• Imaging Science in Dentistry
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• 제37권2호
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• pp.103-110
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• 2007

Purpose: To examine the danger zone of mesial root of mandibular first molar of patient without extraction using CBCT (cone-beam computed tomography) to avoid the risk of root perforation. Materials and Methods: 20 mandibular first molars without caries and restorations were collected, CT images were obtained by CBCT ($PSR9000N^{TM}$, Asahi Roentgen Co., Japan), reformed and analyzed by V-work 5.0 (CyberMed Inc., Korea), Distance between canal orifice and furcation was measured. In cross sectional images at 3, 4 and 5 mm below the canal orifice, distal wall thickness of mesiobuccal canal (MB-D), distal wall thickness of mesiolingual canal (ML-D), distal wall thickness of central part (C-D), mesial wall thickness of mesiobuccal canal (MB-M) and mesial wall thickness of mesiolingual canal (ML-M) were measured, Results: The mean distance between the canal orifice and the furcation of the roots is 2.40 mm, Distal wall is found to be thinner than mesial wall. Mean dentinal wall thickness of distal wall is about 1 mm, The wall thickness is thinner as the distance from the canal orifice is farther. But significant differences are not noted between 4 mm and 5 mm in MB-D and C-D, MB-D is thinner than ML-D although the differences is not significant. Conclusion: The present study confirmed the anatomical weakness of distal surface of the coronal part of the mesial roots of mandibular first molar by CBCT and provided an anatomical guide line of wall thickness during endodontic treatment.

• 대한방사선치료학회지
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• 제30권1_2호
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• pp.35-40
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• 2018

목 적 : 본원에서 사용하는 양성자 에너지는 크기에 따라 도달거리가 달라지며, Compensator는 Distal 두께에 따라 Energy의 크기를 다르게 할 수 있으며 이로 인해 Dose rate이 변화된다. 따라서 Compensator distal의 두께를 변화시키면서 Dose 분포 및 Beam on time에 대한 영향을 평가해보고자 한다. 대상 및 방법 : 본원에서 양성자치료를 받은 에너지가 낮은 환자 5명을 대상으로 실험하였다. 선택된 환자들의 기존 치료 시 Beam on time을 확인하였으며 이 후 양성자치료계획시스템(TPS)을 통하여 Compensator의 Distal 두께를 기존 두께에서 2 cm씩 최대 14 cm까지 증가시켜가며 치료계획을 비교 평가하였다. Dose 분포를 평가하기 위하여 Target의 Conformity Index(CI)값과 Homogeneity Index(HI)값, Target 후면부의 Organ at risk(OAR)의 최대선량을 비교하였으며 치료시간에 대한 영향을 평가하고자 Compensator Distal 두께 별로 제작하여 Beam on time을 비교하여 평가하였다. 결 과 : Compensator의 Distal 두께를 증가시켜 Homogeneity Index, Conformity Index를 분석한 결과 모든 환자에서 동일한 수치가 나왔다. Target 후면부의 OAR을 비교한 결과 Abdomen의 Spine cord에 최대 7 cGy, Eyeball의 RT Lens에서 88 cGy, Nasal cavity의 RT Lens에 391 cGy, Mediastinum의 Trachea에 51 cGy, Pelvis의 Small bowl에 661 cGy 증가하였다. Beam on time을 비교한 결과 Abdomen의 경우 기존 126초에서 최대 62초, Eyeball의 경우 105초에서 37초, Nasal cavity의 경우 기존 187초에서 134초, Mediastinum의 경우 기존 100초에서 40초, Pelvis의 경우 기존 440초에서 118초로 감소하였다. 결 론 : 연구결과 Compensator의 distal 두께가 두꺼워질수록 에너지의 크기를 증가시킬 수 있으며 Dose rate이 증가하여 Beam on time이 감소하는 효과가 있었다. 이는 Beam on time이 많이 소요되는 호흡동조치료를 요하는 Liver, 마취를 하는 소아환자에게 적용한다면 치료시간 단축과 환자의 편의성 면에서 큰 도움을 줄 것으로 평가된다. 하지만 에너지의 크기가 증가할수록 Distal penumbra가 증가하기 때문에 Target 후면부에 OAR이 인접해 있는 경우는 양성자치료계획 시 Penumbra의 영향을 고려한 적절한 Compensator 두께를 설정할 필요가 있을 것으로 사료된다.

