• Bulletin of the Korean Mathematical Society
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• v.57 no.2
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• pp.449-457
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• 2020

The aim of this short paper is to show some rigidity results for the actions of certain finitely presented groups by homeomorphisms. As an interesting and special case, we show that the actions of Higman-Thompson groups by homeomorphisms on a cohomology manifold with a non-zero Euler characteristic should be trivial. This is related to the wellknown Zimmer program and shows that the actions by homeomorphism could be very much different from those by diffeomorphisms.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.4
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• pp.295-300
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• 2011

Introduction: Hydroxyapatite(HA) coating implant can accelerate osseointegration, however, there are many controversies. Materials and Methods: This study examined the early osseointegration of two types of hydroxyapatite coated implants. Twelve adult male miniature pigs (Medi Kinetics Micropigs, Medi Kinetics Co., Ltd., Busan, Korea) were used in this study. In the implants placed in the mandible, a histomorphometric evaluation was performed to evaluate the bone-implant contact (BIC) ratio. Results: The BIC ratio increased with time. TS III HA and Zimmer HA were not significantly different (P>0.05). At 8 weeks, the BIC of Zimmer HA was higher than TS III HA, but there was no significant difference (P>0.05). Conclusion: HA coated implants will accelerate early osseointegration.

• Imaging Science in Dentistry
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• v.53 no.4
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• pp.335-344
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• 2023

Purpose: This bibliometric analysis aimed to provide a comprehensive overview of the characteristics, trends, and level of diagnostic efficacy of studies on cone-beam computed tomography (CBCT) published in Imaging Science in Dentistry (ISD) from 2011 to 2022. Materials and Methods: Publications related to CBCT identified in the electronic collection of ISD were selected according to eligibility criteria by 2 independent reviewers who collected data on the characteristics of the articles (year, authors, and country). The type and topic of studies were analyzed using VOSviewer v.1.6.18 (Centre for Science and Technology Studies, Leiden University, Leiden, Netherlands). The research articles were classified according to the hierarchical scale of diagnostic efficacy. Results: Of the 236 articles included, most were from South Korea and Brazil. Bong-Hae Cho and Yun-Hoa Jung were the most prolific authors on the topic of CBCT. The most frequently published types of studies were cross-sectional and laboratory-based. The most popular topics WERE related to the diagnosis of pathologies and/or alterations, as well as anatomical variations. On the diagnostic efficacy scale, most studies were rated level 1 (technical efficacy) or 2 (diagnostic accuracy efficacy). Conclusion: A steady increase was observed in publications related to CBCT, which are of both clinical and academic interest. The trends in these publications were analyzed, revealing that most are cross-sectional studies primarily exploring the capabilities of CBCT in diagnosing pathologies and/or changes in the oral and maxillofacial complex. These studies were typically classified as level 1 or 2 on the diagnostic efficacy scale.