• Journal of Welding and Joining
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• 제23권4호
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• pp.34-40
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• 2005

There have been numerous approaches to examine the bonding strengths of solder joints. However, despite the technical and practical limitations, the precedent test methods such as the ball shear and ball pull tests are being used in industrial applications. In this study, the optimum jaw pressure with the modified protrusion jaw was introduced in order to obtain higher successful rate f3r ball pull testing. Furthermore, the pull strengths and fracture modes of Sn-8Zn-3Bi, Sn-4Ag-0.7Cu, and Sn-37Pb eutectic solder after isothermal aging tests ($100^{\circ}C,\;150^{\circ}C$), were evaluated with the protrusion jaw. The pull strength-displacement hysteresis curves and fracture surfaces were carefully investigated to evaluate the correlation between the pull strengths and the fracture modes of each solder. In conclusion, it is verified that Au-Zn IMCs (Intermetallic Compounds) have a detrimental effect on the pull strengths and changed fracture modes of Sn-8Zn-3Bi solder. Meanwhile, the microstructure transformation influences the degradation of pull strengths of Sn-4Ag-0.7Cu and Sn-37Pb solders.

• 대한두개안면성형외과학회지
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• 제21권5호
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• pp.301-304
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• 2020

Orthognathic surgeries often utilize rigid fixation for stabilization of the osteotomy site. The longterm fate of rigid fixations is still under investigation, and whether they should be routinely removed is under debate despite their low complication rates. Here, we report a case where a 26-year-old man suffered high-velocity trauma to his face 7 years after a two-jaw surgery. Computed tomography examination revealed a zygomaticomaxillary complex fracture, and open reduction and internal fixation was performed along with anterior maxillary wall reconstruction using absorbable mesh. Intraoperative examination revealed a broken L-shaped titanium plate near the fracture site with multiple bony fragments near each titanium screw. The rigid titanium system may have caused comminution of the fracture pattern, worsening the severity of the fracture.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권2호
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• pp.91-95
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• 2014

The posttraumatic complications of jaw fractures related to jaw function and facial deformity include nonunion, malunion, malocclusion, temporomandibular joint dysfunction and facial asymmetry. This report presents cases referred to our department for revision of malunion and malocclusion following inadequate reduction of jaw fractures. Three patients with posttraumatic malocclusions caused by malunion were treated with a LeFort I osteotomy in one case and re-fracture in two cases. All of the patients exhibited stable results without further complications (e.g., malunion or malocclusion). Accurate preoperative diagnosis and proper anatomical reduction of the fracture segments are essential to preventing post-surgical malunion and malocclusion.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제25권4호
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• pp.356-360
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• 1999

PURPOSE : This is to review the complicated jaw fractures that had been referred for revision of the unsatisfactory results, and to provide proper managements for the easily complicated jaw fractures. MATERIALS & METHODS : Twenty-nine patients who had been revised due to malunion or complicated fractures of facial bones for last 3 years were reviewed. The main problems required for revision, type of fractures complicated, the primary managements to be reclaimed, the specialties to be involved, the management to be reclaimed, time elapsed to seek reoperation, type of revision surgeries, residual complication were analysed with medical records, radiographs and final examinations. RESULTS: The major complaints were malocclusion(79.3%), facial disfigurement(41.3%), TMJ problems (13.7%), neurologic problems(10.3%), non-union(10.3%), and infection(6.8%). Unsatisfactory results were occurred most frequently after improper management of the multiple fractures of the mandible (62.2%), combined fractures of maxilla and mandible (20.6%), fracture of zygomatico-maxillary complex and midpalate (17.2%). The complications to be corrected were widened or collapsed dental arches (79.3%), improperly reduced condyles (41.3%), painful TMJ (34.4%), limited jaw excursion (31.0%), over-reduction of zygoma (13.7%), and nonunion with infection(13.7%). and dysesthesia (10.3%). The primary managements were nendereet by plastic surgeons in 82.7%(24/29) and by oral surgeons in 7.6%(2/29). Main causes of malunion are inadequate ORIF in 76%, unawareness & delay in 17%, and delayed due to systemic cares in 17%. 76% of 29 patients had been in state of intermaxillary fixation for over 4 weeks. Revision were done by means of "refracture and ORIF"in 48.2%(14/29), orthognathic osteotomies with bone grafts in 55.1%(16/29), and camouflage countering & alloplastic implantations in 37.9%(11/29), TMJ surgeries in 17.2%, micro-neurosurgeries in 11.6%. Residual complications were limited mouth opening in 24.1% (7/29), paresthesia in 13.7%, resorption of reduced condyle in 10.3%. CONCLUSIONS : Failure of initial treatment of jaw fractures is due to improper diagnosis and inadequate treatment with lack of sufficient knowledge of stomatognathic system. It is crucial to judge jaw fracture and patients accurately, moreover, the best way of treatments has to be selected. Consideration of these factors in treatment could minimize the complication of jaw fractures.

