• 대한치과교정학회지
• /
• 제50권5호
• /
• pp.293-303
• /
• 2020

Objective: To investigate the three-dimensional (3D) surgical accuracy between virtually planned and actual surgical movements (SM) of the maxilla in two-jaw orthognathic surgery. Methods: The sample consisted of 15 skeletal Class III patients who underwent two-jaw orthognathic surgery performed by a single surgeon using a virtual surgical simulation (VSS) software. The 3D cone-beam computed tomography (CBCT) images were obtained before (T0) and after surgery (T1). After merging the dental cast image onto the T0 CBCT image, VSS was performed. SM were classified into midline correction (anterior and posterior), advancement, setback, anterior elongation, and impaction (total and posterior). The landmarks were the midpoint between the central incisors, the mesiobuccal cusp tip (MBCT) of both first molars, and the midpoint of the two MBCTs. The amount and direction of SM by VSS and actual surgery were measured using 3D coordinates of the landmarks. Discrepancies less than 1 mm between VSS and T1 landmarks indicated a precise outcome. The surgical achievement percentage (SAP, [amount of movement in actual surgery/amount of movement in VSS] × 100) (%) and precision percentage (PP, [number of patients with precise outcome/number of total patients] × 100) (%) were compared among SM types using Fisher's exact and Kruskal-Wallis tests. Results: Overall mean discrepancy between VSS and actual surgery, SAP, and PP were 0.13 mm, 89.9%, and 68.3%, respectively. There was no significant difference in the SAP and PP values among the seven SM types (all p > 0.05). Conclusions: VSS could be considered as an effective tool for increasing surgical accuracy.

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

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제48권4호
• /
• pp.201-206
• /
• 2022

Objectives: Contemporary biometric technologies have been gaining traction in both public and private security sectors. Facial recognition is the most commonly used biometric technology for this purpose. We aimed to evaluate the ability of a publicly available facial recognition application program interface to calculate similarity scores of presurgical and postsurgical photographs of patients who had orthognathic surgery. Materials and Methods: Presurgical and postsurgical photographs of 75 patients who had orthognathic surgery between January 2018 and November 2020 in our department were used. Frontal photographs of patients in relaxed and smiling states were taken. The patients were classified into three groups: Group 2 had one-jaw surgery, Group 3 had two-jaw surgery to correct mandibular prognathism, and Group 4 had two-jaw surgery to correct facial asymmetry. For comparison, photographs of 10 participants were used as controls (Group 1). Two facial recognition application programs (Face X and Azure) were used to assess similarity scores. Results: The similarity scores in the two programs showed significant results. The similarity score of the control group, which did not undergo orthognathic surgery, was the highest. The results for Group 2, Group 3, and Group 4 were higher in the order of Group 2, Group 3, and Group 4. Conclusion: In this study, all orthodontic patients were recognized as the same person using the face recognition program before and after surgery. A significant difference in similarity results was obtained between the groups with both Face X and Azure and in both relaxed and smiling states.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제26권4호
• /
• pp.407-413
• /
• 2000

To evaluate the stability after orthognathic surgery in cleft lip and palate patients using rigid fixation, 20 patients underwent primary repair in childhood and later developed a jaw deformity and malocclusion that required orthognathic surgery were reviewed. Two groups, one of 10 patients performed Le Fort I osteotomy with sagittal split ramus osteotomy and one of 10 patients with sagittal split ramus osteotomy of the mandible, were evaluated. Each group had unilateral cleft only and all alveolar cleft sites had been grafted with autogeneous bone before the orthognathic surgery. The amount of surgical movement and relapse were compared in both horizontal and vertical dimensions. Two-jaw surgery group was more stable than mandibular surgery only group in mandibular position (p< 0.05). Statistically significant relapse was observed in mandibular skeletal point in mandibular surgery group (p<0.05). There was no statistically significant relapse in the skeletal point of two-jaw surgery group. However, the correlation between the horizontal surgical movement and relapse was detected (r = 0.88). This correlation indicates the need of overcorrection. The presence of scar tissues and relatively deficient maxillary bone could be attributed to this close relation between the surgical change and relapse.

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

• 대한치과교정학회지
• /
• 제25권5호
• /
• pp.613-625
• /
• 1995

본 연구는 골격성 III급 부정교합 환자에서 술전 상태와 수술방법 사이의 관계 및 악교정 수술후 재발경향을 조사하기 위하여 시행하였다. 연구 대상으로는 악교정수술을 받은 31명(남자 17명, 여자 14명)을 선택하였고, 이중 20명은 편악수술, 11명은 양악수술을 시행하였으며, 평균연령은 22.5세였다. 각 대상에서 술전, 수술직후, 1년 이상 경과 후의 측모두부방사선 규격사진을 채득하여, 투사도를 작성하고, 분석하여 다음과 같은 결과를 얻었다. 1. 하악만을 수술한 군보다 양악 동시수술군에서 하악체의 길이가 4.24mm, 하안모 고경의 길이가4.64mn, 하순의 길이가 4.13mm 더 길게 나타났으며, 반면 수평피개도는 3.13mm 더 작게 나타났다. 2. 하악만을 수술한 군에서 $8.95\pm4.45mm$ 하악이 후방이동되었으며, 양악 동시수술군에서 상악은 $5.15\pm3.46mm$ 전방이동되었고, 하악은 $7.24\pm9.11mm$ 후방이동되었다. 3. 최소 1년 이상 경과 후와 수술직후의 변화에 있어서 양악 동시수술군에서 A point는 $1.02\pm2.14mm$, Pn에서는 $1.05\pm1.48mm$, Sn에서는 $1.55\pm1.37mm$ 후방이동되었다. 4. 최소 1년 이상 경과 후와 수술직후의 변화에 있어서 B point에서 하악만을 수술한 군은 $28\%$ 양악 동시수술군은 $8\%$, B' point에서 하악만을 수술한 군은 $24\%$, 양악 동시수술군은 $3\%$ 전방이동되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제34권6호
• /
• pp.628-634
• /
• 2008

