Restoration using dental CAD/CAM system in severe tooth wear patient: A case report

Wonjin Kee,Hyeran Kim,임현필,윤귀덕,박찬 조선대학교 치의학연구원 2018 Oral Biology Research (Oral Biol Res) Vol.42 No.4

In a situation where a vertical dimension has to be increased, the normal occlusion, function and aesthetics should be restored aftertaking into consideration the neuromuscular system and temporomandibular join. In order to do this, the provisional prosthesisshould be made according to the patient's information. Moreover, the period of adjustment should be made through the provisionalprosthesis modification, if necessary. The patient is then transferred to the final prosthesis to obtain results that are satisfactory. In themodern-day world, provisional prosthesis are replicated using three dimensional scanning and computer aided design/computer aidedmanufacturing (CAD/CAM) then made into final prosthesis. The adaptability of stomatognathic system can be judged by the PMMAprovisional restoration. Functional and aesthetical aspect can be obtained. The adjustment period can be shortened by an intraoralcorrection and proper wear between provisional restorations. By using the CAD/CAM technology that transfers the information rightinto the final prosthesis.

Fabrication of tunable silica-mineralized nanotubes using flagella as bio-templates

Jo, Wonjin,Freedman, Kevin J,Yi, Dong Kee,Kim, Min Jun IOP Pub 2012 Nanotechnology Vol.23 No.5

<P>Bacterial flagella are particularly attractive bio-templates for nanotubes due to their tubular structures and small inner and outer diameters. In this work, flagella isolated from Salmonella typhimurium were used as templates for silica-mineralized nanotubes. The process involved pretreatment of flagella with aminopropyltriethoxysilane (APTES), followed by the addition of tetraethoxysilane (TEOS). By controlling the concentration of TEOS and the reaction time, we developed a simple and precise method for creating silica-mineralized flagella nanotubes (SMFNs) with various thicknesses of the silica layer. It is demonstrated that flagella can be utilized for the fabrication of SMFNs with tunable thickness. A thicker silica layer was obtained as the concentration ratio of TEOS and reaction time was increased. The present experimental evidence has shown the feasibility of using such fabrication techniques to manufacture nanotubes without genetic modification of flagella which retain the original morphology.</P>

본연적 신축성을 갖는 발광 다이오드 개발 동향

고원진,최문기,Wonjin Koh,Moon Kee Choi 한국전기전자재료학회 2023 전기전자재료학회논문지 Vol.36 No.6

Intrinsically stretchable light-emitting diodes, composed of stretchable electrodes, charge transport layers, and luminescent materials, have garnered significant interest for enhancing human well-being and advancing the field of deformable electronics. Various luminescent materials, such as perovskites and organics, have been integrated with stretchable elastomers to function as the stretchable emissive layers in these intrinsically stretchable LEDs. Stretchable conductors including Ag nanowire based percolating structures and conducting polymers have been utilized as stretchable transparent electrode. Despite this progress, their performances in terms of efficiency and stability remain challenging compared to their structurally stretchable and rigid LED counterparts. This review offers a comprehensive overview of recent advancements in intrinsically stretchable LEDs, focusing on material innovations.

하악 편측 소수치 잔존 환자에서 임플란트 고정성 보철물을 사용하여 양측성 후방 연장 국소의치로 수복: 증례보고

기원진,박재호,임현필,윤귀덕,박상원,Kee, Wonjin,Park, Jae-Ho,Lim, Hyun-Pil,Yun, Kwi-Dug,Park, Sang-Won 대한치과보철학회 2019 대한치과보철학회지 Vol.57 No.2

편측 부분 무치악에서 소수의 치아로 지대치를 형성하여 가철성 국소의치 제작 시 환자의 불편함 및 지대치 손상 등으로 인해 만족도가 낮아질 수 있다. 최근 편측 부분 무치악에서 임플란트 고정성 보철물을 지대치로 사용하여 양측성 후방 연장 국소의치로 제작하는 방법이 보고되고 있다. 본 증례에서 임플란트 고정성 보철물을 사용하여 환자의 수직 악간관계를 보존하고 본인의 치아와 같은 형태를 부여하여 환자에게 심리적 안정감을 주며 향상된 저작 기능의 결과를 제공하였다. 또한 임플란트 고정성 보철물을 통하여 예후가 불량할 것으로 예상되는 편측성 후방 연장 국소의치를 역학적, 기능적으로 유리한 양측성 후방 연장 국소의치를 제작하였다. 국소의치의 지지, 유지, 안정 요소의 향상을 가져왔으며 환자에게 경제적 및 사용 시 만족감을 가져왔다. Traditional removable partial denture is a successful treatment for partial edentulous patients. When the abutment is formed with unilateral minority teeth, satisfaction with the use of removable partial denture may be lowered due to patient's discomfort and damage of the abutment. Recently, it has been reported that the unilateral posterior extension partial denture is used as a bilateral posterior extension partial denture using implant fixed prostheses as abutments. In this case, by using implant surveyed crown prostheses, bilateral posterior extension partial denture is fabricated in site that is predicted to have a poor prognosis. This resulted in improved support, maintenance, and stabilization of the removable partial denture, which were economically beneficial to patient and satisfied with use.

