골의 변형과 함께 비중있게 다루어지고 있다. 교근비대 또는 협부비대의 원인은 악성 및 양성종물, 악습관에 의한 생리적 비대, 감염, 선천적기형 등이 있을 수 있으나, 환자가 호소하는 주소는 안연의 비대칭 또는 사각형의 안모등이므로 이에 대한 수술의 주된 목적은 심미적인 면이 대부분을 차지한다고 볼 수 있다. 그러므로 안모개선 등 수술 후의 결과에 대한 깊은 관심이 요구되며, 따라서 혈종이나 감염, 하악골 골절, 개구장애 등과 같은 합병증과 후유증에 대한 올바른 이해와 최대한의 예방이 필요할 것으로 사료되어 문헌고찰과 함께 증례보고를 하는 바이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권6호
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• pp.544-558
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• 2006

Trismus is a common problem to most people experiencing at once in his or her life and to most dental practitioners experiencing frequently. It has a number of potential causes which are single factor or complex factors. Its treatment will depend on the cause. The purpose of this study was to discuss the causes of trismus condition and the various treatments available. This study was made by reviewing of collected data from 86 patients complained of trismus among patients who were diagnosed by TMD, tumor, infection including tetanus, soft tissue anomalies, bony fracture and ankylosis from Jan 2002 to Dec 2004 on department of oral and maxillofacial surgery at Pusan National University Hospital, South Korea. The clinical reviews regarding chief complaints, clinical characteristics, diagnostic examination, treatments and the results on the patients were given as follows. 1. The etiology of trismus commonly were derived from temporomandibular joint(TMJ) disorder, TMJ ankylosis, TMJ tumor, odontogenic maxillofacial infection, mandibular condylar fracture, tetanus. 2. The chief complaints of trismus patients were progressive mouth opening limitation, TMJ pain, malocclusion, facial asymmetry, retrognathic state. 3. Especially, for the differential diagnosis between the fibrous ankylosis and true bony ankylosis, computed tomogram (CT) was useful. Surgical gap arthroplasty on bony ankylosis patients was applied and the gain of mouth opening after operation was average 35.8 mm during 19 months. 4. The tetanus, rarely, also induced the trismus with the range of mouth opening less than 10 mm. The average serum level of tetanus anti-toxin was 0.02-0.04 IU/mL. The limitation of mouth opening was improved into average 38 mm on 4 weeks after injection of 10,000 units of tetanus immune globulin. 5. In the treatment of osteochondroma, TMD, odontogenic infection and fracture, and the others inducing trismus, to obtian the maximum result and decreased inadequate time and effort, it is important to finding the causes from the exact clinical examination and diagnosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권5호
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• pp.567-571
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• 2007

Lateral pharyngeal space is one of potential fascial planes of head and neck, that may become involved by various pathological processes, such as infection, inflammation and neoplasm. The calcified stylohyoid ligament with styloid process is also located in this space, so this space is more acquainted with Eagle's syndrome in oral and maxillofacial field. During the mandibular transbuccal fixation procedures of 29-year old female patient who had right condylar neck and left parasymphysis fracture, we had lost one 10.0 mm miniscrew. After confirming the location of the lost miniscrew from different angled plain skull radiographies, we tried to find it in the lateral pharyngeal space via transtonsillar approach at the time of plate removal operation. This case report is aimed to share our valuable experience of the effective approach way to the lateral pharyngeal space, which has many advantages, such as short operative time, minimal bleeding, fast post-operative recovery, and less morbidity. The related literature is also reviewed.