• Journal of International Society for Simulation Surgery
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• v.2 no.2
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• pp.90-93
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• 2015

The fibula free flap has now become the most reliable and frequently used option for mandible reconstruction. Recently, three dimensional images and printing technologies are applied to mandibular reconstruction. We introduce our recent experience of mandibular reconstruction using three dimensionally planned fibula free flap in a patient with gunshot injury. The defect was virtually reconstructed with three-dimensional image. Because bone fragments are dislocated from original position, relocation was necessary. Fragments are virtually relocated to original position using mirror image of unaffected right side of the mandible. A medical rapid prototyping (MRP) model and cutting guide was made with 3D printer. Titanium reconstruction plate was adapted to the MRP model manually. 7 cm-sized fibula bone flap was designed on left lower leg. After dissection, proximal and distal margin of fibula flap was osteotomized by using three dimensional cutting guide. Segmentation was also done as planned. The fibula bone flap was attached to the inner side of the prebent reconstruction plate and fixed with screws. Postoperative evaluation was done by comparison between preoperative planning and surgical outcome. Although dislocated condyle is still not in ideal position, we can see that reconstruction was done as planned.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.135-142
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• 1992

This study was performed to define the anatomical position of the mandibular canal and the findings during the sagittal split ramus osteotomy of the mandible. The mandibles of 20 adult Korean were used. The dimension of mandibular canal from the mandibular foramen to the 1st molar was measured at 4 specific coronal-sectional location by CT scan. The results were as follows ; 1. The distance from the mandibular canal to the medial aspect of the buccal cortical plate was greatest($4.5{\pm}1.1mm$) at 2nd molar area and was not significantly greater than at any other section. 2. Buccal cortex was thickest($3.8{\pm}0.9mm$) at 2nd molar and thinnest ($2.5{\pm}0.3mm$) mandibular foramen um 3. The distance from the mandibular canal to the medial aspect of the lingual cortical plate was not significant at any sections. 4. The distance from the mandible canal to the inferior border of mandible was greatest at the mandibular foramen($20.7{\pm}3.9mm$). The canal was located more closely to the inferior border at 1st, 2nd molar area 5. The diameter of the mandibular canal was between $2.5{\pm}0.3mm$ and $2.8{\pm}0.6mm$. 6. The total mandibular thickness was greatest($21.1{\pm}2.6mm$) at 2nd molar area and narrowest($17.2{\pm}3.2mm$) at mandibular foramen area.

• Korean Journal of Cleft Lip And Palate
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• v.5 no.1
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• pp.27-42
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• 2002

This study was designed to evaluate the morphology and the position of the mandible in the complete unilateral cleft lip and palate patients, Craniofacial skeletal morphology pattern was analyzed on the lateral cephalometric radiographs of the 50 subjects of complete unilateral cleft lip and palate, the 50 normal and 50 class III, Each group was divided into child and adult sub-groups, All the data were tested statistically. The results were as follows: I, In the comparison with the normal group, complete cleft group showed smaller angular, condylar length, clockwisely rotated mandible and larger NMe/SGo(p<0.01). 2, In the comparison with the class III group, the complete cleft group showed significantly smaller angular, condylar, ramal, body length of the mandible(p<0,01). 3. As for the position of the mandibular condyle to the cranial base, the class III group was the most anterior, the normal group was the most posterior and the complete cleft group was in the middle(p<0.05). 4. In the comparison with child group, the normal adult group showed smaller mandibular angle and mandibular plane angle, but not the other two groups. And the complete cleft group and the class III group showed the similar change. The normal and class III group showed increased XiCd/XiPog, but not the complete cleft group(p<0.01).

• The korean journal of orthodontics
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• v.52 no.5
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• pp.362-371
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• 2022

Orthognathic surgery is the primary treatment option for severe skeletal discrepancy. However, orthodontic camouflage should be considered as an alternative treatment option, considering the risks of surgery. A 19.5-yearold man presented with a severe prognathic mandible with a Class III molar relationship and an anterior crossbite. Orthognathic surgery could be considered because of his severe skeletal discrepancy and mandibular prognathism. However, the anesthetist for orthognathic surgery did not recommend surgery under general anesthesia because of risk factors associated with the patient's aplastic anemia, including bleeding and infections. Thus, a camouflage treatment to promote backward rotation of the mandible via orthodontic extrusion of the posterior teeth was planned. An anterior bite plate, intermaxillary elastics, and fixed orthodontic appliances were used to extrude the posterior teeth and to align the dentition. After 17 months of nonsurgical orthodontic treatment, normal occlusion was achieved, and the facial profile was dramatically improved. This case report describes the dentoskeletal and soft-tissue effects of mandibular rotation and its long-term stability.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.2
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• pp.57-61
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• 2014

Bisphosphonate is used widely for osteoporosis treatment, but a rising concern is the risk of osteonecrosis after long-term bisphosphonate use. Such cases are increasing, suggesting a need for research to prevent and treat bisphosphonate-related osteonecrosis of jaws. A 63-year-old female took bisphosphonate (Fosamax$^{(R)}$) for four years for treatment of osteoporosis and stopped medication two months ago because of unhealed wound. She was treated with marginal mandibulectomy maintaining the inferior border, and a metal plate was placed to prevent mandible fracture. Four months after the mandibulectomy, mandible reconstruction surgery using iliac bone and allograft was done. Six months after reconstruction, implant placement and treatment with an overdenture was done without complications. This study presents a case with a successful result.