The purpose of this study is to examine reproducibility of operation plan and 3-dimentional jaw movement patterns by comparing jaw position of STO with post-operative jaw position. Twenty patients with class III dental and skeletal malocclusion who were treated with Le-Fort I osteotomy and B-SSRO were reviewed. Lateral cephalometric radiographs were taken within two weeks before operation and two days after operation. Cephalometric radiographs were compared and analyzed with orthognathic computer program '$V-Ceph^{TM}$'. Post-operative maxillary advancement was insufficient compared to maxillary advancement through STO. Post-operative setback movement was over compared to mandibular setback movement through STO. But statistically this is not significant. Maxillary vertical location is insignificant on the whole. Especially post-operative maxillary clockwise rotation is significant compared to maxillary rotation through STO. Post-operative maxillary clockwise rotation tendency is generally observed in all patients. So surgeons and staffs must consider this tendency when operation plan is established ans operation is being performed. Using intra or extra oral marking points, face bow, and bite plate will make exact surgery possible.

• 대한치과의사협회지
• /
• 제57권2호
• /
• pp.100-104
• /
• 2019

Orthognathic surgery is designed to correct problems of the jaw and face and restore facial harmony. The limitations of orthognathic surgery occur at all steps of the surgical workflow: preoperative planning, simulation, and operation. Many studies have shown the accuracy and advantages of 3 dimensional computer-assisted program for orthognathic surgery. The purpose of this paper is to introduce the accuracy of the maxillary repositioning in patients who underwent orthognathic surgery using a 3 dimensional computer assisted surgery program. The reliability of computer guided orthognathic surgery using splint and surgical guide need to be improved further. The 3 dimensional computer assisted analysis seems to be more precise to interpret than two-dimensional analysis. High-precision planning of orthognathic surgery has predictable results. Three-dimensional computer assisted orthognathic surgery has the following advantages : planned surgical movement is possible, splints guide with CAD/CAM technology; and increase predictable results .Computer assisted simulation surgery ensures accuracy during surgery, thereby facilitating predictable results. It may provide solution that enables surgeon to perform planned surgery more accurately.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제20권4호
• /
• pp.300-304
• /
• 1998

Moderns have desire likely to be further good-looking concomitant with a qualitative advancement of the life. With one of this phenomenon, an orthognathic surgery performing at the dept. of oral and maxillofacial surgery have been becoming a more extensively. It's possible to occur many complications during the operations and especially, an excessive bleeding of those may be fatal and so a transfusion is performing for the prevention &management of that. But, because of the rate of increase of an blood-born infection like AIDS via transfusion, nowadays an autologous blood transfusion is interesting to us. We made a comparative study of an amount of blood loss &transfusion using hemoglobin value after classifying the orthognathic surgeries from Feb. '97 to Mar. '98 in single-jaw and doublejaw surgery. And we intended to set a standard against of a routine preoperative cross-matching deciding the amount of predictive homologous blood transfusion according to operative method. Simultaneously, we studied the realization &effectiveness of autologous blood transfusion with some cases, so would like to present. Results: 1. Single-jaw operation can be performed without blood transfusion or with homologous blood transfusion through only blood typing & screening. 2. We commonly transfuse two units of blood with double-jaw operation and an autologous blood transfusion has much more advantage than an homologous blood transfusion. 3. We can reduce charge associated with blood transfusion through precisely preoperative evaluation of patients and proper type of blood transfusion.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제17권1호
• /
• pp.1-9
• /
• 1995

1986년 1월부터 1993년 12월까지 8년간 외과적 교정술을 시행한 117 증례에대하여 임상적인 관찰을 시행하였다. 1) 남녀 성비는 1:1.4로 여자가 많았으며 평균연령은 23.0세였다. 2) 악교정수술을 받기위하여 내원한 환자의 진단에 따른 분류를 보면 하악 전들증의 경우가 87증례(75.0%)로 주종을 이루고 있었다. 3) 수술방법중 하악단독수술은 88증례, 상악골 단독수술은 6증례, 상하악 동시이동술은 23증례였으며 이중 하악지 시상골절단술이 사용된 경우가 84증례(71.8%)로 가장 많았다. 4) 골편의 고정을 위하여 강선고정보다 Miniplate나 Screw 를 이용한 고정이 점차 선호되고 있으며 전체수술에서 견고고정의 비율은 66.0%였다. 5) 본 교실에서는 외가적 교정수술 환자를 대상으로 1992년 2월부터 저혈식 자가수혈을 이용하고 있으며 One Jaw surgery 에서는 2 pints, Two Jaw surgery 에서는 3 pints를 준비하고 잇다. 6) 악교정수술의 합병증으로는 하순지각마비등의 신경손상이 전체수술의 63증례(53.8%)로 가장 많았으며 골편의 잘못된 위치, 과두위치보존의 실패, 견고고정의 불안정등이 원인이 되어 5증례에서 재수술을 시행하였다.