• 대한치과보철학회지
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• 제40권1호
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• pp.18-29
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• 2002

As the inaccuracy which was made in implant impression prevented passive fit, it needed to solder the sectioned framework at several locations to correct the inaccuracy. Many clinicians have suggested impression techniques which could make passive fit between implant and superstructure. The purpose of this research was to measure and compare the accuracy of three methods of taking impression with the strain amplifier. The experimental groups were classified as follows : Group I : splinted the two parts with $Futar^{(R)}D$ Occlusion. Group II : splinted the two parts with $DuraLay^{(R)}$. Group III ; didn't splint the two parts. The results were as follows ; 1. The values of strain in the vertical and horizontal surfaces were increased in the order of group I, group II and group III. 2. Group 1 showed higher accuracy of the duplicated casts in the vortical and horizontal sur faces than group II and group III (p<0.05). 3. There were no significant differences in the accuracy of the duplicated casts between group II and group III. From the above results, it is considered that the splinting method of impression copings could make an influence on the accuracy of the master casts. To improve the accuracy of the master casts, splinting the squared impression copings with the additional silicone occlusion materials is recommendable.

• Archives of Plastic Surgery
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• 제42권5호
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• pp.532-543
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• 2015

Capsular contracture is the most common complication following implant based breast surgery and is one of the most common reasons for reoperation. Therefore, it is important to try and understand why this happens, and what can be done to reduce its incidence. A literature search using the MEDLINE database was conducted including search terms 'capsular contracture breast augmentation', 'capsular contracture pathogenesis', 'capsular contracture incidence', and 'capsular contracture management', which yielded 82 results which met inclusion criteria. Capsular contracture is caused by an excessive fibrotic reaction to a foreign body (the implant) and has an overall incidence of 10.6%. Risk factors that were identified included the use of smooth (vs. textured) implants, a subglandular (vs. submuscular) placement, use of a silicone (vs. saline) filled implant and previous radiotherapy to the breast. The standard management of capsular contracture is surgical via a capsulectomy or capsulotomy. Medical treatment using the off-label leukotriene receptor antagonist Zafirlukast has been reported to reduce severity and help prevent capsular contracture from forming, as has the use of acellular dermal matrices, botox and neopocket formation. However, nearly all therapeutic approaches are associated with a significant rate of recurrence. Capsular contracture is a multifactorial fibrotic process the precise cause of which is still unknown. The incidence of contracture developing is lower with the use of textured implants, submuscular placement and the use of polyurethane coated implants. Symptomatic capsular contracture is usually managed surgically, however recent research has focussed on preventing capsular contracture from occurring, or treating it with autologous fat transfer.

• 대한기계학회논문집B
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• 제36권11호
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• pp.1111-1117
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• 2012

이상적인 코 보형물은 환자가 원하는 모양을 그대로 재현하면서, 그 상태를 안정적으로 유지할 수 있는 재료적 특성을 지녀야 한다. 현재 보편적으로 사용되고 있는 실리콘 코 보형물은 면역 반응이나 피부를 뚫고 돌출하는 문제점 등이 보고되고 있다. 이러한 부작용을 최소화하기 위해 본 연구에서는 조직공학 기술을 이용하여 새로운 코 성형술을 제안하고자 한다. 조직공학 기반의 코 성형술의 가능성을 확인하기 위해 코 보형물 형상의 인공지지체를 상용 CAD 소프트웨어와 자유형상제작 기술 중에 하나인 다축 적층 시스템을 이용하여 설계 및 제작하였다. 그리고 코 성형술 인공지지체로서의 사용이 적합한지 확인하기 위해 비중격 유래 연골 세포를 이용하여 세포 증식, 기능 실험을 수행하였다.

