• The korean journal of orthodontics
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• v.54 no.2
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• pp.128-135
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• 2024

Objective: The number of three-piece maxillary osteotomies has increased over the years; however, the literature remains controversial. The objective of this study was to evaluate the skeletal stability of this surgical modality compared with that of one-piece maxillary osteotomy. Methods: This retrospective cohort study included 39 individuals who underwent Le Fort I maxillary osteotomies and were divided into two groups: group 1 (three pieces, n = 22) and group 2 (one piece, n = 17). Three cone-beam computed tomography scans from each patient (T1, pre-surgical; T2, post-surgical; and T3, follow-up) were used to evaluate the three-dimensional skeletal changes. Results: The differences within groups were statistically significant only for group 1 in terms of surgical changes (T2-T1) with a mean difference in the canine region of 3.09 mm and the posterior region of 3.08 mm. No significant differences in surgical stability were identified between or within the groups. The mean values of the differences between groups were 0.05 mm (posterior region) and -0.39 mm (canine region). Conclusions: Our findings suggest that one- and three-piece maxillary osteotomies result in similar post-surgical skeletal stability.

• The korean journal of orthodontics
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• v.54 no.4
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• pp.247-256
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• 2024

Objective: This retrospective study evaluated the mandibular condyle position before and after bimaxillary orthognathic surgery performed with the mandibular condyle positioned manually in patients with mandibular prognathism using cone-beam computed tomography. Methods: Overall, 88 mandibular condyles from 44 adult patients (20 female and 24 male) diagnosed with mandibular prognathism due to skeletal Class III malocclusion who underwent bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I performed using the manual condyle positioning method were included. Cone-beam computed tomography images obtained 1-2 weeks before (T0) and approximately 6 months after (T1) surgery were analyzed in three planes using 3D Slicer software. Statistical significance was set at P < 0.05 level. Results: Significant inward rotation of the left mandibular condyle and significant outward rotation of the right mandibular condyle were observed in the axial and coronal planes (P < 0.05). The positions of the right and left condyles in the sagittal plane and the distance between the most medial points of the condyles in the coronal plane did not differ significantly (P > 0.05). Conclusions: While the change in the sagittal plane can be maintained as before surgery with manual positioning during the BSSRO procedure, significant inward and outward rotation was observed in the axial and coronal planes, respectively, even in the absence of concomitant temporomandibular joint disorder before or after the operation. Further long-term studies are needed to correlate these findings with possible clinical consequences.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.50 no.4
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• pp.227-234
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• 2024

In patients with unilateral mandibular condyle hyperplasia, whether to perform condylectomy and orthognathic surgical procedures at the same time or orthognathic surgery in two stages for remains controversial. Reported here is a case of facial asymmetry with mandibular condyle hyperplasia, for which condylectomy and orthognathic surgery procedures were performed at the same time. A 28-year-old woman was presented to our department with chief complaints of left deviation of the mandible and right temporomandibular joint (TMJ) noise. Findings obtained in several imaging examinations led to a diagnosis of facial asymmetry associated with right mandibular condyle hyperplasia. Following 3 months of preoperative orthodontic treatment, in October 2018 under general anesthesia the patient underwent a right mandibular condylectomy, Le Fort I osteotomy, right mandibular sagittal split ramus osteotomy, and left mandibular inverted L ramus osteotomy. In examinations up to 3 years after surgery, good results were noted. For this case of severe facial asymmetry with mandibular condyle hyperplasia, early surgery and condylectomy were performed simultaneously to significantly shorten the total treatment time. The effectiveness of a surgery-early approach was confirmed by no postoperative findings indicating abnormalities in the TMJ or retroversion.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.50 no.4
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• pp.235-240
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• 2024

