https://ir.ymlib.yonsei.ac.kr/handle/22282913/169007 2026-04-18T06:11:11Z 2026-04-18T06:11:11Z Dai, Xinning Huang, Xiaoqiong Deng, Xinwen Ye, Zhiqian Liu, Zixiang Li, Weiran Li, Yan Wu, Shuyi Li, Shujin https://ir.ymlib.yonsei.ac.kr/handle/22282913/211875 2026-04-14T07:26:06Z 2026-06-01T00:00:00Z

Title: Establishment of standardized intraoral implant model in the rabbit edentulous diastema Authors: Dai, Xinning; Huang, Xiaoqiong; Deng, Xinwen; Ye, Zhiqian; Liu, Zixiang; Li, Weiran; Li, Yan; Wu, Shuyi; Li, Shujin Abstract: Rabbits have been valued for decades as a model for osseointegration research and biomaterial evaluation, owing to the practical handling, ethical acceptance, and cost-effectiveness. The rabbit model provides an optimal compromise between clinical translatability and practical experimental viability when compared to both large-animal and rodent alternatives. However, rabbit models face inconsistencies across implant site selection criteria, implant geometric configurations, and operative techniques, underscoring the urgent need for standardized experimental frameworks to improve cross-study comparability. The edentulous diastema in rabbit mandible-an anatomical edentulous zone between incisors and premolars-is recognized as a promising intraoral site for implant placement due to its enhanced trabecular bone density and superior volumetric capacity. In contrast to commonly used extragnathic sites (e.g., tibia, femur), which lack a relevant oral microenvironment, the mandibular diastema offers both close anatomical analogy to the human jaw and straightforward surgical access. Herein, we identified an anatomically optimal implant site in rabbit mandibular edentulous diastema utilizing micro-CT-based quantitative analyses and designed a customized implant according to the measured value. Subsequently, we developed a standardized operative workflow for implant placement, and evaluated the osseointegration following 4 weeks and 12 weeks of implantation. Furthermore, we confirmed the applicability of the standardized rabbit intraoral implant model for peri-implantitis modeling. Collectively, we established a workflow for standardizing an intraoral implant model in the edentulous diastema of rabbits which provide highly reproducible, economical, and effective platform for fundamental inquiries into osseointegration, the evaluation of novel implant surface coatings, and the initial screening of biomaterials.

2026-06-01T00:00:00Z Mangal, Utkarsh Jinn, Hyeonseok Hyun, Chang Min Kim, Harim Cha, Jung Yul Lee, Kee-Joon Choi, Sung-Hwan 만갈 웃커시 https://ir.ymlib.yonsei.ac.kr/handle/22282913/211531 2026-03-26T05:07:06Z 2026-05-01T00:00:00Z

Title: Facial surface tracing approach to reduce the observation errors in 3D curvilinear landmark annotations on cone-beam computed tomography images Authors: Mangal, Utkarsh; Jinn, Hyeonseok; Hyun, Chang Min; Kim, Harim; Cha, Jung Yul; Lee, Kee-Joon; Choi, Sung-Hwan; 만갈 웃커시 Abstract: Objectives: To propose and validate a 3D facial surface tracing (3D-FAST) algorithm as a robust tracing method to reduce observation errors in identifying maxillofacial curvilinear landmarks. Methods: The 3D-FAST algorithm comprises four sequential steps: (1) extraction of bone structures from cone-beam computed tomography (CBCT) volumes utilizing Otsu's thresholding method; (2) conversion of segmented volumetric data into a mesh representation through the marching-cubes algorithm; (3) initial landmark identification employing a data-driven approach, followed by selective manual refinement; and (4) optimization of landmark positions by identifying maximal or minimal points within defined curvilinear regions. The algorithm's efficiency was validated using 55 CBCT datasets, with particular emphasis on the Orbitale landmark. Annotation efficiency was assessed by comparing landmark deviations, dihedral angles between reference planes, and asymmetry measurements with independent manually annotated datasets. Results: Compared to orthodontically trained CBCT users, 3D-FAST demonstrated the highest consistency with the centroid derived from user annotations. In constructing horizontal and vertical reference planes and conducting asymmetry analyses, reference planes generated by 3D-FAST showed significantly improved dihedral angle variation and asymmetry than those generated by an experienced CBCT human observer, the most consistent and experienced manual user. In addition, 3D-FAST achieved improved consistency when bilateral Orbitale landmarks were used for reference plane construction, compared to when unilateral Orbitale landmarks were used. Conclusions: 3D-FAST is a reliable method for annotating curvilinear landmarks in CBCT images. Clinical significance: 3D-FAST has the potential to enhance clinical workflows and outcomes by reducing the learning curve, minimizing subjectivity, and saving time.