• 대한치과보철학회지
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• 제45권3호
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• pp.389-400
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• 2007

Statement of problem. Use of the conventional dental impression procedure is problematic in patients who have difficulty opening their mouth, difficulty breathing through their nose or tendency to gag. Purpose. It is necessary to make individual trays more comfortable for patients during impression taking procedure. It was reported at the KAP Annual Meeting 2001 Seoul that an improved impression technique was suitable for this purpose. In this study, the accuracy of the improved dental impression method for implant was compared with the conventional dental impression method. Material and methods. An oral simulator was made from clear acrylic resin block which had similar form of edentulous ridge. For setting up the standard, five fixtures were installed on it. Study casts were made using two kinds of impression techniques. One was the conventional method that was taken using silicone impression material and an individual resin tray under connection of inter-fixture relation. The other was the improved method in which was the connection of the impression coping and the thermoformed polymethyl methacrylate tray. In addition, two different study casts were made from the improved impression body. The coordinates of the fixture on the study model were measured by three-dimensional coordinate measuring equipment. Then the distances between each fixture were calculated and compared with that of oral simulator. Accuracy of the each impression method was also assessed. Results. The differences of inter-fixture dimension between study casts and simulator in the improved impression technique showed $0.014{\pm}0.016mm$ and $0.017{\pm}0.022mm$, respectively and that of the conventional method was $0.017{\pm}0.014mm$. There was no significant difference between the improved impression technique and conventional method. Conclusion. The improved impression technique is useful for multiple support implants.

• Archives of Plastic Surgery
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• 제34권2호
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• pp.222-228
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• 2007

Purpose: Report of the good results of breast reconstruction using Becker permanent tissue expander that showed a short operation time and a quick post-operation recovery time, little side effects and usually superb aesthetic results without the need for additional incisions or donor site morbidity. The authors, after carrying out breast reconstruction operations using Becker permanent tissue expander on patients with appropriate indications, attempted to analyze several factors such as complication rates and patient satisfaction measurements. Methods: 11 cases of breast reconstruction using Becker expander implants were carried out on a total of 10 patients between March 2000 and February 2003. The patients were followed up at outpatient visit for an average of 6 months. Results: The most common post-operation complication was pain resulting from saline injection into the expanders, complained by 5 patients(50%). rib fractures, skin necrosis, implant removal due to infection, and breast cancer recurrence each occurred in 1 patient (9.9%). There was no occurrence of skin contracture complications which occurs frequently in case of silicone implant insertion. Patient complacency was surveyed by patient interviews made right after the operations and during outpatient follow-up periods: 5(50%) patients out of 10 showed excellent, 3(30%) good, and 2(20%) showed fair, leaving no patients who were disappointed with operation results. On routine follow-up, 80% of patients expressed satisfaction with the cosmetic outcome of their post-mastectomy beast reconstruction. Conclusion: Breast reconstruction using the Becker expander is a reliable alternative to other reconstructive methods but good patient selection is essential for satisfactory results.

• Archives of Plastic Surgery
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• 제49권3호
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• pp.373-377
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• 2022

Currently, robot-assisted latissimus dorsi muscle flap (RLDF) surgery is used in treating patients with Poland syndrome and for breast reconstruction. However, conventional RLDF surgery has several inherent issues. We resolved the existing problems of the conventional system by introducing the da Vinci single-port system in patients with Poland syndrome. Overall, three patients underwent RLDF surgery using the da Vinci single-port system with gas insufflation. In the female patient, after performing RLDF with silicone implant, augmentation mammoplasty was also performed on the contralateral side. Both surgeries were performed as single-port robotic-assisted surgery through the transaxillary approach. The mean operating time was 449 (335-480) minutes; 8.67 (4-14) minutes were required for docking and 59 (52-67) minutes for robotic dissection and LD harvesting. No patients had perioperative complication and postoperative problems related to gas inflation. The single-port robot-assisted surgical system overcomes the drawbacks of previous robotic surgery in patients with Poland syndrome, significantly shortens the procedure time of robotic surgery, has superior cosmetic outcomes in a surgical scar, and improves the operator's convenience. Furthermore, concurrent application to another surgery demonstrates the possibility in the broad application of the robotic single-port surgical system.

