• 대한치과교정학회지
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• 제22권3호
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• pp.531-556
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• 1992

The majority of the commonly used protraction headgears for the protraction of small and/or retropositioned maxilla not allow a change in the point of force application or direction of the force delivery to attain predictable results because of the position of the upper and lower lips to avoid discomfort to the patient. The purpose of this study was to investigate the initial reaction of maxillofacial complex according to the change of force variables such as direction and point of force application with designing an antenna type-modified protraction head gear. A macerated human skull with well aligned upper teeth was used to experimental model and the investigation was done by double exposure holographic interferometry. Fringe patterns of each protraction conditions were compared and analized. The results were as follows. (Frontal view) 1. The Counterclockwise rotation of the maxilla was showed by parallel protraction to occlusal plane and the fringe was decreased in number as higher point of force application. 2. Generally, the number of fringe was increased in 500gm of protraction force than in 300gm. 3. When apply the protraction force to the maxilla with rapid palatal expansion, the direction of fringe patterns was differed from the protraction without expansion. 4. In most of cases, the counterclockwise rotation was decreased in case of the direction of the force is $20^{\circ}$ downward to occlusal plane compared to the parallel direction. 5. At the point of force application is 15mm above and the direction of force is 20 downward to occlusal plane , the translation of the maxillary complex was showed. (Lateral view) 6. The direction of fringe patterns of the facial bones were differed each other by the sutures, and showed almost parallel when apply the 300gm and 500gm of protraction force. 7. In case of rapid palatal expansion with protraction of the maxilla, the fringe patterns between the maxillary area and the area from the posterior of the maxillary first molar to the pterygomaxillary fissure were differed. In case without rapid palatal expansion, the changes of direction and point of the force application did not affect to the direction and the number of the fringe patterns.

• 대한치과교정학회지
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• 제32권6호
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• pp.425-434
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• 2002

이 연구의 목적은 유년기 건조 두개골에서 상악골 전방 견인 장치로 상악골의 저항중심을 지나는 힘을 가했을 때, 상악 골 복합체의 공간 변화를 평가하기 위함이다. 유치열기 혹은 초기 혼합 치열기로 추정되는 건조 두개골 4구를 사용하여 Delare의 facemask로 modified protraction headgear를 제작하였으며, 각각의 두개골에서 알지네이트 인상을 채득한 후 상악 스플린트를 제작하였다. 전방 견인력을 편측 당 1000gm씩 6시간 가하였다. 전방견인 전과 후 측모 두부방사선사진을 촬영하였으며 정확한 중첩이 가능하도록 1.5mm 길이의 $.017\times.025$TMA wire를 사용하여 9개의 reference marker를 두개골 우측에 위치 시켰다. 본 연구를 통해 상악골 전방 견인시 상악골 복합체의 전방 이동과 더불어 수직적 변화를 관찰할 수 있었으며, protraction headgear의 주된 효과는 상악골의 반시계 방향의 회전, 즉 구개상악부(palatomaxillary region)의 전하방 경사 이동에 의한 것임을 알 수 있었다.

• 대한소아치과학회지
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• 제23권3호
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• pp.667-673
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• 1996

The prevalence of class III malocclusion is approximately 5$\sim$9%, and about one fourth of this malocclusion is due to underdeveloped maxilla. Maxillary protraction appliance is an orthopedic device which promote the growth of a deficient maxilla by applying extraoral force to actively growing patients. The object of using maxillary protraction appliance is to guide a normal growth of maxilla and mandible and improve the occlusal relationship and also improve the facial profile. The author treated three patients whom were diagnosed as a class III malocclusion due to deficient maxilla using maxillary protraction appliance and the followings are the conclusions : 1. In these cases, anterior crossbite was corrected by anterior movement of maxilla and downward backward rotation of mandible and simultaneously, anterior facial height was increased. 2. The amount of dental change compare to skeletal change was greater as the patients got older. 3. When 500gm of force to each side was applied, the treatment period has been decreased. 4. As a result of applying the force between maxillary first primary molar and canine, there was a small degree of changes in palatal plane. So, it can be concluded that the maxillary protraction appliance is effective in treating growing patients with a deficient maxilla.

