• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.533-547
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• 1999

Malignant fibrous histiocytoma is one of the most common soft tissue sarcomas in late adult life. but its incidence in oral and maxillofacial region is extremely rare. We report a case of malignant fibrous histiocytoma which occurred in the infratemporal fossa. Conventional radiograph of this case showed an ill-defined radiolucent lesion in the alveolar bone of the right maxillary first molar area. the lateral wall of the maxillary sinus. and the ascending ramus of mandible. MRI demonstrated a well defined mass of intermediate signal intensitiy in Tl weighted images but T2 weighted images showed two distinctive regions of different characteristics. Upper portion of the lesion was of hyperintense signal but (at) lower portion, the signal intensity decreased clearly, which might mean that this lesion(mass) is composed of two different subtypes though it couldn't be confirmed by histopathological examination. Biopsy was taken the lesion as only in the soft tissue of the maxillary posterior alveolar region and confirmed the storiform-pleomorphic type of malignant fibrous histiocytoma. Histopathological subtype was well consistent with the relatively aggressive imaging findings of that region. We expect more detailed analysis of the nature of malignant fibrous histiocytoma with improvement of the imaging modality and the identification of the relationship between diagnostic imaging and histopathologic findings.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.5
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• pp.298-300
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• 2003

Ameloblastomas are generally considered to be benign tumors of odontogenic epithelial origin with high local recurrence. Rarely ameloblastomas exhibit malignant behavior with development of metastases. In this report, we present a 19-year-old woman with ameloblastoma in the right ascending ramus and multiple recurrences. Eleven years after first therapy, ameloblastoma metastasized to ipsilateral submandibular lymph node. We also review literature about cause, treatment and work-up of malignant ameloblastoma.

• Journal of The Korean Dental Society of Anesthesiology
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• v.9 no.1
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• pp.24-29
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• 2009

When performing the inferior alveolar nerve block anesthesia, surgeon often faced a difficulty of the surgical operation due to the incomplete anesthesia. One of the reason is the variety of mandibular canal anatomy. Up to now, there are some reports of index cases about bifid mandibular canal among mandibular canal anatomic variation, and some classification is applied according to anatomical location and configuration. When surgical operation is performed involving mandible such as dantal implant treatment, extraction of an impacted third molar, sagittal split ramus osteotomy, etc, the position of mandibular canal should be considered. Bifid mandibular canal clinically causes troublesome cases of anesthesia when inferior alvelor nerve block, especially is performed extraction of an impacted third molar. Therefore, It is important for clinicians to recognize the presence of bifid canals on radiographys. Nowadays, the position of mandibular canal can be measured precisely by using Dental CT. It is not found by panorama image but is found by Dental CT sometimes. Among the patients, which take panorama and Dental CT simultaneously, for tooth extraction of lower impacted third molar in our department, we report the case that did not identifying in panorama but identifying it in Dental CT.

• Imaging Science in Dentistry
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• v.32 no.2
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• pp.89-97
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• 2002

Purpose: The objective of this study is to find the differentiating characteristics of ameloblastomas and odontogenic keratocysts of the jaw by analyzing computed tomography (CT) images of the lesions, clarify radiological characteristics associated with jaw lesions, and to make a diagnsis based on these findings. Materials and Methods : Test subjects were chosen among the patients who were diagnosed as having an odontogenic keratocyst or ameloblastoma at the Yonsei University Dental Hospital from January 1996 to December 2000 and had CT scans taken preoperatively. The subject pool was comprised of 51 cases of odontogenic keratocyst and 37 cases of ameloblastoma. The following measures were used for image analysis of the lesion: the anatomic location, CT pattern, mesiodistal width, buccolingual width, the ratios between mesiodistal width and buccolingual width, height, CT number, homogeneity of radiodensity, the appearance of a sclerotic rim, continuity of adjacent cortical bone, and displacement and resorption of adjacent teeth. Results: Comparing the CT patten, mesiodistal width, buccolingual width, height, CT number, homogeneity, appearance of sclerotic rim, continuity of adjacent cortical bone, there were statistically significant differences between ameloblastoma and odontogenic keratocyst test subjects (p<0.05). Comparing the ratios between mesiodistal width and buccolingual width, displacement and resorption of adjacent teeth, there were no statistically significant differences (p>0.05). Conclusion: We compared odontogenic keratocysts and ameloblastomas in CT scans. They occurred most frequently in the posterior to the ramus of the mandible. The findings of patterns of the CT images showed that size and border of lesions were more aggressive in ameloblastomas than in odontogenic keratocysts. The internal contents represented an increased attenuation area (IAA) in odontopenic keratocyst. Odontogenic keratocysts were shown to have higher CT numbers than ameloblastomas.

