YONSEI UNIVERSITY COLLEGE OF DENTISTRY e-Newsletter 2023-4 / December

Yonsei University College of Dentistry Secures Top Rank for Second Consecutive Year in Global Rankings

Yonsei University College of Dentistry (YUCD) ranked 1st in Korea and 43rd in the world in the clinical and health subject, according to the THE (Times Higher Education) World University Rankings 2024. It was the second straight year that YUCD topped the rankings in Korea.

The THE World University Rankings for clinical and health subject uses five methodologies with different weightings that are combined to produce the final result: ▲ Teaching: the learning environment (26.8%), ▲ Research environment: volume, income, and reputation (26.5%), ▲ Research quality: strength, influence, and excellence (35.2%), ▲ International outlook: staff, students, and research (7.5%), ▲ Industry: income and patents (4%).

Among these, the score for Research Quality has notably increased compared to last year. Yonsei University College of Dentistry has been dedicated to increasing research capabilities by conducting various projects in collaboration with globally renowned research centers. Moreover, YUCD operates the Young Eagle Program, allowing undergraduate students to participate in basic science research work, and offers AI advanced courses to prepare for the latest developments in digital dentistry.

Meanwhile, YUCD ranked 1st in Korea and 28th in the world according to the 2023 QS World University Rankings for Dentistry.

Yonsei International Dental Academy Proclaims the First International Education Institution for Dentist

The Continuing Education Center at Yonsei University College of Dentistry has officially transitioned to the Yonsei International Dental Academy (YIDA) and celebrated the unveiling of its new signboard. In 2023, the academy has expanded its course offerings for foreign participants, doubling the number compared to those available for domestic participants. YIDA now offers an increased count of international courses, totaling twenty in the year 2023 alone.

YIDA stands as the very first dental education institution in Korea dedicated to educating dentists on a global scale. This achievement owes much to our faculty members, who have made significant effort in developing and conducting these international courses. With its growing global recognition, YIDA aims to establish itself as a dependable and esteemed dental academy for dentists worldwide.

Dr. McAnlis Heritage Gifting Ceremony in Celebration of 100 Years of Korean Dental Specialties

On December 4th, the 'Dr. McAnlis Heritage Gifting Ceremony in Celebration of 100 Years of Korean Dental Specialties' was held at Yonsei University. This commemorated a century of specialized dental treatments, including Orthodontics, Oral Surgery, Oral Radiology, and Pediatric Dentistry, which began in Korea in 1923.

Mr. Montgomery McAnlis, the great-grandson of late Dr. J. A. McAnlis, an American missionary dentist who served as the third director of the Severance Dental Clinic, donated Dr. McAnlis' heritage, which included his bible and valuable photobooks, adding significance to the event.

During the ceremony, Professor Junhewk Kim shared the results of his study, which focused on 35 Korean dentists pivotal to the history of Yonsei dentistry. These professionals were either trained or had worked at the Severance Dental Hospital, initiating specialized treatments as early as 1923. The unwavering dedication of these pioneers forms the foundation of Korean dental science, remaining a cornerstone in the rich legacy and ongoing advancements within the field today.

Paradigm Shifter: Yonsei University College of Dentistry Designated as a Training Institute for RA Specialist

The National Institute of Medical Device Safety Information (NIDS) has appointed Yonsei University College of Dentistry as a training institute for Regulatory Affairs (RA) specialists in medical devices. Commencing in 2024, YUCD will administer an educational curriculum encompassing premarket approval, good manufacturing practices (GMP), post-management, and overseas licensing. Graduates completing these courses and obtaining an RA license will have a defined career path within the medical devices field.

YUCD stands as the exclusive RA training institute within the domain of dental science in Korea. This distinction is particularly notable due to the establishment of the Department of Industrial Dentistry in 2023. The RA specialist training curriculum aligns seamlessly with that of the Department of Industrial Dentistry, enabling comprehensive training for students. This endeavor is anticipated to significantly contribute to the advancement of dental medical devices, which is pivotal in enhancing dental treatments.

Yonsei University College of Dentistry Receives Generous Donations from Alumni

The Yonsei University College of Dentistry recently received substantial donations from esteemed alumni, showcasing a profound dedication to their alma mater's legacy. Dr. Young-Joon Kim, a graduate of the 11th cohort, and Dr. Joong-ki Lim from the 19th cohort each donated $80,000, driven by a shared desire to honor the institution that shaped their careers. Dr. Kim emphasized how YUCD had been instrumental in motivating his work as a dentist in Korean society, while Dr. Lim aspired to cultivate a culture of giving among fellow alumni.

Adding to this support, Professor Sung-Hwan Choi from the 35th cohort contributed $15,000—an award received as the winner of the prestigious MINEC Academic Award. Thanks to their generous donations, we've solidified the enduring bond between the institution and its graduates, fostering a strong sense of unity within the YUCD community.