Two-terminal mechanical perovskite/silicon tandem solar cells with transparent conductive adhesives

Choi, In Young,Kim, Chan Ul,Park, Wonjin,Lee, Hyungmin,Song, Myoung Hoon,Hong, Kuen Kee,Seok, Sang Il,Choi, Kyoung Jin Elsevier 2019 Nano energy Vol.65 No.-

<P><B>Abstract</B></P> <P>Herein, we demonstrate a novel two-terminal perovskite/silicon mechanical tandem solar cell, fabricated by bonding a silicon cell upside down on a perovskite cell using a transparent conductive adhesive (TCA). The TCA consists of Ag-coated poly(methyl 2-methylpropenoate) microparticles embedded in a polymer adhesive. The Ag microparticles serve as an electrical current path, and the polymer adhesive mechanically bonds two sub-cells. The specific contact resistance and transmittance of the TCA layer were determined to be 5.46 × 10<SUP>−2</SUP> Ω∙cm<SUP>2</SUP> and >97.0%, respectively. Through an optical simulation, the current of the perovskite top cell was predicted to match the current of the p-type Si bottom cell with an Al back-surface field (BSF) layer when the thickness of MAPbI3 was 150 nm. The tandem cell fabricated under the optimal current matching conditions exhibited a current density of 15.43 mA cm-2, an open-circuit voltage of 1.59 V, and a fill factor of 79%, resulting in a steady-state efficiency of 19.4%. To the best of our knowledge, our result is the highest efficiency among two-terminal mechanical perovskite/silicon tandem cells. The unique structure of this tandem cell facilitates an excellent long-term stability without encapsulation in humid environment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel idea to fabricate a two-terminal mechanical tandem solar cell by using a transparent conductive adhesives. </LI> <LI> Transparent conductive adhesives make the commercial textured silicon cells easily be tandemized with perovskite cells. </LI> <LI> Optical simulation for current matching of two sub-cells. </LI> <LI> We propose strategies to achieve a higher efficiency (>24%) through PERC silicon cells and band-gap-tuned perovskite cells. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

스캔 및 밀링을 통해 기존 의치를 복제한 개인트레이를 이용한 흡착식 의치 제작 증례

박민혁,기원진,양홍서,박상원,윤귀덕,박찬,Park, Minhyuk,Kee, Wonjin,Yang, Hongso,Park, Sang-Won,Yun, Kwi-Dug,Park, Chan 대한치과보철학회 2020 대한치과보철학회지 Vol.58 No.3

In the case of complete edentulous patients, as the mandibular alveolar bone absorption progresses, the maintenance and stability of the existing dentures, which had satisfactory functions in the past, are deteriorated. Despite of the need to fabricate new dentures, they often hesitate due to physical burdens on the duration and intensity of future treatment progress due to the effects of aging and systemic diseases. In the case of these completely edentulous patients, it is necessary to consider the treatment goals that can reduce the number of visits and the adaptation period for new dentures before starting the treatment. This case is a case of producing complete dentures of elderly patients with deteriorated physical ability. In addition to producing suction dentures through preliminary and definitive closed mouth functional impression suggested by Sato, CAD / CAM technique was used to transfer occlusal functional information of existing dentures to facilitate adaptation to new dentures. 완전무치악 환자의 경우 하악 치조골 흡수가 진행됨에 따라, 과거 만족스러운 기능을 보였던 기존 총의치의 유지 및 안정이 저하된다. 총의치 재제작이 요구됨에도 불구하고, 증령 및 전신질환 등의 영향으로 향후 겪어야 할 진료의 기간과 강도에 대한 신체적 부담으로 인해 새 의치의 제작을 주저하는 경우가 많다. 이러한 완전무치악 환자들의 경우에는 치료에 들어가기에 앞서, 내원의 횟수를 줄이면서, 새 의치에 대한 적응기간도 줄일 수 있는 치료목표 또한 함께 고려해야 할 필요성이 있다. 본 증례는 신체적 능력이 저하된 고령의 완전무치악 환자의 총의치 제작 증례로서, Sato가 제시한 예비 및 정밀 폐구기능인상을 통해 흡착식 의치를 제작함과 동시에, CAD/CAM을 활용하여 기존의치의 교합적 기능정보를 이전함으로써 새 의치에 대한 적응을 용이하도록 하였다.