• 대한치과교정학회지
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• 제50권5호
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• pp.346-355
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• 2020

The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized mini-plates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400-500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

• Archives of Plastic Surgery
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• 제32권5호
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• pp.547-554
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• 2005

Orthognathic surgery for Class III malocclusion requires an elaborate preoperative planning using cephalometries or Mock surgery models which enable the surgeon to anticipate postoperative skeletal changes of maxilla and mandible as well as dentition. After surgery, patient's satisfaction is greatly influenced by appearance of soft tissue change. Therefore, it is imperative to predict a relatively accurate soft tissue change prior to surgery. A 5 year retrospective study was designed to evaluate the soft tissue change after sagittal split osteotomy of ramus(SSRO) for class III malocclusion. Analyses of preoperative and postoperative anthropometric measurements were performed. Patients who were treated only by SSRO for class III malocclusion and could follow up for 6 months were studied. Among them, the patients who had history of cleft palate and lip or hemifacial microsomia were excluded. Soft tissue changes were estimated by using the frontal and lateral photographs. Skeletal changes were observed by measuring amount of set back and angular changes of mandible to the reference line by using cephalometries. Relapses were also measured 6 months after the operation. We could observe skeletal changes were more profound than soft tissue changes concerning amount of set back, but soft tissue changes were also profound in angle. Relapse was more profound in skeleton than soft tissue but the amount was not significant. In spite of the variables which may affect proper assessment of the soft tissue change after skeletal relocation, this study can serve as a guide for exact prediction of the postoperative change of soft tissue and skeleton.

• 대한치과교정학회지
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• 제23권3호
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• pp.341-358
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• 1993

This study was investigated to evaluate the morphologic characteristics of deepbite tendency as multiple factors. The subjects consisted of 60 control subjects(male 25, female 35) and 137 deephite patients(68 male, 69 female). The deepbite group was composed of 4 subgroups(Class I 44, Class II div. 1 40, Class II div. 2 13, Class III 40). The mean age was 21.57 year for the control group 21 year for deepbite group lateral cephalograph in centric occlusion were taken, traced, and digitized for each subject. The statistically computerized analysis was carried out with SAS program. The results were as follows ; 1. In deepbite group, saddle angle is lesser than that of normal group. 2. The vertical dysplasia is prominent on anterior lower face and is closely related with mandibular form and inclination. 3. Without consideration of sagittal relationship, the dental factors such as curve of Spee, interincisal angle, U1 to upper lip length were prominent in the deepbite group. 4. Although there were individual variances in the perioral soft tissue profile, the lip presented more protruded pattern. 5. There was no significant difference in hyoid bone position and inclination between normal and deepbite group. 6. The multivariate discriminant analysis between normal and Class I deepbite group showed that curve of Spee, AB-MP angle, interincisal angle, articular agnle were critical in the determination of deepbite as multiple factors.

• 대한치과교정학회지
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• 제44권6호
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• pp.330-341
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• 2014

A 19-year-old woman presented to our dental clinic with anterior crossbite and mandibular prognathism. She had a concave profile, long face, and Angle Class III molar relationship. She showed disharmony in the crowding of the maxillomandibular dentition and midline deviation. The diagnosis and treatment plan were established by a three-dimensional (3D) virtual setup and 3D surgical simulation, and a surgical wafer was produced using the stereolithography technique. No presurgical orthodontic treatment was performed. Using the surgery-first approach, Le Fort I maxillary osteotomy and mandibular bilateral intraoral vertical ramus osteotomy setback were carried out. Treatment was completed with postorthodontic treatment. Thus, symmetrical and balanced facial soft tissue and facial form as well as stabilized and well-balanced occlusion were achieved.

• Journal of Yeungnam Medical Science
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• 제21권2호
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• pp.242-250
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• 2004

In general, the skeletal class III has the characteristics of mandibular overgrowth with a normal maxillary growth or maxillary undergrowth with a normal mandibular growth And clinical and radiographic evaluations of the patient are needed. However, the treatment plan is not dependent on these evaluations alone, because patient's general condition and hope for aesthetics varies. The aim of this report is to consider the treatment of a medically compromised patient with an anterior open bite and skeletal class III, which showed a severe mandibular overgrowth. In 2003, a 17-year-old boy with epilepsy, mental retardation presented at our clinic complaining of concave profile. A clinical examination showed severe mandibular prognathism with an anterior open bite. The radiographic examination revealed a short cranial base, a moderate maxillary overgrowth, severe mandibular overgrowth and skeletal open bite tendency. In 2004, he was verified to have no potential of growth by hand-and-wrist radiographs and an endocrine examination. He completed the preoperative orthodontic treatment and orthognathic surgery (sagittal split ramus osteotomy, genioplasty). He was evaluated on the first visit, the preoperative period and the postoperative period with a clinical and radiographic examination. At the first visit, the patient showed moderate overgrowth of the maxilla, severe overgrowth of the mandible, and a subsequential skeletal open bite. After the preoperative orthodontic treatment (preoperative period), the patient showed the same skeletal problem as before and a decompensated dentition for orthognathic surgery. After orthognathic surgery, his profile had improved, but he had still a skeletal openbite tendency because the maxillary orthognathic surgery was not performed. Severe mandibular prognathism with a maxillary overgrowth and anterior open bite should be treated by bimaxillary orthognathic surgery. However, one-jaw orthognathic surgery on the remaining the skeletal open bite tendency was performed for his medical problem and facial esthetics. This subsequential open bite should be resolved with a postoperative orthodontic treatment.