• 대한치과교정학회지
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• 제52권5호
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• pp.313-323
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• 2022

Objective: This study aimed to estimate the clinical effects of different types of bone-anchored maxillary protraction devices by using a network meta-analysis. Methods: We searched seven databases for randomized and controlled clinical trials that compared bone-anchored maxillary protraction with tooth-anchored maxillary protraction interventions or untreated groups up to May 2021. After literature selection, data extraction, and quality assessment, we calculated the mean differences, 95% confidence intervals, and surface under the cumulative ranking scores of eleven indicators. Statistical analysis was performed using R statistical software with the GeMTC package based on the Bayesian framework. Results: Six interventions and 667 patients were involved in 18 studies. In comparison with the tooth-anchored groups, the bone-anchored groups showed significantly more increases in Sella-Nasion-Subspinale (°), Subspinale-Nasion-Supramentale(°) and significantly fewer increases in mandibular plane angle and the labial proclination angle of upper incisors. In comparison with the control group, Sella-Nasion-Supramentale(°) decreased without any statistical significance in all treated groups. IMPA (angle of lower incisors and mandibular plane) decreased in groups with facemasks and increased in other groups. Conclusions: Bone-anchored maxillary protraction can promote greater maxillary forward movement and correct the Class III intermaxillary relationship better, in addition to showing less clockwise rotation of mandible and labial proclination of upper incisors. However, strengthening anchorage could not inhibit mandibular growth better and the lingual inclination of lower incisors caused by the treatment is related to the use of a facemask.

• 대한구순구개열학회지
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• 제11권1호
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• pp.37-48
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• 2008

Cleft lip and palate patients often develop maxillary retrusion due to the combined effects of the congenital deformity and the scar tissue after surgical repairs. Maxillary protraction in the cleft patients using orthopedic appliances (i.e. face mask) or distraction osteogenesis during early childhood helps to achieve more balanced skeletal harmony and favorable occlusion for future growth to occur. Kinds, indication, protocol for use of the traditional orthopedic appliances will be discussed. Also the facemask with miniplate system recently developed will be introduced.

• 대한치과교정학회지
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• 제42권5호
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• pp.235-241
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• 2012

Objective: The purpose of this study was to evaluate the validity of the 3-dimensional (3D) superimposition method of digital models in patients who received treatment with rapid maxillary expansion (RME) and maxillary protraction headgear. Methods: The material consisted of pre- and post-treatment maxillary dental casts and lateral cephalograms of 30 patients, who underwent RME and maxillary protraction headgear treatment. Digital models were superimposed using the palate as a reference area. The movement of the maxillary central incisor and the first molar was measured on superimposed cephalograms and 3D digital models. To determine whether any difference existed between the 2 measuring techniques, intra-class correlation (ICC) and Bland-Altman plots were analyzed. Results: The measurements on the 3D digital models and cephalograms showed a very high correlation in the antero-posterior direction (ICC, 0.956 for central incisor and 0.941 for first molar) and a moderate correlation in the vertical direction (ICC, 0.748 for central incisor and 0.717 for first molar). Conclusions: The 3D model superimposition method using the palate as a reference area is as clinically reliable for assessing antero-posterior tooth movement as cephalometric superimposition, even in cases treated with orthopedic appliances, such as RME and maxillary protraction headgear.

• 대한치과의사협회지
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• 제54권3호
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• pp.217-229
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• 2016

Purpose: The aim of this study was to evaluate the soft-tissue change after the maxillary protraction therapy using threedimensional (3D) facial images. Materials and Methods: This study used pretreatment (T1) and posttreatment (T2) 3D facial images from thirteen Class III malocclusion patients (6 boys and 7 girls; mean age, $8.9{\pm}2.2years$) who received maxillary protraction therapy. The facial images were taken using the optical scanner (Rexcan III 3D scanner), and T1 and T2 images were superimposed using forehead area as a reference. The soft-tissue changes after the treatment (T2-T1) were three-dimensionally calculated using 15 soft-tissue landmarks and 3 reference planes. Results: Anterior movements of the soft-tissue were observed on the pronasale, subnasale, nasal ala, soft-tissue zygoma, and upper lip area. Posterior movements were observed on the lower lip, soft-tissue B-point, and soft-tissue gnathion area. Vertically, most soft-tissue landmarks moved downward at T2. In transverse direction, bilateral landmarks, i.e. exocanthion, zygomatic point, nasal ala, and cheilion moved more laterally at T2. Conclusion: Facial soft-tissue of Class III malocclusion patients was changed three-dimensionally after maxillary protraction therapy. Especially, the facial profile was improved by forward movement of midface and downward and backward movement of lower face.

