• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권2호
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• pp.184-199
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• 1996

The challenges to achieve three dimensional facial proportionality and occusal stability in many patients with complex dentofacial deformity have been met by the development and use of the maxilla, mandible, and chin surgery techniques in combination with efficient orthodontic treatment. There is a clinical, biological, and biomechanical foundation for simultaneous surgical repositioning of the maxilla, mandible, and chin in a significant proportion of adult and adolescent patients. A combination of the surgical and orthodontic approach may provide increased treatment efficiencies and optimal esthetic results. Art and science to determine the treatment objectives, specifically, the desired soft tissue changes are firstly established by using the clinician's "esthetic sense" of the facial beauty and proportion aided to a few cephalometric guidelines. In this sense, the dependence on the clinician's "esthetic eye" by Dr. Bell is more important in analyzing the facial proportion than the satisfaction of rigid cephalometric norms. The purpose of this article was to elucidate the indication for simultaneous surgical repositioning of the maxilla, mandible, and chin, and to describe the clinical cephalometric analysis for orthognathic surgery. Representative 6 case reports were presented and discussed to illustrate the esthetic, orthodontic, and surgical treatment objectives with long-term follow-up.

• Archives of Plastic Surgery
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• 제38권3호
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• pp.279-286
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• 2011

Purpose: Chin is located in a prominent position, and is important to balance and harmony of the face. Genioplasty is widely performed with patients' high satisfaction, yet being relatively simple procedure. Recently in analysis of dentofacial trait, three rotational variables of yaw, pith, and roll are considered with three translational variables (forward/backward, up/down, right/left). And we could correct chin deformity effectively by applying the three rotational variables with three translational variables in genioplasty. Methods: Twenty-eight patients who have chin deformity underwent osseous genioplasty. Preoperative photography, facial three dimensional computed tomography, and cephalography were taken while chin deformities were accessed. The chin deformity was classified into four categories; macrogenia, microgenia, asymmetric chin deformity, and combined chin deformity groups. According to the nature of chin deformities and the patients' desire, preoperative plans were formulated, in consideration of three rotational variables and translational variables. Through intraoral approach, anterior mandible was exposed in the subperiosteal plane between the mental foramens and beneath the mental foramens. In the anterior mandible, vertical and horizontal grid lines with 5 mm intervals were marked to confirm the spatial location of osteomized bone segment after osteotomy. Chin repositioning was done in consideration of axial rotation and planar translation. Results: Most of the patients had achieved satisfactory results with few complications. By considering the three rotational variables, it was possible to make the chin repositioning effectively. One of the patients complained about insufficient chin correction. In other case, persistent sensory impairment around chin was observed. Conclusion: In conclusion, it is worthwhile to apply preoperative analysis and operative procedures in consideration of a three rotational variables with three translational variables in genioplasty.

• Journal of Yeungnam Medical Science
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• 제15권2호
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• pp.316-324
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• 1998

This study was performed to evaluate the clinical features and treatment results on 55 temporomandibular disorder patients who had treated by conservative treatment using occlusal splint. The results were as follows; 1. The ratio of men to women was about 1:2.2 and most of the patients were second and third decades. 2. Pain was the most frequent symptom, followed by clicking and mouth opening limitation. 3. The number of acute and chronic groups on the basis of 6 months duration of symptoms were similar. 4. Most of patients had Angle's Class 1 molar relationships(78.2%), followed by Class 3 and Class 2. 5. Centric Relation splints were used alone for treatment of 34 patients and 21 patients were treated with Centric Relation splints and Anterior Repositioning splints. The treatment duration of the patients who had complained pain was average 9.8 weeks and 6 patients of them had slight pain continuously during follow-up. 6. Eleven patient's maximum mouth opening who had mouth opening limitation was improved from 30. 7mm to 43.0mm during procedures.

• 한국BIM학회 논문집
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• 제13권4호
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• pp.85-95
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• 2023

In the process of creating drawings based on Building Information Modeling (BIM), automatically generated annotations can cause interference issues depending on the drawing type. This study aims to develop an algorithm for repositioning annotations using genetic algorithms to minimize such interferences. To achieve this, the Application Programming Interface (API) of BIM software was used to analyze data extractable from BIM drawing files. The process involved defining drawing data related to annotation repositioning, preprocessing this data, and deriving optimal placement coordinates for the annotations. Furthermore, applying the developed algorithm to the preliminary design drawings of small and medium-sized neighborhood facilities resulted in approximately a 95.37% decrease in annotation interference, indicating that the proposed algorithm can significantly enhance productivity in BIM-based drawing tasks.

• 대한심미치과학회지
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• 제10권1호
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• pp.8-15
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• 2001

The Class III malocclusion classified in two types of Skeletal Class III and Pseudo Class III. In the case of the maxillary deficiency, the protraction H-G(facemask) with Bonded RPE can be used. For children with A-P and vertical maxillary deficiency, the preferred treatment is to move the maxilla into a more anterior and inferior position, which also increases its size as bone is added at the posterior and superior sutures. Successful forward repositioning of the maxilla can be accomplished before age 8. To resist tooth movement as much as possible, the maxillary teeth should be splinted together as a single unit. The maxillary appliance must have hooks for attachment to the facemask that are located in the canine-primary molar area above the occlusal plane. The facemask usually worn until a positive overjet of 2-5mm is achieved interincisally. Occipital chin cup is successful in those patients who can bring their incisors close to an edge-to-edge position when in centric relation. This treatment is particularly useful in patients who begin treatment with a short lower anterior facial height, as this type of treatment can lead to an increase in lower anterior facial height. If the pull of the chin cup is directed below the condyle, the force of the appliance may lead to a downward and backward rotation of the mandible.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.30.1-30.6
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• 2018