Exploring Future Frontiers: 22nd Yonsei Dental International Symposium

The 22nd Yonsei Dental International Symposium took place on December 8, 2023, featuring two sessions: an Academic Poster Presentation and the 8th Joint Symposium of the College of Dentistry & College of Engineering.

During the poster presentation session, 108 students and researchers participated, sharing their research achievements and clinical case reviews. The significant increase in the number of participants compared to past years reflects the growing impact of the symposium. Among them, 16 individuals were recognized for delivering the best presentations based on the criteria of creativity and the relevance of their research.

Later in the day, the College of Dentistry and the College of Engineering hosted a joint symposium themed 'Dental & Engineering Synergy-Advancing Innovation.' This session highlighted the collaborative research achievements in Artificial Intelligence between the two colleges. Additionally, cutting-edge technologies like exhaled breath analysis equipment and lenseless computational cameras for smart imaging were introduced. This symposium demonstrated that the convergence of science and medicine holds vast future possibilities for modern dentistry.

1. Occlusive membranes for guided regeneration of inflamed tissue defects

Guided bone regeneration (GBR) is a technique employed in dental procedures, like implant placement, with help of a barrier membrane to facilitate bone growth by supporting the proliferation and differentiation of osteoblasts, the bone-forming cells. However, these membranes often face contamination from oral microorganisms, which can impede periodontal regeneration. Addressing this challenge, a team from Yonsei University College of Dentistry, led by Professor Sung-Hwan Choi (Department of Orthodontic Science) and Professor Jae-Kook Cha (Department of Periodontology), with post-doctoral research fellow Dr. Utkarsh Mangal (Department of Orthodontics), developed an innovative membrane. This novel membrane, enriched with high-density hydroxyapatite, is known as the Symbiotically Integrating Occlusive Membrane (SIOM). Drawing inspiration from the protective qualities of natural enamel, SIOM effectively guards against microbial contamination, representing a significant advancement in dental biomaterials.

Their research showcased that SIOM facilitated the simultaneous regeneration of gingiva (gums) and alveolar bone in severely infected oral tissues. Notably, it also promoted the growth of only beneficial microorganisms from human saliva. The effectiveness of the membrane in regenerating both soft and hard tissues was confirmed through in vivo animal experiments. The study also underscored the importance of maintaining a healthy microbial environment for successful human tissue regeneration. Published in 'Nature Communications' (Impact Factor of 16.6; JCR: top 7.5%), in November 2023, this research marks a significant breakthrough in the field of biomaterials for effective and safe dental tissue regeneration.

Utkarsh Mangal: Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry

Jae-Kook Cha: Department of Periodontology, Research Institute for Periodontal Regeneration, Yonsei University College of Dentistry

Sung-Hwan Choi: Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry

Abstract

Guided bone regeneration aided by the application of occlusive membranes is a promising therapy for diverse inflammatory periodontal diseases. Symbiosis, homeostasis between the host microbiome and cells, occurs in the oral environment under normal, but not pathologic, conditions. Here, we develop a symbiotically integrating occlusive membrane by mimicking the tooth enamel growth or multiple nucleation biomineralization processes. We perform human saliva and in vivo canine experiments to confirm that the symbiotically integrating occlusive membrane induces a symbiotic healing environment. Moreover, we show that the membrane exhibits tractability and enzymatic stability, maintaining the healing space during the entire guided bone regeneration therapy period. We apply the symbiotically integrating occlusive membrane to treat inflammatory-challenged cases in vivo, namely, the open and closed healing of canine premolars with severe periodontitis. We find that the membrane promotes symbiosis, prevents negative inflammatory responses, and improves cellular integration. Finally, we show that guided bone regeneration therapy with the symbiotically integrating occlusive membrane achieves fast healing of gingival soft tissue and alveolar bone.

Multiple nucleation biomineralization scheme for development of enamel inspired Symbiotically Integrating Occlusive Membrane (SIOM)
Summary of the study

2. Lipid anchor-mediated NK cell surface engineering for enhanced cancer immunotherapy

Currently, the therapeutic impact of natural killer (NK) cell-based immunotherapy on solid tumors, particularly triple-negative breast cancer, is hindered by insufficient cancer recognition specificity. To overcome the limitations of cell-based immunotherapy on solid cancer, Professor Jung's team focused on surface engineering technology in NK cells. They developed artificial lipid-folate conjugates, for stable anchoring onto NK cell surfaces via hydrophobic interactions, thus augmenting folate-mediated ligand-receptor immune interactions with target cancers. It improved the cancer recognition and tumor-infiltration of surface-engineered NK cells, and suppressed the tumor progression and metastasis was confirmed in the triple-negative breast cancer model. According to the current research findings, we have presented fundamental evidence supporting the idea that surface modification technology can effectively improve the cancer recognition and tumor-targeting capabilities of cell therapy products. This suggests the potential for a novel approach in the development of methods for treating solid cancers. This study was published in the international scientific journal 'Chemical Engineering Journal' (Impact Factor 15.1) in October 2023.

