• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권2호
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• pp.124-129
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• 2013

Multiple segment osteotomy orthognathic surgery serves to combine the total or segmental maxillary and mandibular correction of the dentofacial deformities with concurrent procedures to provide immediate repositioning to the dento-osseous elements. In addition, splitting the palate may often be necessary to correct a functionally poor relationship of the maxilla to the mandible or the facial skeleton by realigning the maxillary arch. In this case, the discrepancy in a bimaxillary horizontal relationship and the space between the 2nd premolar and 2nd molar was retained after lengthy preoperative orthodontic treatment. However, we could correct these dento-osseous discrepancies immediately by performing midpalatal expansion, anterior segmental osteotomy and symphyseal osteotomy with bimaxillary osteotomies. If the blood supply to each segment segments was maintained and primary closure of the operation site was feasible, multiple segment osteotomy was considered as a very effective technique for treating dentofacial deformities in vertical, transverse, and sagittal dimensions with differential repositioning of all segments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권2호
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• pp.129-137
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• 2006

The treatment plan for orthognathic surgery must be based on accurate predictions, and this can be produced the most esthetic, functional and stable results. The purpose of this study was aimed to evaluate the amount and interrelationship of the gonial angle and the mandibular width change after the mandibular setback surgery in the mandibular prognathic patients. Twenty patients were selected who received orthognathic surgery after presurgical orthodontic treatment. The patients with skeletal and dental Class III malocclusion were operated upon with bilateral sagittal split ramus osteotomy and mandibular setback. The lateral and posteroanterior cephalometric radiographs were taken preoperatively, postoperative 1 day and 12 months later after the orthognathic surgery, and then the gonial angle and mandibular width were measured. The computerized statistical analysis was carried out with SPSS/PC program. The gonial angle at postoperative 1 day was decreased about $5.3^{\circ}$ than preoperative value and the gonial angle at postoperative 12 months was increased about $1.4^{\circ}$ than postoperative 1 day. So the gonial angle at postoperative 12 months was decreased about $3.9^{\circ}$ than preoperative value. The mean preoperative gonial angle was $125.35^{\circ}{\pm}7.36$, showing significantly high value than normal and mean gonial angle at postoperative 12 months was $121.45^{\circ}{\pm}6.81$, showing value near to normal. The mandibular width at postoperative 1 day was decreased about 1.1 mm than preoperative value and the mandibular width at postoperative 12 months was more decreased about 1.7 mm than postoperative 1 day. So the mandibular width at postoperative 12 months was decreased about 2.8 mm than preoperative value. These results indicate that sagittal split ramus osteotomy in mandibular prognathic patients with high gonial angle is effective to improvement of gonial angle. It is considered to be helpful for maintenance of postoperative stable gonial angle area that detailed postoperative care and follow-up.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권6호
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• pp.407-420
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• 2003

Purpose : The purpose of this study was to analyse the facial changes and factors contributing to then after bilateral sagittal split ramus osteotomy of mandibular prognathism. Materials and Methods : Forty patients with Class III dental and skeletal malocclusion who were treated with bilateral sagittal split ramus osteotomy were reviewed. Frontal and lateral cephalometric radiographs were taken preoperatively, immediate postoperatively and more than six months postoperatively in each patient. After tracing the cephalometric radiographs, various parameters were measured. Results : 1. Gonial angle at postoperative two days was decreased about $10.4^{\circ}$ than preoperatively and gonial angle at postoperative six months was increased about $6.8^{\circ}$ than postoperative two days. So, gonial angle at postoperative six months was decreased about $3.6^{\circ}$ than preoperative gonial angle. 2. Facial height postoperative two days was decreased about 0.8mm than preoperatively and facial height at postoperative six months was decreased about 0.7mm than postoperative two days. So, facial height at postoperative six months was decreased about 1.5mm than preoperative facial height. 3. Mandibular width postoperative two days was decreased about 1.0mm than preoperatively and mandibular width at postoperative six months was increased about 1.8mm than postoperative two days. So, mandibular width at postoperative six months was decreased about 2.8mm than preoperative mandibular width. 4. Amount of set back and mandibular plane angle were not influencing on relapse degree. Conclusion : It is thought that bilateral sagittal split ramus osteotomy in mandibular prognathic patients is effective to improve long face and steep gonial angle. More prudent operation and careful postoperative management is required to maintain stable face postoperatively. Further research for soft tissue changes and factors which are related with relapse is needed.