• 대한치과교정학회지
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• 제53권3호
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• pp.175-184
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• 2023

Objective: To evaluate and compare a series of volume changes in the nasal cavity (NC), nasopharynx, oropharynx, and maxillary sinuses (MS) in growing Class III patients after either rapid palatal expansion (RPE) or alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy, by using cone-beam computed tomography (CBCT). Methods: Forty growing Class III patients were retrospectively selected and divided into two matched groups: RPE/FM (14 females, 6 males; mean age, 9.66 ± 1.23 years) and Alt-RAMEC/FM groups (14 females, 6 males; mean age, 10.28 ± 1.45 years). The anteroposterior and vertical displacements of Point A, the volumes of the NC, nasopharyngeal, oropharyngeal, and MS were measured at different time points: pretreatment (T1), postexpansion (T2), and postprotraction (T3). Results: Both groups demonstrated significant maxilla advancement (by 1.3 mm) during expansion, with a statistically significant intergroup difference during protraction (RPE/FM, 1.1 mm; Alt-RAMEC/FM, 2.4 mm; p < 0.05) and throughout the treatment (RPE/FM, 2.4 mm; Alt-RAMEC/FM, 3.7 mm; p < 0.05). NC and nasopharyngeal airway volumes increased significantly in both groups after expansion, protraction, and treatment. The oropharyngeal and MS volumes increased in both groups after protraction and post-treatment. However, no volumetric differences were observed between the two groups. Conclusions: There was no significant difference in airway volume changes, including NC, nasopharyngeal, oropharyngeal airway, and MS, between RPE/FM and Alt-RAMEC/FM groups at different time points. Although there was significantly more forward movement after protraction in the Alt-RAMEC/FM group, the difference was deemed too small to be clinically relevant.

• 대한치과교정학회지
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• 제32권5호
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• pp.301-312
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• 2002

상악골 전방견인 장치를 이용한 골격성 III급 부정교합 환자의 악정형적 치료에서 치료시기는 치료효과에 지대한 영향을 미칠 수 있으며 이상적인 치료시기는 연구자에 따라 다소의 차이는 있으나 다른 형태의 부정교합보다는 다소 이른 사춘기 이전의 어린 나이라는 것이 선학들의 공통된 의견이었다 하지만 통계적 자료들을 바탕으로 한 최근의 논문들은 과거 선학들의 의견을 뒷받침 해주는 논문과 그렇지 않은 논문들로 나뉘고 있어 이상적 치료시기에 대한 정립된 의견이 없는 실정이다. 이에 본 연구에서는 119명의 환자들의 수완부골 방사선 사진을 평가하여 골성숙도에 따라 사춘기전군과 사춘기군으로 분류하고 치료전후 측모두부방사선 사진을 분석하여 상악골 전방견인에 대한 치료효과를 비교하였다. 평균 치료기간은 사춘기전군은 6.5개월, 사춘기군은 6.1개월이었으며 치료전후의 측모두부방사선 사진을 분석한 결과 다음과 같은 결론을 얻었다. 1. 상악골의 전방이동양은 사춘기전군과 사춘기군간에 차이가 없었다. 2. 상악골의 하방이동양은 사춘기전군과 사춘기군간에 차이가 없었다. 3. 하악골의 하방이동양과 후하방회전양은 사춘기전군과 사춘기군간에 차이가 없었다. 4. 치성이동양은 사춘기전군과 사춘기군간에 차이가 없었다. 이상의 결과로 사춘기전 뿐 아니라 사춘기에서도 상악골 전방견인에 의해 상악골 성장촉진과 함께 성공적인 악정형 치료가 가능함을 알 수 있었다.

• 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.