Lipomas, the most common soft-tissue mesenchymal neoplasms in adults, are characterized by the proliferation of mature white adipocytes without cytologic atypia. Lipomas are rarely observed in the head and neck region. We present a case of resection and orthognathic surgical removal of an intramuscular lipoma of the mandible with involvement of the mandibular ramus and condylar head and neck. An 18-year-old female patient was referred to our hospital for orthognathic surgery for the management of facial asymmetry and mandibular prognathism. The patient did not present with facial swelling, pain, or temporomandibular dysfunction; however, on radiographic examination, including cone-beam computed tomography and magnetic resonance imaging, an infiltrative fatty lesion was observed in the masticator space inside the right mandible, and the adjacent mandible exhibited bone thinning and deformity. Resection of the lipoma was performed along with orthognathic surgery, including a Le Fort I osteotomy for the maxilla and bilateral sagittal split ramus osteotomy (BSSRO). In this case, because the ramus was split using BSSRO, accessing the lipoma intraorally was easy. Consequently, aesthetic scarring was avoided, and no complications, such as unfavorable splitting or pathologic fracture, occurred. Although recurrence has not been observed about 1 year, long-term follow-up should be performed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.6
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• pp.644-651
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• 2000

In cases of severe alveolar bony resorption in the edentulous posterior maxillae, implant placement is limited anatomically due to maxillary sinus. If the ridge is atrophic, the various bone grafting methods are required for the ridge augmentation. But the result of the onlay grafting procedure is not always promising. On the posterior maxilla, maxillary sinus mucosa lifting and bone grafting into the sinus floor, subantral augmentation(SA) technique are recommended. Various SA procedures have been developed for implant installation. We perfer to simultaneous block bone graft and implant installation through the residual alveolar ridge into the grafted block bone to fix the grafted bone and to gain the primary stability of the installed fixture. When a sagittal skeletal discrepancy in present due to the severe alveolar bony resorption of the maxilla, the advancement of the maxilla by Le Fort I osteotomy simultaneously with installation of implant fixtures combined with sinus lifting and interpositional bone graft procedure can be indicated. We applied various SA techniques for implant installtion to the 46 edentulous posterior maxillae, and total 154 implants were installed at our department from 1992 to 1999. Various SA techniques were classified in detail and the indications of each techniques were discussed. The changes of residual bony height following SA procedure were studied. The results were as follows. 1. The SA procedure combined with bone graft and simultaneous fixture installation were performed in 41 cases, 126 fixtures were installed and 5 fixtures were removed out of them. Le Fort I osteotomy procedure combined with sinus lifting and interpositional bone graft simultaneous with fixture installation were performed in 5 cases. Total 28 fixtures were installed and 2 fixtures were removed so far. 2. Autogenous block bone graft into sinus floor were performed in 35 cases, autogenous particulated marrow cancellous bone(PMCB) graft in 9 cases, and demineralized human bone powder in 2 cases. The donor site for bone graft were anterior iliac bone in 39 cases, posterior iliac bone in 3 cases and mandibular symphysis in 1 case and mandibular ramus in 1 case. 3. In 9 cases with which SA procedure had been performed with the block bone graft, the change of pre- and postoperative residual bony height were measured using MPR(multiplanar reformatted)-CT. The mean residual bony height was 8.0mm preoperatively, 20.2mm at 6 months following up operation and we gained average 12.2mm alveolar bony height. So, we can recommend this one-stage subantral augmentation and fixture installation technique as a time conserving, safe and useful method for compromised posterior edentulous maxilla.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.3
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• pp.359-371
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• 2010

Facial asymmetry has been found with a higher frequency (70~84%) in skeletal class III malocclusion patients. Anticipating the poor prognosis of prosthesis due to malocclusion, occlusal stability must be obtained by orthodontic treatment. Moreover, orthodontic surgery would be needed in some severe cases for better functional and esthetic results. The orthognathic surgery is performed on one jaw or two jaw depending on the results of facial diagnosis. Genioplasty may change the vertical, horizontal, sagittal position of chin by osteotomy or augmentation using implants, also. This case is about a 24 year-old male patient who visited our clinic to solve the facial asymmetry and mandibular prognathism. Skeletal class III malocclusion, maxillary canting and menton deviation to left by 13 mm were detected. Multiple ill-fitting prostheses, unesthetic maxillary anterior prostheses, and several dental caries were found. After pre-operative orthodontic treatment, Le-Fort I osteotomy, sagittal split ramus osteotomy, genioplasty, right mandibular angle augmentation were done for the correction of jaw relation and asymmetry. By diagnostic wax-up after post-operative orthodontic treatment, maxillary full mouth rehabilitation and mandibular posterior restorations were planned out. For better result, clinical crown lengthening procedure was done on #11, 12 and implant was placed on left mandibular first molar area. The patient was satisfied with the final prostheses. Because of his high caries risk, long-term prognosis will depend on the consistent maintenance of oral hygiene and periodic follow-up.