• 대한치과교정학회지
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• 제23권4호
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• pp.475-483
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• 1993

The purpose of this study was to investigate the treatment effects on anterior crossbite patients using chin cap and labiolingual arch appliance. In the present study, I statistically evaluated measurement values on a cephalogram before and after treatment form twenty anterior crossbite cases. The results were as follows: 1. In the craniofacial patterns, cranial base increased after treatment. 2. In the maxillo-mandibular relationship, ANB and Facial convexity significantly increased. 3. In the denture patterns, occlusal plane, Ul to FH and Overjet significantly increased. On the contrary overbite decreased significantly. Lower incisors inclined lingually. 4. In the soft tissue profile changes, lower lip protrusion was signifacantly improved.

• 대한치과교정학회지
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• 제15권2호
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• pp.369-376
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• 1985

A 10 year & 11 month old girl patient who had Angle's Class III malocclusion were treated by chin cap and fixed appliances. The treatment results obtained were as to]lows: 1. The anterior crossbite was corrected. 2. The functional overbite & overjet were established. 3. The favorable molar relationships were achieved. 4. The forward growth of the mandible was restrained. 5. The axial inclination of the upper & lower incisors were changed and the upper dental arch length was increased. 6. The facial profile was improved resulting from the good upper & lower jaw relations. 7. There was no harmful changes on the teeth S the periodontal tissues after treatment. 8. The good occlusal stability was showed after 1 year of retention.

• 대한치과의사협회지
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• 제23권7호통권194호
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• pp.625-630
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• 1985

11 years 7 months old female had a reverse object of anterior teeth and class III molar relationship. Maxillary right and left canines were erupted labially and lower left lateral incisor was congenitally missed. She was treated by rapid palatal expansion and full band technique with extraction of maxillary and mandibular second molars. The following results were obtained. 1. Maxilary arch was expanded. 2. Anterior cross-bite and crowding was corrected. 3. Molar relationship was corrected. 4. Profile was somewhat improved.

• 대한치과교정학회지
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• 제36권1호
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• pp.63-73
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• 2006

악교정 수술 시행 시 연조직 변화에 대한 대부분의 연구는 II급 부정교합을 대상으로 하였다. 또한 수술 방법에 따른 연조직 변화에 대한 비교 연구가 부족하였다. 따라서 이 연구는 골격성 III급 부정교합자에서 상악골 전진술과 하악골 후퇴술을 동시에 시행한 양악 수술과 하악골 편악 수술 시행 시, 경조직과 연조직 측모 및 연조직 두께의 변화를 관찰하고, 수술 전후 변화의 상관성을 산출하며, 경조직 변화에 수반하는 연조직 변화의 비율을 산출하여 교정-악교정 수술 복합 치료 계획 수립과 결과의 예측에 이용하고자 시행되었다. 경희대학교 치과병원 교정과에 내원하여 골격성 III급 부정교합자로 진단받은 환자 52명을 대상으로 하여, Le Fort I osteotomy를 이용한 상악골 전방이동술과 시상분할골절단술을 이용한 하악골 후퇴술을 시행한 양악 수술군 26명과 하악골 후퇴술만을 시행한 편악 수술군 26명으로 구분하여, 수술 전후 측모두부방사선규격사진을 계측, 분석하여 다음과 같은 결과를 얻었다. 양악 수술군은 골격 변화량의 72.4% 비율로 상순 부위 연조직의 전방 이동을 보였으며, 편악 수술군은 통계적으로 유의한 변화를 보이지 않았다. 비순각은 양악 수술군에서 편악 수술군에 비해 더 크게 증가하였다. 이순각은 편악 수술군에서 더 크게 감소하였다. 하악골의 후방 이동에 따른 연조직 pogonion의 후방 이동은 양악 수술군에서 98%, 편악 수술군에서 109%로 편악 수술군에서 더 크게 나타났다. 양악 수술군에서는 편악 수술군에 비하여 경조직의 변화에 수반하는 상순에서의 큰 변화가 나타났다. 편악 수술군에서는 상순의 변화는 미약하였으며, 하순 및 이부의 변화가 양악 수술군에 비해 두드러지게 나타났다.

• International Journal of Oral Biology
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• 제43권2호
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• pp.101-111
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• 2018

Understanding the classification of malocclusion is a crucial issue in Orthodontics. It can also help us to diagnose, treat, and understand malocclusion to establish a standard for definite class of patients. Principal component analysis (PCA) and k-means algorithms have been emerging as data analytic methods for cephalometric measurements, due to their intuitive concepts and application potentials. This study analyzed the macro- and meso-scale classification structure and feature basis vectors of 1020 (415 male, 605 female; mean age, 25 years) orthodontic patients using statistical preprocessing, PCA, random matrix theory (RMT) and k-means algorithms. RMT results show that 7 principal components (PCs) are significant standard in the extraction of features. Using k-means algorithms, 3 and 6 clusters were identified and the axes of PC1~3 were determined to be significant for patient classification. Macro-scale classification denotes skeletal Class I, II, III and PC1 means anteroposterior discrepancy of the maxilla and mandible and mandibular position. PC2 and PC3 means vertical pattern and maxillary position respectively; they played significant roles in the meso-scale classification. In conclusion, the typical patient profile (TPP) of each class showed that the data-based classification corresponds with the clinical classification of orthodontic patients. This data-based study can provide insight into the development of new diagnostic classifications.