• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.425-431
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• 2018

Composite particles of porous silica and cerium oxide nanoparticles blocking UV/blue light were prepared through a dry coating process. Various composite particles were prepared by varying conditions such as the mixing ratio of cerium oxide and silica, and the chamber rotating speed of mechano fusion system. The surface morphology of the composite particles was observed with SEM and the composition was analyzed using X-ray fluorescence (XRF). When the cerium oxide/silica composite particles were dispersed in water, the transparency and dispersion stability of the colloidal solution were improved. In addition, the fluidity and spreadability of the particle powder were enhanced by making composite particles. These results show that cerium oxide/silica composite particles can be used as functional cosmetic ingredients for UV/blue light protection.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.586-592
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• 2022

In this study cerium nano particles(CNPs) with 0-4.0 wt% was incorporated to the conventional dental pit and fissure sealant(ConciseTM) to produce new pit and fissure sealant the physical properties and cytotoxicity. The physical properties were measured for polymerizing depth the degree of water absorption and solubility. The cytotoxicity of cell viability was analyzed by MTT assay using immortalized human oral keratinocyte(IHOK). As a result of this preceding study the polymerizing depth was decreased by the increasing of the amount of CNPs. The solubility degree of the sealant added CNPs with 2.0 wt% showed was the lower and the water absorption showed no significantly difference with the control groups(p>0.05). The cytotoxicity test results showed high survival rates in all experimental groups. Therefore, pit and fissure sealant by the addition of CNPs excellent cell viability be produced without weaken the physical property of the cell viability fissure sealant containing CNPs does not weaken physical properties and has no cytotoxic effects biocompatibility. Considering its properties effect of CNPs, further studies are required for distribution technology application.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.433-438
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• 2020

The aim of this study was to investigate the mechanical properties of pit and fissure sealant containing cerium oxide nano particles(CNP). Used to mix with pit and fissure sealant (Concise^TM, USA). CNP was added into liquid (0- 4.0 wt%) of pit and fissure sealant. The specimens for the vickers hardness (VHN; 10 × 2 mm), Three-point flexure (FS; 2 × 2 × 25 mm) with flexure modulus (FM) were obtained from cements at 1, 7, and 14 days after storing in (37±1)℃ distilled water. All mechanical strength tests were conducted using machine (Instron 3344) with a cross-head speed of 1 mm/min. Data were statistically analyzed by one-way ANOVA and Duncan posthoc test(p<0.05). Mechanical properties of conventional pit and fissure sealant could be enhanced by addition of CNP. Three-point flexure and modulus of pit and fissure sealant containing CNP were showed a slightly higher value not significantly with the group(p>0.05). The vickers hardness values were increase significantly with incubation time(p<0.05). Results indicated that CNP can be used considered as potential reinforcing agent for increasing mechanical properties for conventional pit and fissure sealant. Therefore, it was suggest that the additional effects of CNP and research on a wide range of substances.

• Journal of Korean society of Dental Hygiene
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• v.20 no.4
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• pp.535-543
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• 2020

Objectives: The aim of this study was to investigated the surface roughness and change in the amount of adhesion of Streptococcus mutans to the commercial pit and fissure sealant containing cerium oxide nano particles(CNPs). Methods: The CNPs was incorporated into a commercial pit and fissure sealant at 0-4.0 wt%. Disk Specimens (ϕ 10 mm × 2 mm) were prepared by light polymerization the front and back for 40s. Average surface roughness was measured and Streptococcus mutans adhesion was observed under confocal laser scanning microscopy (CLSM) after 24 hour. Data were statistically analyzed by one-way ANOVA and Tukey HSD^a post-hoc test. Results: Difference of the surface roughness(Ra) between groups was not statistically significant in both non CNPs group and CNPs group(p>0.05). In CNPs group, the amount of S. mutans adhesion was significantly different between control group and decreased in order of CNPs 4.0, CNPs 0.5, CNPs 1.0 and CNPs 2.0(p<0.05). Conclusions: Within the limitation of this study, these aspects of oral bacteria performances suggest potential usefulness of the CNPs incorporation, especially CNPs 1% and 2%, in pit and fissure sealant for inducing antibacterial effect.