Background: The purpose of the present study was to investigate the differences in the position and shape of the anterior loop of the inferior alveolar nerve (ALIAN) in relation to the growth pattern of the mandibular functional subunit. Methods: The study was conducted on 56 patients among those who had undergone orthognathic surgery at the Gangnam Severance Hospital between January 2010 and December 2015. Preoperative computerized tomography (CT) images were analyzed using the Simplant OMS software (ver.14.0 Materialise Medical, Leuven, Belgium). The anterior and inferior lengths of ALIAN (dAnt and dInf) and each length of the mandibular functional subunits were measured. The relationship between dAnt, dInf, and the growth pattern of the mandibular subunits was analyzed. Results: The length of the anterior portion of ALIAN (dAnt) reached 3.34 ± 1.59 mm in prognathism and 1.00 ± 0.97 mm in retrognathism. The length of the inferior portion of ALIAN (dInf) reached 6.81 ± 1.33 mm in prognathism and 5.56 ± 1.34 mm in retrognathism. The analysis of Pearson's correlation coefficiency on all samples showed that the lengths of functional subunits were positively correlated with the loop depth. The length of the symphysis area in prognathic patients was positively correlated with the anterior loop depth (p = 0.005). Conclusions: Both the anterior and inferior length of ALIAN are longer in prognathic patients. Especially, it seems to be associated with the growth of the symphysis area.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권2호
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• pp.48-54
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• 1990

This is a report of 4 cases of the surgical correction of mandibular prognathism with chief complaint of mastication difficulty, facial asymmetry and protrusive chin. We performed sagittal spit ramus osteotomy for the prognathism, we used the repositioning plate for conserving the condylar segment into its original position and fixed the osteotomized bone segments rigidly with adjustable monocortical plate. Intermaxillary fixation was performed during 2 weeks. As a results, we found the following advantage. 1. Rigid fixation effect like the fixation by the tandem screw. 2. Decreased postoprative swelling. 3. It is needless to do the stab incision for the transbuccal set instrument. 4. It is more convenient to perform the rigid fixation in the monocortical plate method than screw technique.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권3호
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• pp.107-113
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• 2023

Bimaxillary transverse width discrepancies are commonly encountered among patients with dentofacial deformities. Skeletal discrepancies should be diagnosed and managed appropriately with possible surgical corrections. Transverse width deficiencies can present in varieties of combinations involving the maxilla and mandible. We observed that in a significant proportion of cases, the maxilla is normal, and the mandible showed deficiency in the transverse dimension after pre-surgical orthodontics. We designed novel osteotomy techniques to enhance mandibular transverse width correction, as well as simultaneous genioplasty. Chin repositioning along any plane is applicable concomitant with mandibular midline arch widening. When there is a requirement for larger widening, gonial angle reduction may be necessary. This technical note focuses on key points in management of patients with transversely deficient mandible and the factors affecting the outcome and stability. Further research on the maximum amount of stable widening will be conducted. We believe that developing evidence-based additional modifications to existing conventional surgical procedures can aid precise correction of complex dentofacial deformities.

• 대한치과교정학회지
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• 제39권6호
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• pp.362-371
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• 2009

본 연구는 상악전방견인장치 또는 이모장치 치료 후 고정식 교정장치로 치료 받은 III급 부정교합 환자의 치료효과에 대한 종단적 비교를 위해 시행되었다. 상악전방견인 치료 또는 이모장치 치료 전의 골격 및 치아 유형이 유사하며 고정식 교정치료 후 좋은 유지결과(I급 구치/견치 관계 및 양의 수직/수평피개)를 보이는 21명의 환자(1군, 상악전방견인장치, 11명; 2군, 이모장치, 10명)를 대상으로 하였다. 상악전방견인 치료 또는 이모장치 치료 전(T0)과 후(T1), 고정식 교정치료 후 유지기간(T2)에 측모두부방사선사진을 촬영하여 골격 및 치아에 대한 계측치를 이용하였다. 통계적 분석을 위해 비모수 검정법(Mann-Whitney U-test and Wilcoxon signed-rank test)을 이용하였다. 악정형 치료 시기(T0-T1)에, 1군에서는 상악골의 전방 이동 (point A, p < 0.05), 상악 전치의 순측경사 (p < 0.01) 및 수평피개의 증가 (p < 0.01)가 보였다. 하악골은 1군과 2군 모두에서 후방 위치를 보였다 (SNB, Pog-N perp, ANB, p < 0.01). 1군에서는 수직고경의 증가 (SN-GoGn, ANS-Me/N-Me, Bjork sum, p < 0.01)가 나타난 반면에, 2군에서는 articular angle의 증가 (p < 0.05)와 gonial angle의 감소 (p < 0.01)가 보였다. 고정식 교정치료 및 유지기간(T1-T2)에, 1군과 2군 모두는 상악골의 전방성장 (point A, p < 0.05)을 보였다. 한편 1군은 하악골의 전방성장 (Pog-N perp, p < 0.01) 및 반시계방향 회전 (SN- GoGn, Bjork sum, p < 0.05)과 하악 전치의 순측경사 (IMPA, p < 0.05)를 나타냈으며, 2군은 ANS-Me/N-Me의 증가 (p < 0.01)와 수직피개의 감소 (p < 0.05)를 보였다. 비록 상악전방견인 치료와 이모장치 치료의 골격 및 치성적 효과가 서로 차이가 있을지라도, 이 두 치료법으로 인한 결과가 장기간 안정적으로 유지되기 위해서 하악골의 회전 및 성장에 맞추어 상악골의 지속적인 전방성장이 필요한 것으로 생각된다.