• The Journal of the Korean dental association
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• v.22 no.11 s.186
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• pp.973-978
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• 1984

The authors observed a case of Burkitt's lymphoma, occurred in the mandible, of 6-year-old female patient who admitted to the Department of Oral Radiology, Kyung Hee University Medical Center. The serial radiograms, clinical findings, and microscopid findings had been taken and obtained following results: 1. In serial radiograms, invasive and infiltrative bone destruction in the both mandibular body region was observed. Perforation and erosion of cortical plate of the mandibular angle area and loss of alveolar lamina dura in involved teeth were also noticed. 2. In microscopic findings, a monotous overgrowth of undifferentiated monomorphic lymphoreticular cells found. Macrophages with and abundant clear cytoplasm are usually found scattered uniformly throughout the tumor, producing the very characteristic 'starry-sky' appearance.

• Imaging Science in Dentistry
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• v.40 no.3
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• pp.149-153
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• 2010

Brown tumor is usually diagnosed at the terminal stage of hyperparathyroidism. Diagnosis of this tumor is confirmed by endocrinologic investigations along with clinical and radiographic examination. Radiographical differential diagnosis of this tumor includes central giant cell granuloma, aneurysmal bone cyst, metastatic tumor, multiple myeloma, and Paget disease. This report presents a rare case of multiple brown tumors occurring at the maxilla and mandible, which was initially misdiagnosed as central giant cell granuloma. Plain radiographs demonstrated multiple well-defined multilocular radiolucency. CT images showed soft tissue mass with low attenuated lesions, perforation of the lingual cortical plate, and a heterogeneous mass at the right thyroid lobe. These findings were consistent with parathyroid adenoma. The patient had hypercalcemia, hypophosphatemia, and elevated alkaline phosphatase level. Surgical excision of the tumor was performed. No recurrence was observed during a 28-month follow-up.

• The korean journal of orthodontics
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• v.46 no.6
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• pp.372-378
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• 2016

Objective: The purpose of the present study was to evaluate the postoperative three-dimensional (3D) changes in the proximal segments after mandibular setback sagittal split ramus osteotomy and to compare the changes between the conventional mini-plate fixation and semi-rigid sliding plate fixation. Methods: Cone-beam computed tomography (CBCT) images were used to evaluate the postoperative 3D changes in the proximal segments during the healing process. CBCT images were superimposed using the symphysis and the lower anterior mandible as references. Results: There were no statistically significant differences between the conventional mini-plate and semi-rigid sliding plate groups (p > 0.05). With respect to the distribution of changes greater than 2 mm in the landmarks, the right condylion, right coronoid process, and left condylion showed ratios of 55.6%, 50.0%, and 44.4%, respectively, in the semi-rigid sliding plate group; however, none of the landmarks showed ratios greater than 30% in the conventional mini-plate group. Conclusions: There were no statistically significant differences in postoperative changes in the segments between the conventional mini-plate and semi-rigid sliding plate groups. Nevertheless, while selecting the type of fixation technique, clinicians should consider that landmarks with greater than 2 mm changes were higher in the semi-rigid sliding plate group than in the conventional mini-plate group.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.2
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• pp.127-135
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• 2009

Objectives : The titanium fixation system has been used in orthognathic surgery for fixation of bone segments usually, but the biodegradable fixation system was developed and also being used. The strongest point in the biodegradable system is that no extra operation should be needed to remove fixation materials. In spite of this merit, oral & maxillofacial surgeons hesitate to use this system in fracture or orthognathic surgery. In this study, as we got some clinical experiences, we'd like to report the result of clinical study using the biodegradable fixation system in orthognathic surgery. Patients and Methods : A total of 35 patients composed of 17 males and 18 females with 25 osteotomies in maxilla and 34 osteotomies in mandible were fixated with the biodegradable fixation system(Inion $CPS^{(R)}$). We investigated methods of stabilization, fixation time, and complications on the basis of the method as above. Results : Four 2mm thick L shaped plates with 7 holes of which 1 hole was removed were fixed in maxilla with six $2.0{\times}7mm$ screws. Three $2.5{\times}16{\sim}18mm$ screws were used to fix superior ramus area and one mandibular angle area in mandible. It took about 27.4 minutes in maxilla, 25.3 minutes in mandible to perform the fixation which took longer time than the titanium system(9.5 minutes in maxilla, 8 minutes in mandible). Generally, there was no problem except 9 cases in which there were some complications. Conclusions : In most cases, the biodegradable fixation system can be used without problem in usual orthognathic surgery. But, this system is inferior to the titanium fixation one in some respects such as fixation time, size, and physical property. Some supplementations for such weak points as aforementioned should be needed for the universal use of biodegradable materials.

• The korean journal of orthodontics
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• v.47 no.5
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• pp.289-297
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• 2017

Objective: The objective of this study was to analyze the patterns of tooth movements when distalization of mandibular molars using a mini-plate took place. A finite element analysis was applied to analyze patterns of tooth movements. Methods: The model of the mandible and teeth were used to build a finite element analysis model, and a mini-plate was inserted in the mandibular ramus. Two different orthodontic forces were established for displacement of mandibular molars. Orthodontic forces were applied at the level of the bracket and at the level of the cemento-enamel junction in the mandibular canine respectively. Results: Applying orthodontic forces at the level of the cemento-enamel junction resulted in a greater biomechanical bodily movement in distalization of the mandibular molars compared to when the orthodontic forces were applied at the level of the bracket. Applying orthodontic forces to the cemento-enamel junction also resulted in unwanted greater extrusive movements in distalization of the mandibular molars compared to the bracket level. Conclusions: With considering the mode of orthodontic teeth movement, applying different vertical orthodontic forces for distalization of mandibular molars can lead to more effective distalization of teeth.