Division in Anatomy and Developmental Biology, Department of Oral Biology, Yonsei University College of Dentistry

Abstract

Current natural killer (NK) cell-based cancer immunotherapy for the treatment of solid tumors often exhibits insufficient cancer recognition specificity, thereby limiting therapeutic anticancer efficacy, especially for triple-negative breast cancers (TNBCs). In this study, we develop artificial lipid-folate conjugates, for stable anchoring onto NK cell surfaces via hydrophobic interactions, thus augmenting folate-mediated ligand-receptor immune interactions with target cancers. This hydrophobized conjugate anchor provides additional cancer recognition ligands without any sophisticated genetic modification, and successfully enhances the anticancer efficacies of surface-coated NK (SCNK) cells without disturbing their intrinsic properties. Augmented cancer recognition ability sequentially promotes the secretion of cytolytic granules (granzyme and perforin) with cytokine (TNF-α), demonstrating improved cytotoxicity of the SCNK cells. Furthermore, the SCNK cells significantly infiltrate into the tumor site, inducing tumor apoptosis/necrosis, and suppressing tumor progression and metastasis in TNBC mouse models. Taken together, our artificial lipid-folate conjugates enable the treatment of solid tumors by augmenting the cancer-recognition and tumor targeting capacity of surface-engineered NK cells.

Summary of the study
Anti-cancer efficacy of surface-engineered NK cells in triple-negative breast cancer model

3. Effect of strontium substitution on functional activity of phosphate-based glass

Strontium plays a crucial role in regulating bone metabolism, being a key trace element in the human body. Due to its chemical properties, strontium enhances hard tissue regeneration and reduces inflammation. Phosphate-based glasses (PBG) are well-regarded in tissue regeneration for their modifiable degradation rates and solubility. To harness the benefits of strontium in PBG, a research team from Yonsei University College of Dentistry, including Professors Sung-Hwan Choi (Department of Orthodontics), Jae-Sung Kwon (Dental Biomaterials and Bioengineering), Jae-Kook Cha (Department of Periodontology), and post-doctoral fellows from Department of Orthodontics, Dr. Jeong-Hyun Ryu and Dr. Utkarsh Mangal, explored optimal parameters for maximum bioactive effects. Their research yielded significant results: a 6 mol% strontium-substituted phosphate-based glass, named PSr6, exhibited a stable network structure, promoted osteogenic differentiation, and diminished inflammatory responses. Furthermore, in vivo animal experiments showed that PSr6 outperformed traditional bioactive glass in compatibility and efficacy in new bone formation. Published in 'Biomaterials Science' (Impact Factor 6.6) in September 2023, this study positions PSr6 as a highly promising material for dental bone grafting applications, representing a notable advancement in biomaterials for dental health.

Jeong-Hyun Ryu: Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry

Utkarsh Mangal: Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry

Jae-Kook Cha: Department of Periodontology, Research Institute for Periodontal Regeneration, Yonsei University College of Dentistry

Jae-Sung Kwon: Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry

Sung-Hwan Choi: Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry

Abstract

Phosphate-based glass (PBG) is a bioactive agent, composed of a glass network with phosphate as the primary component and can be substituted with various therapeutic ions for functional enhancement. Strontium (Sr) has been shown to stimulate osteogenic activity and inhibit pro-inflammatory responses. Despite this potential, there are limited studies that focus on the proportion of Sr substituted and its impact on the functional activity of resulting Sr-substituted PBG (PSr). In this study, focusing on the cellular biological response we synthesized and investigated the functional activity of PSr by characterizing its properties and comparing the effect of Sr substitution on cellular bioactivity. Moreover, we benchmarked the optimal composition against 45S5 bioactive glass (BG). Our results showed that PSr groups exhibited a glass structure and phosphate network like that of PBG. The release of Sr and P was most stable for PSr6, which showed favorable cell viability. Furthermore, PSr6 elicited excellent early osteogenic marker expression and inhibition of pro-inflammatory cytokine expression, which was significant compared to BG. In addition, compared to BG, PSr6 had markedly higher expression of osteopontin in immunocytochemistry, higher ALP expression in osteogenic media, and denser alizarin red staining in vitro. We also observed a comparable in vivo regenerative response in a 4-week rabbit calvaria defect model. Therefore, based on the results of this study, PSr6 could be identified as the functionally optimized composition with the potential to be applied as a valuable bioactive component of existing biomaterials used for bone regeneration.

PSr6 showed a stable glass network, promotion of osteogenic differentiation, and inhibition of the pro-inflammatory response. As compared with benchmarked BG, PSr6 indicated the regenerative activity as new bone and had potential dental bone grafting materials
Summary of the study