• Journal of the Korean Ceramic Society
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• v.39 no.5
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• pp.467-472
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• 2002

Long Carbon Nanotubes(CNTs) were cut by diamond lapping film followed by observation using SEM. The paste was prepared by mixing shortened CNT powder, ${\alpha}$-terpineol used as a solvent, and ethylcellulose as a binder. This paste was deposited on glass substrate by screen printing and extruded by syringe. After screen printing, several post-treatments were performed to control the alignment of CNTs perpendicular to the substrate. The deposited CNTs were scratched by sand paper or diamond lapping film. It was also treated by attachment followed by an immediate detachment using the adhesive tape. SEM observation indicates that excellent vertical alignment of CNTs could be achieved by simple post-treatments from the screen printed-CNTs paste. Similar alignment of CNTs is also observed in the as-extruded CNTs paste.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.4
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• pp.293-298
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• 2017

In this study, we developed a 3D chocolate printer and studied the conditions needed for chocolate printing. Because chocolate is a mixture of cocoa mass, cocoa butter and sugar particles, its properties vary with temperature, and care is required in melting and extrusion. A chocolate supply unit is composed of a heating block and a syringe pump. It is integrated with a 3-axis linear robot. In order to be more accurate than the existing 3D chocolate printer is, the system was configured so that the printing line width became $430{\mu}m$. Printing performance was studied according to various parameters. The condition needed for printing lines with a stable width was discovered by the experimental design method and has been confirmed by a 2D line test. These 3D printing experiments showed that it was possible to build a 3D shape with an inclination angle of up to $45^{\circ}$ without support. Further, chocolate printing of a 3D shape has been successfully verified with the developed system.

• Restorative Dentistry and Endodontics
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• v.47 no.1
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• pp.11.1-11.11
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• 2022

This study aimed to describe the outcomes of the GentleWave system (GW) (Sonendo) on root canal treatment. Published articles were collected from scientific databases (MEDLINE/PubMed platform, Web of Science, Scopus, Science Direct and Embase). A total of 24 studies were collected from August/2014 to July/2021, 20 in vitro and 4 clinical. GW System was not associated with extrusion of the irrigant, promoted faster organic dissolution than conventional syringe irrigation (CSI), passive ultrasonic irrigation (PUI) continuous ultrasonic irrigation (CUI) and EndoVac, reduced more bacterial DNA and biofilm than PUI and CUI, promoted higher penetration of sodium hypochlorite into dentinal tubules than PUI and CUI in vitro, and removed more intracanal medication than CSI and PUI. GW was able to remove pulp tissue and calcifications. Moreover, its ability to remove hard-tissue debris and smear layer was better than that of CSI, and its ability to remove root canal obturation residues was lower or similar to that of PUI, and similar to that of CSI and EndoVac. Regarding root canal obturation of minimally instrumented molar canals, GW was associated with high-quality obturation. Clinically, the success rate of endodontic treatment using GW was 97.3%, and the short-term postoperative pain in the GW group was not different from CSI. Further research, mainly clinical, is needed to establish whether GW has any advantages over other available irrigation methods.