2026-05-01T00:00:00Z Lee, Kar Wai Alvin Sydorchuk, Olena Song, Jong Keun Lee, Han Earl Livanskaya, Alyona Namthongton, Nil Wardhani, Putri Hendria Putri, Ardhiah Iswanda Yi, Kyu-Ho 이규호 https://ir.ymlib.yonsei.ac.kr/handle/22282913/211876 2026-04-14T07:26:58Z 2026-05-01T00:00:00Z

Title: Ideal Sized Chitosan (Arche) as a multifunctional biomaterial in aesthetic treatment Authors: Lee, Kar Wai Alvin; Sydorchuk, Olena; Song, Jong Keun; Lee, Han Earl; Livanskaya, Alyona; Namthongton, Nil; Wardhani, Putri Hendria; Putri, Ardhiah Iswanda; Yi, Kyu-Ho; 이규호 Abstract: Background: Aesthetic procedures such as laser resurfacing, microneedling, and injectable treatments intentionally disrupt the skin barrier, increasing susceptibility to microbial colonization, inflammation, and delayed healing. Post-procedural care therefore requires biomaterials that provide antimicrobial protection while supporting controlled inflammation and tissue regeneration. Observation: Chitosan, a naturally derived polysaccharide, exhibits unique combination of antimicrobial activity, immunomodulatory effects, and wound-healing support. These properties are influenced by molecular weight, degree of deacetylation, and formulation, allowing chitosan to function as a barrier material, bioactive dressing, and drug-delivery platform in aesthetic settings. Due to its ultra-low molecular weight (below 600 Da), Ideal Size Chitosan (ISC) manufactured by Arche (Doum Inc., Korea) is topically effective, as it can penetrate the skin barrier to target deeper dermal layers and deliver enhanced bioactive effects. Clinical relevance: In post-aesthetic care, chitosan-based films, hydrogels, and nanoparticles may reduce infection risk, modulate excessive inflammatory responses, and promote re-epithelialization. However, variability among chitosan formulations and limited procedure-specific clinical data remain important considerations. Conclusion: This short communication highlights the rationale for using chitosan as a multifunctional biomaterial in aesthetic aftercare and underscores the need for standardized formulations and targeted clinical studies. (c) 2026 The Authors. Published by Elsevier Ltd on behalf of British Association of Plastic, Reconstructive and Aesthetic Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

2026-05-01T00:00:00Z Choi, Eun-Hack Andrew Shin, Yunji Yu, Jae-Hun Kim, Jeenyoung Mangal, Utkarsh Kim, Jun-Young Choi, Sung-Hwan 만갈웃커시 https://ir.ymlib.yonsei.ac.kr/handle/22282913/211534 2026-03-27T02:17:29Z 2026-04-01T00:00:00Z

Title: Clinical acceptability and repeatability of three-dimensional maxillary positioning following orthognathic surgical wafer placement: An in vitro study Authors: Choi, Eun-Hack Andrew; Shin, Yunji; Yu, Jae-Hun; Kim, Jeenyoung; Mangal, Utkarsh; Kim, Jun-Young; Choi, Sung-Hwan; 만갈웃커시 Abstract: Objectives: To quantify the three-dimensional (3D) deviation between planned and achieved maxillary positions after transfer using a surgical wafer under in vitro conditions, and assess clinical acceptability and repeatability for each workflow. Methods: A bracketed typodont mounted on a mannequin was used to define three groups-Conventional (alginate impressions/plaster casts/laboratory scanning), Trios (Trios 3 intraoral scanner (IOS)), and Prime (Primescan IOS)-each with 10 technical replicates. For each replicate, virtual surgical planning was performed, a wafer was designed and 3D-printed, and the maxilla was positioned; 3D deviation was quantified as: (1) point-based 3D positional deviation (three landmarks) and (2) matrix-based 3D translational and rotational deviations. Clinical acceptability was defined as the proportion of the 10 replicates per group with 3D deviation within predefined clinical tolerance limits (0.5 mm for positional/translational; 1.0 degrees for rotational). Repeatability was summarized by the repeatability standard deviation (sr) as specified in ISO 5725. Results: The Trios and Prime groups achieved 100% clinical acceptability across all 3D deviations. In the Conventional group, acceptability was 90% for the anterior landmark's positional and translational deviation, with all others achieving 100%. The sr was 0.13-0.20 mm (positional), 0.23 mm (translational), and 0.22 degrees (rotational) for the Conventional group; 0.04-0.13 mm, 0.06 mm, and 0.24 degrees for the Trios group; 0.04-0.10 mm, 0.11 mm, and 0.17 degrees for the Prime group. Conclusion: Under in vitro conditions, the demonstrated clinical acceptability and repeatability provide preliminary evidence supporting the clinical feasibility of a fully digital IOS-based workflow for wafer-mediated maxillary positioning. Clinical significance: An IOS-based workflow can be considered clinically feasible for wafer-mediated maxillary positioning without compromising accuracy, as evaluated in terms of clinical acceptability and repeatability, while potentially eliminating impression-taking and cast fabrication steps.

2026-04-01T00:00:00Z