• 대한치과보철학회지
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• 제46권2호
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• pp.201-208
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• 2008

연구목적: 시멘트 유지형 지대주를 인상용 코핑으로 이용하고 레진이나 금속 구조물에 접착하여 스플린팅하는 새로운 인상법을 시도하였다. 연구의 목적은 첫 번째, 3개의 임플랜트가 $15^{\circ}$ 경사지게 식립된 모형에서 closed tray 인상법과 레진 스플린팅한 open tray 인상법의 정확성을 비교하는 것이고 두 번째, 새로운 인상법의 정확성을 앞의 두 가지 인상법과 비교하는 것이다. 연구 재료 및 방법: 3개의 임플랜트 아날로그가 선상으로 배열되고 가운데 아날로그는 모형에 수직이고 양쪽 끝 아날로그는 이것에 앞뒤로 $15^{\circ}$ 경사지게 배열된 주모형과 주모형에 잘 적합되는 기준구조물을 제작하였다. closed tray 인상법, 레진 스플린팅한 open tray 인상법, 지대주-레진구조물 접착 인상법, 지대주-금속구조물 접착 인상법, 각 10개씩 40번의 인상을 채득하여 복제모형을 제작하였다. 이미지 처리할 수 있는 광학 현미경을 이용하여 기준구조물과 복제모형내의 아날로그와의 수직간격을 측정하여 인상의 정확성을 평가하였다. 통계처리는 one-way ANOVA와 사후 검정으로 Tukey test를 5% 유의수준으로 시행하였다. 결과: closed tray 인상법;74.3 (${\pm}33.4$)${\mu}m$의 간격은 레진 스플린팅한 open tray 인상법과 다른 두 가지 새로운 인상법보다 간격의 크기가 통계적 유의성 있게 컸다(P<.05). 지대주-금속구조물 접착 인상법;42.5 (${\pm}11.9$)${\mu}m$은 다른 인상법들 보다 간격의 크기가 통계적 유의성 있게 작았다(P<.05). 지대주-레진구조물 접착 인상법;51.0 (${\pm}14.1$)${\mu}m$은 레진 스플린팅한 open tray 인상법50.3 (${\pm}16.9$)${\mu}m$과 통계적 유의성 있는 차이를 보이지 않았다(P>.05). 결론: 이 연구의 한계 내에서, 레진 스플린팅한 open tray 인상법은 closed tray 인상법보다 우수한 정확성을 나타내었고, 지대주를 금속구조물에 접착하는 새로운 인상법의 정확성은 레진 스플린팅한 open tray 인상법보다 우수하였다.

• Journal of Periodontal and Implant Science
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• 제48권3호
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• pp.152-163
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• 2018

Purpose: To determine whether the swelling and mechanical properties of osmotic self-inflating expanders allow or not the induction of intraoral soft tissue expansion in dogs. Methods: Three different volumes (0.15, 0.25, and 0.42 mL; referred to respectively as the S, M, and L groups) of soft tissue expanders (STEs) consisting of a hydrogel core coated with a silicone-perforated membrane were investigated in vitro to assess their swelling behavior (volume swelling ratio) and mechanical properties (tensile strength, tensile strain). For in vivo investigations, the STEs were subperiosteally inserted for 4 weeks in dogs (n=5). Soft tissue expansion was clinically monitored. Histological analyses included the examination of alveolar bone underneath the expanders and thickness measurements of the surrounding fibrous capsule. Results: The volume swelling ratio of all STEs did not exceed 5.2. In tensile mode, the highest mean strain was registered for the L group ($98.03{\pm}0.3g/cm$), whereas the lowest mean value was obtained in the S group ($81.3{\pm}0.1g/cm$), which was a statistically significant difference (P<0.05). In addition, the S and L groups were significantly different in terms of tensile strength ($1.5{\pm}0.1g/cm$ for the S group and $2.2{\pm}0.1g/cm$ for the L group, P<0.05). Clinical monitoring showed successful dilatation of the soft tissues without signs of inflammation up to 28 days. The STEs remained volumetrically stable, with a mean diameter in vivo of 6.98 mm, close to the in vitro post-expansion findings (6.69 mm). Significant histological effects included highly vascularized collagen-rich fibrous encapsulation of the STEs, with a mean thickness of $0.67{\pm}0.12mm$. The bone reaction consisted of resorption underneath the STEs, while apposition was observed at their edges. Conclusions: The swelling and mechanical properties of the STEs enabled clinically successful soft tissue expansion. A tissue reaction consisting of fibrous capsule formation and bone loss were the main histological events.