• The korean journal of orthodontics
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• v.50 no.5
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• pp.336-345
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• 2020

Objective: To investigate the treatment modalities (Tx-Mods) for patients with unilateral hemifacial microsomia (UHFM) according to Pruzansky-Kaban types and growth stages. Methods: The samples consisted of 82 Korean UHFM patients. Tx-Mods were defined as follows: Tx-Mod-1, growth observation due to mild facial asymmetry; Tx-Mod-2, unilateral functional appliance; Tx-Mod-3, fixed orthodontic treatment; Tx-Mod-4, growth observation due to a definite need for surgical intervention; Tx-Mod-5, unilateral mandibular or bimaxillary distraction osteogenesis (DO); Tx-Mod-6, maxillary fixation using LeFort I osteotomy and mandibular DO/sagittal split ramus osteotomy; Tx-Mod-7, orthognathic surgery; and Tx-Mod-8, costochondral grafting. The type and frequency of Tx-Mod, the number of patients who underwent surgical procedures, and the number of surgeries that each patient underwent, were investigated. Results: The degree of invasiveness and complexity of Tx-Mod increased, with an increase in treatment stage and Pruzansky-Kaban type (initial < final; [I, IIa] < [IIb, III], all p < 0.001). The percentage of patients who underwent surgical procedures increased up to 4.2 times, with an increase in the Pruzansky-Kaban type (I, 24.1%; IIa, 47.1%; IIb, 84.4%; III, 100%; p < 0.001). However, the mean number of surgical procedures that each patient underwent showed a tendency of increase according to the Pruzansky-Kaban types (I, n = 1.1; IIa, n = 1.5; IIb, n = 1.6; III, n = 2.3; p > 0.05). Conclusions: These findings might be used as basic guidelines for successful treatment planning and prognosis prediction in UHFM patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.3
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• pp.247-258
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• 1994

We got this conclusion from an investigation about complications from 144 cases of 130 patients who were to be searched their personal records, admission chart, clinical laboratory sheet, anesthetic record, consult sheet and radiographic opinion. They had orthognathic surgery for maxillofacial deformity treatment at the department of oral and maxillofacial surgery in dental school of Kyung Hee university for 4 years and 10 months, from March 1989 to December 1993. 1. In the intraoperative phase, by the frequency of complication, blood vessel injury was found the most-22%, and then soft tissue injury, unfavorable osteotomy split, and there were some cases of tooth injury and inappropriate osteotomy. In the mandibular segmental osteotomy, blood vessel injury was found the most frequently-20 cases (27%), soft tissue injury, unfavorable osteotomy split were the second frequent cases, and then unfavorable fragment position was found. In the extraoral vertical ramus osteotomy and Le Fort I osteotomy also, blood vessel injury and nerve injury were found the most. 2. In the postoperative hospitalization phase, by the frequency of complication, hematoma (23%) was happened the most, except for that, lkie the complication that can be happened by adverse reaction of medicine or long hospital life. In the case of SSRO, there were 21 cases (20%) of hematoma, and this wal the most frequently case. In the case of EVRO, hematoma wasn't happened that much-2 case (4%). 3. In the follow up phase, relaps, numbness and TMJ dysfunction were happened. In mandibular surgery, the forward relapse percentage of point B, was 27% when used wire fixation on SSRO, was 15% by miniplate fixation on SSRO and was 7% on EVRO. In the case of SSRO, numbness was kind of high, comparing to ordinary surgery-12 cases(16 There were many difficulties in analyzing this data accurately, Although orthognathic surgery is done many times, only available date is from the "success" stories and data is not consistently recorded for the cases with complications. In this manner, much essential informantion is lost and overlooked. When data is charted including those cases that are seemingly insignificalt, we can have a much clearer understanding and more accurate guide on treatment protocols.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.4
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• pp.320-328
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• 2006