• 대한치과교정학회지
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• 제50권3호
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• pp.206-215
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• 2020

Osteochondroma is a common benign tumor of bones, but it is rare in the mandibular condyle. With its outgrowth it manifests clinically as deviation of the mandible limitation of mouth opening, and facial asymmetry. After the tumor is diagnosed on the basis of clinical symptoms and radiographic examination including cone-beam computed tomography (CBCT) analysis, an appropriate surgery and treatment plan should be formulated. Herein, we present the case of a 44-year-old female patient who visited our dental hospital because her chin point had been deviating to the left side slowly but progressively over the last 3 years and she had difficulty masticating. Based on CBCT, she was diagnosed with skeletal Class III malocclusion accompanied by osteochondroma of the right mandibular condyle. Maxillary occlusal cant with the right side down was observed, but it was confirmed to be an extrusion of the molars associated with dental compensation. Therefore, after intrusion of the right molars with the use of temporary anchorage devices, sagittal split ramus osteotomy was used to remove the tumor and perform orthognathic surgery simultaneously. During 6 months after the surgery, continuous bone resorption and remodeling were observed in the condyle of the affected side, which led to a change in occlusion. During the postoperative orthodontic treatment, intrusive force and buccal torque were applied to the molars on the affected side, and a proper buccal overjet was created. After 18 months, CBCT revealed that the rate of bone absorption was continuously reduced, bone corticalization appeared, and good occlusion and a satisfying facial profile were achieved.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권3호
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• pp.255-259
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• 2005

We observed 469 cases (male 217 cases, female 252 cases) with dento-facial deformity for 10 years from Jan 1994 to Dec 2003. The ratio of male to female was 1:1.2 and the mean age was 23.3 years (male 24.0 years, female 22.6 years) ranged from 11 to 43 years. The most dominant group was related to mandibular prognathism (80.4%). A rate of 83.8% demonstrated mandibular protrusion according to Slavicek's classification (n=160), and 85.4% were classified as skeletal Class III type according to Sugawara's classification (n=151). Surgical method were divided into 355 cases of one jaw surgery (single method), 26 cases of one jaw surgery (combined method), and 77 cases of two jaw surgery. Sagittal split osteotomy were performed on 316 cases (69.0%). The average operation time and blood loss in SSRO were $4.1{\pm}2.2$ hrs. and $138.8{\pm}222.6$ ml (n=152).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권2호
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• pp.160-163
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• 2005

This study was designed to assess skeletal stabilily after surgical correction of mandibular prognathism by bilateral saggital split ramus osteotomy(BSSRO) and fixation with absorbable screws. From July 2001 to September 2003, 30 patients with Class III malocclusion were treated with BSSRO and mandibular setback. They underwent fixation with Biosorb$^{TM}$ FX screws. Cephalograms were obtained preoperatibely, 2 or 3 days postoperatively, and about 12 months after the operation. Changes in the position of lower incisor tip, B point, and pogonion were examined on lateral cephalograms. The mean mandibular setback just after surgery was 10.6mm. 12 months after surgery, mean relapse at pogonion represented 17.9% and 15.1% at B point. Our results suggest that fixation of the bony segments with absorbable screws after BSSO may be used effectively in properly selected cases.

• 대한치과교정학회지
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• 제43권1호
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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.