• Archives of Plastic Surgery
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• 제42권3호
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• pp.327-333
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• 2015

Background An anatomical analysis of the transverse carpal ligament (TCL) and the surrounding structures might help in identifying effective measures to minimize complications. Here, we present a surgical technique based on an anatomical study that was successfully applied in clinical settings. Methods Using 13 hands from 8 formalin-fixed cadavers, we measured the TCL length and thickness, correlation between the distal wrist crease and the proximal end of the TCL, and distance between the distal end of the TCL and the palmar arch; the TCL cross sections and the thickest parts were also examined. Clinically, fasciotomy was performed on the relevant parts of 15 hands from 13 patients by making a minimally invasive incision on the distal wrist crease. Postoperatively, a two-point discrimination check was conducted in which the sensations of the first, second, and third fingertips and the palmar cutaneous branch injuries were monitored (average duration, 7 months). Results In the 13 cadaveric hands, the distal wrist crease and the proximal end of the TCL were placed in the same location. The average length of the TCL and the distance from the distal TCL to the superficial palmar arch were $35.30{\pm}2.59mm$ and $9.50{\pm}2.13mm$, respectively. The thickest part of the TCL was a region 25 mm distal to the distal wrist crease (average thickness, $4.00{\pm}0.57mm$). The 13 surgeries performed in the clinical settings yielded satisfactory results. Conclusions This peri-TCL anatomical study confirmed the safety of fasciotomy with a minimally invasive incision of the distal wrist crease. The clinical application of the technique indicated that the minimally invasive incision of the distal wrist crease was efficacious in the treatment of the carpal tunnel syndrome.

• Archives of Plastic Surgery
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• 제37권6호
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• pp.835-838
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• 2010

Purpose: Reconstruction of soft tissue defects in the distal lower leg, especially in the distal third, largely depends on free tissue transfer and local fasciocutaneous flaps. But several local muscle flaps have also been proposed as useful alternative reconstructive manner. In this report, the authors present the successful use of the flexor digitorum longus muscle flaps in the distal lower leg reconstruction. Methods: Case 1: An 81-year-old woman with a dog bite wound in the left distal lower leg was admitted. She had a $10{\times}8\;cm$ wound with tibial exposure along the medial aspect of the leg. Soft tissue reconstruction with a flexor digitorum longus muscle flap and a split-thickness skin graft was performed. Case 2: A 77-year-old woman had a squamous cell carcinoma in the right distal lower leg. After wide excision, a $5{\times}4\;cm$ wound was developed with exposure of the tibia. The flexor digitorum longus muscle flap was transposed and covered with a split-thickness skin graft. Results: The flexor digitorum longus muscle flaps were shown to be useful to cover tibial defects in the distal lower leg. During the follow-up period, no significant donor site morbidity was found. Conclusion: The flexor digitorum longus muscle flap can be used to cover the exposed distal tibia, especially when a free tissue transfer is not an option. The relative ease of dissection and minimal functional deficits were the major advantages of this flap, while the extent of reach into the lower third has a limitation.