Purpose: The aim of this study was to evaluate the effects of pterygomaxillary separation on dimensional changes of dental arch following surgically-assisted rapid maxillary expansion (SARME). Patients and Methods: Eighteen adults who had been treated by SARME for transverse maxillary deficiency from May 2000 to August 2005 were evaluated. Thirteen patients (Group 1) were treated with subtotal Le Fort I osteotomy including pterygomaxillary separation and anterior midpalatal osteotomy. The same operation was performed in five patients (Group 2) except pterygomaxillary separation. Dental study casts were taken before operation and after removal of expansion device. And then, skeletal and dental parameters were measured pre- and post-operatively. Results: 1. Changes of mean interdental width 1) In group 1, mean maxillary interdental width was increased 70%($47{\sim}99%$), 95%($84{\sim}115%$), and 77%($57{\sim}94%$) of total expansion on canine, first premolar, and first molar region, respectively after retention. 2) In group 2, mean maxillary interdental width was increased 77%($59{\sim}100%$), 78%($45{\sim}107%$), and 86%($57{\sim}116%$) of total expansion on canine, first premolar, and first molar region, respectively after retention. 3) There was a statistical difference between the change of interdental width of group 1 and group 2 at first premolar(p<0.05). 2. Changes of mean interalveolar width 1) In group 1, mean maxillary alveolar bone width was increased 66%($42{\sim}84%$), 74%($42{\sim}104%$), and 57%($31{\sim}78%$) of total expansion on canine, first premolar, and first molar region, respectively after retention. 2) In Group 2, mean maxillary alveolar bone width was increased 73%($55{\sim}98%$), 67%($36{\sim}89%$), and 59%($48{\sim}73%$) of total expansion on canine, first premolar, and first molar region, respectively after retention. 3) There were no statistical differences between group 1 and group 2 at each teeth area. Conclusion: These results suggest that SARME without pterygomaxillary separation may allow the relatively equal expansion at both anterior and posterior teeth area and most amounts of maxillary interdental expansions were acquired with the expansion of the maxilla by SARME.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.5
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• pp.447-453
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• 2010

The hemifacial microsomia is characterized by variable underdevelopment of the craniofacial skeleton, external ear, and facial soft tissues. So, patients with hemifacial microsomia have an occlusal plane canting and malocclusion with facial asymmetry. Distraction osteogenesis (DO) with an intraoral or extraoral device is a technique using tension to generate new bone with gradual bone movement and remodeling. DO has especially been used to correct craniofacial deformities such as a hemifacial microsomia, facial asymmetry, and mandible defect that could not adequately be treated by conventional reconstruction with osteotomies. It has a significant advantage to lengthen soft and hard tissue of underdeveloped site without bone graft and a few complication such as nerve injury or muscle contracture. A 13-years old girl visited our clinic for the chief complaint of facial asymmetry. She had a left hypoplastic maxilla and mandible, occlusal plane canting and malocclusion. We diagnosed hemifacial microsomia and lanned DO to lengthen the affected side. Le Fort I osteotomy, left mandibular ramus and symphysis osteotomy were performed. The internal distraction devices fixed with screw on maxillary and mandibular ramus osteotomy sites. External devices were adapted to lower jaw for DO on symphysis osteotomy site and to upper jaw for rapid maxillary expansion (RME). At 7days after surgery, distraction was started at the rate of 1mm per day for 13days, and after 4months consolidation periods, distraction devices were removed. Simultaneous multiple maxillo-mandibular distraction osteogenesis with RME resulted in a satisfactory success in correcting facial asymmetry as well as occlusal plane canting for our hemifacial microsomia.