• The korean journal of orthodontics
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• v.43 no.1
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• pp.42-52
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• 2013

The aim of this paper was to propose a new method of bimaxillary orthognathic surgery planning and model surgery based on the concept of 6 degrees of freedom (DOF). A 22-year-old man with Class III malocclusion was referred to our clinic with complaints of facial deformity and chewing difficulty. To correct a prognathic mandible, facial asymmetry, flat occlusal plane angle, labioversion of the maxillary central incisors, and concavity of the facial profile, bimaxillary orthognathic surgery was planned. After preoperative orthodontic treatment, surgical planning based on the concept of 6 DOF was performed on a surgical treatment objective drawing, and a Jeon's model surgery chart (JMSC) was prepared. Model surgery was performed with Jeon's orthognathic surgery simulator (JOSS) using the JMSC, and an interim wafer was fabricated. Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, and malar augmentation were performed. The patient received lateral cephalometric and posteroanterior cephalometric analysis in postretention for 1 year. The follow-up results were determined to be satisfactory, and skeletal relapse did not occur after 1.5 years of surgery. When maxillary and mandibular models are considered as rigid bodies, and their state of motion is described in a quantitative manner based on 6 DOF, sharing of exact information on locational movement in 3-dimensional space is possible. The use of JMSC and JOSS will actualize accurate communication and performance of model surgery among clinicians based on objective measurements.

• Journal of Oral Medicine and Pain
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• v.17 no.2
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• pp.63-73
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• 1992

This study was performed for the purpose of investigating the relation between width of temporomandibular joint space and craniofacial morphology in patients with CMDs. The subjects utilized here were aged from 16 to 63 years old and 19 male and 46 female. For the study, each patient was taken radiographs by Transcranial and Lateral Cephalographic projection and the films were traced with routine method. The measured items were anterior, superior, posterior joint space and relative condylar position to the deepest part of glenoid fossa in Transcranial film and items related vertical and/or horizontal growth in Cephalogram. The data were processed with SPSS/PC+ package for statistical analysis. The obtained results were as follows : 1. Anterior joint space in affected side were wider than that of unaffected side, but for superior and posterior joint space, the value of unaffected side were more than those of affected side. 2. Superior or posterior joint space of affected side were significantly correlated with items related vertical growth, such as ramus height, Jarabak ratio, FMA. From this, the following cold be proposed, the wider the joint space of superior or posterior aspect of affected side was, the more the patient showed growth pattern of counter clockwise. 3. Superior or posterior joint space of affected side were significantly correlated with items related horizontal growth, such as SNPo, NAPo, APDI and ANB. From this the following could be proposed, the wider the joint space of superior or posterior aspect of affected side was, the more the patient showed anterior displacement of mandible. 4. It would be proposed that the diagnositic value of superior and posterior joint space of affected side in transcranial radiograph was excellent.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.294-305
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• 2009

Purpose: This retrospective study evaluated the changes in hyoid bone and tongue positions as well as oral cavity volume after mandibular setback by BSSRO. Materials and Methods: 18 Koreans who underwent BSSRO to correct mandibular prognathism were studied. Lateral cephalograms were taken and traced preoperatively (T0), immediately (T1) and approximately 6 months postoperatively (T2). Submentovertex radiograghs were taken and traced before surgery (T0) and about 6 months after surgery (T2). The area and volume of oral cavity, the vertical and horizontal dimensions of the hyoid bone and tongue dorsum were measured. Results: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume. The hyoid bone displaced posteroinferiorly immediately after surgery, and it tended to return to its original vertical position at 6 month after mandibular setback by BSSRO. The retropalatal space around tongue was maintained and the retrolingual space around tongue was reduced immediately postoperatively. The readaptation of tongue was not evident for that the follow up period was not long enough. No significant statistical correlations between the amounts of mandibular setback and the changes of oral cavity volume were observed. Conclusion: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume, which was most likely attributable to the posterior movement of the mandible. More subjects and long-term observations should be performed to assess the changes of oropharyngeal configuration following mandibular setback surgery.