• 한국치위생학회지
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• 제15권4호
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• pp.661-669
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• 2015

Objectives: The purpose of the study is to investigate of visiting time and major cause of disease by operating time changes of a university dental emergency room. Methods: This study was a retrospect study carried out by reviewing 9,172 records visiting the university emergency room from January 1997 to December 2009. Data were analyzed by frequency test, chi-square test, and logistic regression using SAS version 9.3. Results: Twenty four hours emergency room had 19 percent more patients than those in daytime emergency room. Daytime emergency room had more male patients during spring(26.6%) and winter(20.2%) than female patients(p<0.05). Female patients exceeded male patients during summer(24.4%) and autumn(36.2%)(p<0.05). Twenty-four hours emergency room had the maximal patients in autumn and the minimal patients in winter(p<0.05). The most common injury in the daytime was tooth fracture from 0 to 19 years old(p<0.05). Tooth fracture, jaw fracture, and soft tissue injury were the most common injury in dental emergency room and majority of the patients were the male(p<0.05). Conclusions: Twenty-four hours dental emergency room had a variety of causes of dental emergency thant that in the daytime. Twenty four hours dental emergency room must be prepared for the dental emergency patients at any time provided with personnel and facilities.

• 대한치과마취과학회지
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• 제14권4호
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• pp.233-236
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• 2014

In order to reduce jaw fracture accompanied by basal skull or nasal fracture, submental intubation could be generally performed. Albeit submental intubation has been widely accepted, it could develop complications such as nerve injury, glandular duct injury, and orocutaneous fistula. Here, we suggest oral intubation for overcoming complications and providing more stable surgical environment in emergency case. Under oral intubation maintaining in retromolar triangle and buccal corridor space, intermaxillary fixation was successfully underwent in 38-years-old female patient with Le Fort I fracture accompanied by pneumocephalus.

• 한국임상수의학회지
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• 제37권6호
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• pp.363-366
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• 2020

A 2-month-old, 50 kg male Korean native calf was referred with bilateral mandibular fractures. The bilateral mandible was hanging loose, with inability to use the jaw, indicated by excessive salivation. Radiography revealed a long oblique fracture in the right mandible, and a short oblique fracture in the left mandible. Computerized Tomography, a different form of radiography, revealed the fracture in the left mandible to be a comminuted fracture. In order to stabilize the bilateral mandible fractures, a combination of bone plate and wiring was applied; in addition, resin was applied to enhance stabilization of the mandible. Six weeks after surgery, the calf was able to masticate and ruminate well. In this case, application of the plate and wiring with resin to bilateral mandibular fractures presented a successful functional recovery. Accordingly, the combination of bone plate and wiring with resin can be an effective technique for treating mandibular fractures.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권1호
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• pp.43-48
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• 2010

The mandibular condyle fracture occurs at 15-30% frequency of whole mandibular fracture. The treatment of choice is open reduction or closed reduction. In many cases, closed reduction is preferred for treatment of condylar fracture because it is hard to approach to condyle and there is risk of surgical complications, such as nerve damage in open reduction. Open reduction, however, has some advantages like possibility of anatomical reduction, occlusal stability and rapid functional recovery. Furthermore, it is possible to retain original ramal heights and to decrease deviation during mouth opening. There are many surgical approaches for open reduction of subcondyle fracture. At present, transoral approach using trochar device is tried for effective and minimally invasive method for open reduction of subcondyle fracture. And the authors report the cases of reduction of subcondyle fracture with transoral approach using trochar device.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권5호
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• pp.201-206
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• 2014

Purpose: To establish management protocol for mandibular angle fracture, we describe pertinent factors including cause, impacted third molar and recent treatment tendency. Methods: We examined the records of 62 patients who had unilateral mandibular angle fracture. Sixty patients who had open reduction surgery were examined at postoperative weeks 1, 4, 8, 12, and 28. Results: Left mandibular angle fracture is frequent in younger males. Presence of the mandibular third molar can increase fracture risk. Because of attached muscle, favorable fractures occurred primarily in the mandibular angle area. Conclusion: Extracting the mandibular third molar can prevent angle fractures, and open reduction with only one plate adaptation is generally the proper treatment method for mandibular angle fracture.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권5호
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• pp.488-492
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• 2010

This review evaluates the literature on the relationship between mandibular condylar process fracture and temporomadibular joint (TMJ). The topic of condylar fracture generated more discussion and controversy than any other field of maxillofacial trauma associated with TMJ. Disturbance of occlusal function, devia-tion of mandible, internal derangements of TMJ, and ankylosis of the joint with resultant inability to move the jaw are sequelae of condylar process fracture. Thus it is necessary to understand how the masticatory system adapts to the structural alterations that accompany fractures of the mandibular condyle. Treatment of condylar process fracture include two methods ; closed treatment and open treatment. If one chooses totreat closed, one must understand that adaptations in the musculature, skeleton, and dentition will be necessary. Open treatment of condylar process fractures probably requires fewer adaptations within the masticatory system to provide a favorable functional outcome. However, one must weigh the risk of open surgery against the possible improvement in outcome. The risks are not just surgical risk, but biological risk as well, such as disruption of the blood supply to the condyle. This review presents relevant aspects of change of TMJ associated with condylar process fracture.