• Clinics in Shoulder and Elbow
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• 제21권3호
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• pp.138-144
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• 2018

Background: Subacromial erosion remains a major concern after surgical fixation of acromioclavicular (AC) joint using a clavicular hook plate. To minimize postoperative subacromial erosion, we investigated the structural relationship between distal clavicle and acromion around the AC joint by considering the surgical fixation of the joint using the hook plate technique. Methods: Computed tomography scans of 101 AC joints without any inherent pathology were analyzed. The angle between the distal clavicle and acromion around the AC joint (AC angle), depth of the acromion, differences in height between distal clavicle and acromion (AC height difference), and thickness of distal clavicle and acromion at the AC joint were measured. Descriptive statistics were calculated for each anatomical parameter, and all results were compared between gender groups. Results: The mean AC angle was $17.1^{\circ}$(range, $-8.0^{\circ}$ to $39.0^{\circ}$), and the mean AC height difference was 3.5 mm (range, -0.7 to 8.7 mm). Both factors showed very high variability (coefficients of variation=62.6% and 46.6%, respectively). The mean AC angle was significantly higher in the female gender than in the male gender ($19.8^{\circ}$ vs. $13.8^{\circ}$, p=0.048). The mean acromion thickness and distal clavicular thickness were both significantly thinner in the female group than in the male group (p<0.001). Conclusions: Taken together, we believe our results might be helpful in minimizing postoperative subacromial erosion when performing surgical fixation of the AC joint using the hook plate, and be valuable in improving future design of the hook plate.

• 대한치과교정학회지
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• 제51권6호
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• pp.387-396
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• 2021

Objective: To identify optimal areas for the insertion of extra-alveolar miniscrews into the infrazygomatic crest (IZC) and mandibular buccal shelf (MBS), using cone beam computed tomography (CBCT) imaging in patients with different craniofacial patterns. Methods: CBCT reconstructions of untreated individuals were used to evaluate the IZC and MBS areas. The participants were divided into three groups, based on the craniofacial pattern, namely, brachyfacial (n = 15; mean age, 23.3 years), mesofacial (n = 15; mean age, 19.24 years), and dolichofacial (n = 15; mean age, 17.79 years). In the IZC, the evaluated areas were at 11, 13, and 15 mm above the buccal cusp tips of the right and left first molars. In the MBS, the evaluated areas were at the projections of the first molars' distal roots and second molars' mesial and distal roots, at a 4- and 8-mm distance from the cementoenamel junction. Intergroup comparisons were performed with analysis of variance and the Tukey test. Results: There was no statistically significant difference in the IZC bone thickness among the groups. For MBS bone availability, some comparisons revealed no difference; meanwhile, other comparisons revealed increased MBS bone thickness in the brachyfacial (first molars distal roots) and dolichofacial (second molars mesial and distal roots) patterns. Conclusions: There was no significant difference in the IZC bone thickness among the groups. The facial skeletal pattern may affect the availability of ideal bone thickness for the insertion of extra-alveolar miniscrews in the MBS region; however, this variability is unlikely to be clinically meaningful.

• Clinics in Shoulder and Elbow
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• 제2권2호
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• pp.138-142
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• 1999

Coracoclavicular ligament is main restraint to superior instability of the distal clavicle. Coracoacromial ligament, extensor tendon of toe, palmaris longus tendon, and Dacron tape have been used to reconstruct coracoclavicular ligament. We used semitedinosus tendon to reconstruct coracoclavicular ligament. The semitendinosus tendon was harvested as a usual fashion. After the distal clavicle and coracoid process were exposed, a hole of six millimeter diameter was made on the center of whole thickness of the distal clavicle. A malleolar screw was fixed from distal clavicle to coracoid process to maintain the reduced position of the acromioclavicular joint. The leading suture of tendon graft was passed through the hole of the distal clavicle and looped under the coracoid process. After leading portion of ten­don graft was looped over the clavicle, sutures were made between each end of the tendon graft with nonabsorbable suture materials.