• 대한치과교정학회지
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• 제49권4호
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• pp.222-234
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• 2019

Objective: To investigate the three-dimensional lip vermilion changes after extraction and non-extraction orthodontic treatment in female adult patients and explore the correlation between lip vermilion changes and incisor changes. Methods: Forty-seven young female adult patients were enrolled in this study (skeletal Class III patients were excluded), including 34 lip-protruding patients treated by extraction of four first premolars (18 patients requiring mini-implants for maximum anchorage control and 16 patients without mini-implants) and 13 patients requiring non-extraction treatment. Nine angles, seven distances, and the surface area of the lip vermilion were measured by using pre- and post-treatment three-dimensional facial scans. Linear and angular measurements of incisors were performed on lateral cephalograms. Results: There were no significant changes in the vermilion measurements in the non-extraction group. The vermilion angle, vermilion height, central bow angle, height/width ratio, and vermilion surface area decreased significantly after the orthodontic treatment in the extraction groups, but the upper/lower vermilion proportion remained unchanged. Significant correlations were found between the changes in incisor position and those in vermilion angles, vermilion height, and surface area. Conclusions: Extraction of the four first premolars probably produced an aesthetic improvement in lip vermilion morphology. However, the upper/lower vermilion proportion remained unchanged. The variations in the vermilion were closely related to incisor changes, especially the upper incisor inclination changes.

• Archives of Plastic Surgery
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• 제48권1호
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• pp.61-68
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• 2021

Background This study evaluated changes in nasal airway function following Le Fort I osteotomy with maxillary impaction according to the Nasal Obstruction Symptom Evaluation (NOSE) scale. Methods This cohort study included 13 patients who underwent Le Fort I osteotomy with maxillary impaction. Nasal airway function was evaluated based on the NOSE scale preoperatively and at 3 months postoperatively. The change in the NOSE score was calculated as the preoperative score minus the postoperative score. If the normality assumptions for changes in the NOSE score were not met, a nonparametric test (the Wilcoxon signed-rank test) was used. Differences in NOSE score changes according to patient characteristics and surgical factors were evaluated using the Kruskal-Wallis test and the Mann-Whitney test. Results Patients ranged in age from 18 to 29 years (mean ±standard deviation [SD], 23.00±3.87 years). Three were men and 10 were women. Eleven patients (84%) had an acquired dentofacial deformity with skeletal class III malocclusion. The preoperative NOSE scores ranged from 40 to 90 (mean±SD, 68.92±16.68), and the postoperative NOSE scores ranged from 25 to 80 (53.84±18.83). The cohort as a whole showed significant improvement in nasal airway function following maxillary impaction (P=0.028). Eleven patients (84%) had either improved (n=8) or unchanged (n=3) postoperative NOSE scores. However, nasal airway function deteriorated in two patients. Patient characteristics and surgical factors were not correlated with preoperative or postoperative NOSE scores. Conclusions Nasal airway function as evaluated using the NOSE scale improved after maxillary impaction.

• 대한치과교정학회지
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• 제51권1호
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• pp.43-54
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• 2021

Objective: To investigate the cephalometric predictors of the future need for orthognathic surgery in Korean patients with unilateral cleft lip and palate (UCLP) despite long-term use of facemask with miniplate (FMMP). Methods: The sample consisted of 53 UCLP patients treated by a single orthodontist using an identical protocol. Lateral cephalograms were taken before commencement of FMMP therapy (T0; mean age, 10.45 years), after FMMP therapy (T1; mean age, 14.72 years), and at follow-up (T2; mean age, 18.68 years). Twenty-eight cephalometric variables were measured. At T2 stage, the subjects were divided into FMMP-Nonsurgery (n = 33, 62.3%) and FMMP-Surgery (n = 20, 37.7%) groups according to cephalometric criteria (point A-nasion-point B [ANB] < -3°; Wits-appraisal < -5 mm; and Harvold unit difference [HUD] > 34 mm for FMMP-Surgery group). Statistical analyses including discrimination analysis were performed. Results: In FMMP-Surgery group, the forward position of the mandible at T0 stage was maintained throughout the whole stages and Class III relationship worsened with significant growth of the mandibular body and ramus and counterclockwise rotation of the maxilla and mandible at the T1 and T2 stages. Six cephalometric variables at T0 stage including ANB, anteroposterior dysplasia indicator, Wits-appraisal, mandibular body length, HUD, and overjet were selected as effective predictors of the future need for surgical intervention to correct sagittal skeletal discrepancies. Conclusions: Despite long-term use of FMMP therapy, 37.7% of UCLP patients became candidates for orthognathic surgery. Therefore, differential diagnosis is necessary to predict the future need for orthognathic surgery at early age.