• 대한치과보철학회지
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• 제36권2호
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• pp.379-388
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• 1998

본 연구는 악안면보철용 실리콘의 색안정성을 연구하기 위하여 실리콘 재료로 MDX 4-4210 Silicone(Dow Coming. Midland, Mich.)과 A-2186(Factor II, Lakeside, Az)을 사용하고 Mars Violet. Golden Yellow, Red yellow, Raw Sienna등 4종의 색소(Factor II, Lakeside, Az)를 이용하여 시편을 제작한 후 1군은 섭씨5-55도에서 700회 thermocycling하였고, 2군은 10%의 비눗물(Ivory, Proctor & Gamble Inc,. Toronto, Ontario)에 담아 섭씨15-55도에서 700회 thermocycling하였다. 3군은 10%의 비눗물에 담아 75일간 실온에서 보관하였으며 4군은 실온의 암실에 75일간 보관하였다. 5군은 초여름인 6월 중순부터 75일간 햇볕이 잘드는 곳에 위치하였다. 이를 측색색차계(Model TC-6FX, Tokyo Denshoku Co., Japan)를 이용하여 측정하고 색변화를 연구한 결과 다음과 같은 결론을 얻었다. 1. $L^*$값의 경우 모든 실험군에서 대조군에 비해 유의하게 감소하였다. 2. $a^*$값의 경우 대부분의 실험군에서 증가하였으나 Raw sienna, Mars violet색소를 사용한 실험 3.4.5군의 MDX4-4210의 경우 감소하는 경향을 보였다. 3. $b^*$값은 실험1.2.3군의 경우 대부분 감소하였고 실험4.5.군의 경우에서 증가하였으나 3.4.5군의 경우에서 대부분 유의한 차이가 없었다. 4. ${\Delta}E$의 값은 실험군에서 대부분 감소하였으나 4군의 A-2186에서 증가하는 경향을 보였고 실험2군의 Red yellow, Mars violet을 사용한 MDX4-4210에서 비교적 큰 변화를 보였다. 5. $L^{\ast}$값과 a값의 변화량의 합은 A-2186의 경우에서 크게 나타났으나 ${\Delta}E$값의 변화량은 MDX4-4210에서 크게 나타났다. 6. $L^*$값의 변화량의 합은 실험4군에서 크게 나타났으며 $a^*$값은 1군에서, $b^*$값과 ${\Delta}E$값의 변화량의 합은 2군에서 크게 나타났다.

• Archives of Plastic Surgery
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• 제41권4호
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• pp.362-365
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• 2014

Background Many implants are being used for the reconstruction of orbital wall fractures. The effect of the choice of implant for the reconstruction of an orbital wall fracture on the surgical outcome is under debate. The purpose of this article is to compare the outcomes of orbital wall reconstruction of small orbital wall fractures on the basis of the implants used. Methods The authors conducted a retrospective study using electronic databases. Between March 2001 and December 2012, 461 patients with orbital wall fractures were included in this study. Among them, 431 patients in whom the fracture size was less than $300mm^2$ were analyzed. The fracture size was calculated using computed tomography scans of the orbit in the sagittal and coronal images. Cases in which the fracture size was less than $300mm^2$ were included in this study. Results One hundred and twenty-nine patients were treated with silastic sheets; 238 patients were treated with titanium meshes; and absorbable meshes were used in the case of 64 patients. Overall, 13 patients required revision, and the revision rate was 3.0%. The revision rate of the silastic sheet group was 5.4%. In the multivariable analysis, the revision rate of the group reconstructed with silastic sheets was highly statistically significant (P=0.043, odds ratio=3.65). However, other factors such as age, sex, fracture type, and fracture size were not significant. Conclusions Reconstruction of orbital wall fractures with silastic sheets may cause more complications than that with other materials such as titanium meshes and absorbable meshes.