• 대한족부족관절학회지
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• 제17권2호
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• pp.136-142
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• 2013

Purpose: To analyze the outcome of distal tibia fracture treated with the Distal Tibia LCP with combination of interfragmentary screw. Materials and Methods: Between January 2008 and March 2012, data of 34 patients with fracture of distal tibia treated with the Distal Tibia LCP with or without combination of interfragmentary screws were reviewed. There were 17 males and 17 females with an average age of 51.8 years (range, 18~77 years). Radiographic union time and time from surgery until ability to full weight bearing were measured and compared. Callus index was measured as quotient of callus thickness and diameter of corticalis both in AP and sagittal direction. Results: 12 fractures were treated with interfragmentary screws and 22 fractures were treated with bridging plate alone. In interfragmentary fixation group, time to full weight bearing was 14 weeks versus 15.75 weeks without screw. Callus index at bearing was not significantly lesser in patients with screw compated with those without, but callus index difference at posterative 4weeks was sigficant. Radiologic union time was 11.3 weeks in interfragmentary fixation group and 12.58 weeks without screw. Conclusion: The osteosynthesis with the Distal tibia LCP with combination of interfragmentary screw seems to be more stable in postoperative 4weeks than Distal tibia LCP alone, expecting to earlier ROM exercise and rehabilitation.

• 대한치과교정학회지
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• 제51권1호
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• pp.23-31
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• 2021

Objective: To evaluate the mandibular buccal shelf (MBS) in terms of the angulation and bone depth and thickness according to sex, age, and sagittal and vertical skeletal patterns in a Colombian population using cone-beam computed tomography (CBCT). Accordingly, the optimal site for miniscrew insertion in this area was determined. Methods: This descriptive, retrospective study included 64 hemi-arches of 34 patients. On CBCT images, the angulation, buccal bone depth (4 and 6 mm from the cementoenamel junction [CEJ] of MBS), and buccal bone thickness (6 and 11 mm from the CEJ of MBS) were measured at the mesial and distal roots of the mandibular first and second molars. Results: There were no statistically significant differences in the angulation, depth, and thickness of MBS between male and female patients. The values for the bone around the distal root of the mandibular second molar were significantly greater than the other values. The osseous characteristics were significantly better in participants aged 16-24 years. Class III patients exhibited the best osseous characteristics, with the bone depth at 6 mm being significantly different from that in Class I and Class II patients. Although values tended to be greater in patients with low angles, the difference was not statistically significant. Conclusions: MBS provides an optimal bone surface for miniscrew insertion, with better osseous characteristics at the distal root of the mandibular second molar, 4 mm from CEJ. Adolescent patients, Class III patients, and patients with a low angle exhibit the most favorable osseous characteristics in the MBS area.

• Archives of Plastic Surgery
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• 제38권6호
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• pp.829-835
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• 2011

Purpose: The two major concerns in skin grafting are poor color match in the recipient site and the donor site morbidity. And, glabrous skin on the palmar aspect of the hands and plantar aspect of the feet attributes define the skin on the palm and fingers sole as functionally and aesthetically different from skin on other parts of the body. When there is a glabrous skin defect, it should be replaced with similar skin to restore function and aesthetics. The palmar crease areas were used to minimize these problems. The purpose of this study is to present the precise surgical technique of the full thickness skin graft using distal palmar and midpalmar creases for aesthetic better outcome for hand injuries. Methods: From May 2006 to April 2010, 10 patients with 11 defects underwent glabrous full thickness skin grafting of finger defects. Causes included seven machinery injuries, two secondary burn reconstructions, and one knife injury. Donor sites included ten glabrous full thickness skin graft from the distal palmar crease and one from the midpalmar crease. Results: Follow-up ranged from 3 months to 24 months. All glabrous skin grafts demonstrated complete taking the recipient sites and no incidence of the complete or partial loss. The donor site healed without complications, and there were no incidences of significant hypopigmantation, hyperpigmentation, or hypertrophic scarring. Conclusion: The important aspects of this method involve immediate return of glabrous skin to the defect site and restoration of the recipient site's crease by simple primary closure from adjacent skin. The glabrous skin of the palm provides the best tissue match for the reconstruction of the hands, but only a limited amount of tissue is available for this purpose. Full thickness skin grafting using palmar crease of the defects is the ideal way of reconstructing glabrous skin to restore both function and aesthetics and minimize donor site morbidity.