• The korean journal of orthodontics
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• v.50 no.2
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• pp.136-144
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• 2020

Hemifacial microsomia (HFM) patients may experience emotional withdrawal during their growth period due to their abnormal facial appearance. Distraction osteogenesis at an early age to improve their appearance can encourage these patients. Some abnormalities of the affected side can be overcome by distraction osteogenesis at an early age. However, differences in the growth rate between the affected and unaffected sides during the rest of the growth period are inevitable due to the characteristics of HFM. Therefore, re-evaluation should be performed after completion of growth in order to achieve stable occlusion through either orthognathic surgery or camouflage orthodontic treatment. An eight-year-old patient visited the clinic exhibiting features of HFM with slight mandibular involvement. He received phase I treatment with distraction osteogenesis and a functional appliance. Distraction osteogenesis was performed at the right ramus, which resulted in an open bite at the right posterior dentition. After distraction osteogenesis, a functional appliance and partial fixed appliance were used to achieve extrusion of the affected posterior dentition and settlement of the occlusion adjustment on the unaffected posterior dentition. The patient visited the clinic regularly for follow-up assessments, and at the age of 20 years, he showed facial asymmetry of the mandible, which had deviated to the right side. He received orthodontic treatment to improve the occlusion of his posterior dentition after the growth period. Without orthognathic surgery, stable occlusion and a satisfactory facial appearance were obtained through camouflage orthodontic treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.5
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• pp.444-450
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• 2007

In general, labiolingual or buccolingual widths of residual alveolar bone are insufficient in edentulous area, because of alveolar resorption. Horizontal augmentation is bone graft procedure with a view to reinforcing horizontally insufficient bone quantity for installation of implants. The standard method is taking appropriate amount of block bone from intraoral or extraoral autogenous bone, and solid fixation with screws or mini-plate on labial or buccal side of residual alveolar bone. The purpose of this study is to discuss clinical usefulness of horizontal augmentation with autogenous block bone by observation and analysis of course of 41 implants installed to 12 patients by horizontal augmentation in Seoul National University Bundang Hospital from July, 2002 to December, 2005. The mean age of patients is 52.7, from 19 to 70, and the number of men and women is each 2 and 10. Block bone was taken from symphysis, body, ramus of mandible or iliac bone. And 6 types of implants were installed simultaneously or not, the diameters of implants are from 3.3 to 5.5mm, the lengths are from 8 to 15mm. The operator added artificial bone grafting material and optionally covered with membrane. The mean periods of observation after operation and final prosthetics were 28.6 and 17.0 months. As a result, 40 among 41 implants survived, the survival rate was 97.6%. Average 0.9mm crestal resorption was observed at final point of time by periapical view of each patients. Major complication related to the procedure was numbness in 7 patients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.5
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• pp.365-372
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• 2021

Objectives: Mandibular fractures vary significantly with respect to epidemiological and demographic parameters among populations. To date, no study has evaluated these aspects of mandibular fractures in Nuh, Mewat, Haryana, India. To retrospectively analyze the incidence, age and sex distributions, etiology, anatomic distribution, occlusal status, treatment modality provided, and their correlation in patients who suffered isolated mandibular fractures. Materials and Methods: The records of maxillofacial injury patients who reported to the Department of Dentistry, SHKM Government Medical College from January 2013 to December 2019, were retrieved from our database, and necessary information was collected. The data collected were analyzed statistically using IBM SPSS ver. 21. Results: Totals of 146 patients and 211 fractures were analyzed. There were 127 males and 19 females with an age range of 3-70 years (mean age, 26 years). Road traffic accident (RTA) was the most common cause of fracture (64.4%), followed by fall (19.9%), assault (15.1%), and sports injury (0.7%). Of all patients, 42.5% had bilateral fractures, 31.5% had left side fracture, 21.2% had right side fracture, 3.4% sustained midline symphyseal fracture, and 1.4% had symphyseal fracture along one side of the mandible. Site distribution was as follows: parasymphysis (34.6%), angle (23.7%), condyle (20.4%), body (12.8%), symphysis (4.3%), ramus 2.4%, and dentoalveolar 1.9%. The most common facture combination was angle with parasymphysis (17.8%). Occlusion was disrupted in 69.2% patients. Closed reduction was the predominant treatment modality. Conclusion: The data obtained from retrospective analyses of maxillofacial trauma increase the understanding of variables and their outcomes among populations. The results of the present study are comparable to those of the literature in some aspects and different in others.