• Journal of Periodontal and Implant Science
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• v.32 no.4
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• pp.711-719
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• 2002

Background : Terminology is a good index of reflections in conceptional imaginations, trends and technological advances in the field of their own. The purpose of this study is to compare the similarity and difference of terms in periodontology to evaluate the communicability between South and North Korea. These result may be particularly helpful for making glossary, academic communication and social unity at the time of reunion. Methods : This study was carried out by searching northern periodontology terminologies used in literatures published in North Korea and comparing those terms with the southern terms. The standard northen terms were not able to be distinguished, so the terms used frequently were chosen as the standard northern terms. Results : The South and North both use terms that stem from Chinese characters, but this tendency is stronger in the South. The main differences between the South and North are due to the North Korea's effort in converting terms into the native languages. There are also some differences in inscription of foreign language, spelling and spacing, and so on. Conclusion : The terminology using in South and North Korea in the field of periodontology is somewhat different but both side can be capable of communication. Now the basic efforts in both parts must be taken, such as establishing new terms, in order to relieve these differences.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.273-298
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• 2008

Purpose: The aim of this review is to introduce a novel bone-graft material for hard-tissue regeneration based on the calcium phosphate glass(CPG). Materials and Methods: CPG was synthesized by melting and subsequent quenching process in the system of CaO-$CaF_2-P_2O_5$-MgO-ZnO having a much lower Ca/P ratio than that of conventional calcium phosphates such as HA or TCP. The biodegradability and bioactivity were performed. Effects on the proliferation, calcification and mineralization of osteoblast-like cells were examined in vitro. Influence in new bone and cementum formations was investigated in vivo using calvarial defects of Sprague-Dawley rats as well as 1-wall intrabony defect of beagle dogs. The application to the tissue-engineered macroporous scaffold and in vitro and in vivo tests was explored. Results: The extent of dissolution decreased with increasing Ca/P ratio. Exposure to either simulated body fluid or fetal bovine serum caused precipitation on the surface. The calcification and mineralization of osteoblast-like cells were enhanced by CPG. CPG promoted new bone and cementum formation in the calvarial defect of Sprague-Dawley rats after 8 weeks. The macroporous scaffolds can be fabricated with $500{\sim}800{\mu}m$ of pore size and a three-dimensionally interconnected open pore system. The stem cells were seeded continuously proliferated in CPG scaffold. Extracellular matrix and the osteocalcin were observed at the $2^{nd}$ days and $4^{th}$ week. A significant difference in new bone and cementum formations was observed in vivo (p<0.05). Conclusion: The novel calcium phosphate glass may play an integral role as potential biomaterial for regeneration of new bone and cementum.

• Clinics in Shoulder and Elbow
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• v.22 no.1
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• pp.16-23
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• 2019

Background: We aimed to evaluate whether the use of our novel patient-specific guide (PSG) with 3-dimensional reconstruction in reverse total shoulder arthroplasty (RTSA) would allow accurate and reliable implantation of the glenoid and humeral components. Methods: 20 fresh-frozen cadaveric shoulders were used. The PSG group (n=10) and conventional group (n=10) was evaluated the accuracy and reproducibility of implant positioning between before and after surgery on the computed tomography image. Results: The superoinferior and anteroposterior offset in the glenoid component were $0.42{\pm}0.07$, $0.50{\pm}0.08$ in the conventional group and $0.45{\pm}0.03$, $0.46{\pm}0.02$ in the PSG group. The inclination and version angles were $-1.93^{\circ}{\pm}4.31^{\circ}$, $2.27^{\circ}{\pm}5.91^{\circ}$ and $0.46^{\circ}{\pm}0.02^{\circ}$, $3.38^{\circ}{\pm}2.79^{\circ}$. The standard deviation showed a smaller difference in the PSG group. The anteroposterior and lateromedial humeral canal center offset in the humeral component were $0.45{\pm}0.12$, $0.48{\pm}0.15$ in the conventional group and $0.46{\pm}0.59$ (p=0.794), $0.46{\pm}0.06$ (p=0.702) in the PSG group. The PSG showed significantly better humeral stem alignment. Conclusions: The use of PSGs with 3-dimensional reconstruction reduces variabilities in glenoid and humerus component positions and prevents extreme positioning errors in RTSA.

• Journal of Periodontal and Implant Science
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• v.53 no.1
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• pp.20-37
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• 2023

Purpose: Our pilot study showed that a 3-dimensional dual drug delivery scaffold (DDDS) loaded with Chinese herbs significantly increased the regenerated bone volume fraction. This study aimed to confirm the synergistic anti-inflammatory and osteogenic preclinical effects of this system. Methods: The targets and pathways of parthenolide and naringin were predicted. Three cell models were used to assess the anti-inflammatory effects of parthenolide and the osteogenic effects of naringin. First, the distance between the cementoenamel junction and alveolar bone crest (CEJ-ABC) and the bone mineral density (BMD) of surgical defects were measured in a rat model of periodontitis with periodontal fenestration defects. Additionally, the mRNA expression levels of matrix metallopeptidase 9 (MMP9) and alkaline phosphatase (ALP) were measured. Furthermore, the number of inflammatory cells and osteoclasts, as well as the protein expression levels of tumor necrosis factor-alpha (TNF-α) and levels of ALP were determined. Results: Target prediction suggested prostaglandin peroxidase synthase (PTGS2) as a potential target of parthenolide, while cytochrome P450 family 19 subfamily A1 (CYP19A1) and taste 2 receptor member 31 (TAS2R31) were potential targets of naringin. Parthenolide mainly targeted inflammation-related pathways, while naringin participated in steroid hormone synthesis and taste transduction. In vitro experiments revealed significant antiinflammatory effects of parthenolide on RAW264.7 cells, and significant osteogenic effects of naringin on bone marrow mesenchymal stem cells and MC3T3-E1 cells. DDDS loaded with parthenolide and naringin decreased the CEJ-ABC distance and increased BMD and ALP levels in a time-dependent manner. Inflammation was significantly alleviated after 14 days of DDDS treatment. Additionally, after 56 days, the DDDS group exhibited the highest BMD and ALP levels. Conclusions: DDDS loaded with parthenolide and naringin in a rat model achieved significant synergistic anti-inflammatory and osteogenic effects, providing powerful preclinical evidence.