• 대한소아치과학회지
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• 제51권2호
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• pp.132-139
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• 2024

This study aimed to compare the fluoride-releasing ability and degree of microbial attachment of a newly developed glass-hybrid restorative material (GH) with those of a high-viscosity glass ionomer (HvGIC), resin-modified glass ionomer (RMGI), and composite resin (CR). In addition, the correlation between fluoride-releasing ability and microbial attachment between materials was evaluated. Specimens were prepared in a disc shape and divided into 4 groups according to the materials (GH, HvGIC, RMGI, and CR). The fluoride release experiments were performed in each group (n = 15). The amount of fluoride released was measured on days 1, 3, 7, 14, 28, and 42 after storage. For the microbial attachment experiment, 12 specimens were produced per group using Mutans Streptococci (S.mutans ), a cariogenic microorganism. S. mutans was cultured on the specimens for 24 hours, and the number of bacteria was measured. GH had the highest cumulative fluoride release and showed a significant difference when compared with RMGI (p = 0.001) and CR (p < 0.0001). Microbial attachment was the lowest in GH; however, no significant difference was observed between the materials (p = 0.169). There was no significant correlation between fluoride release from materials and microbial attachment (p > 0.05). From this perspective, remineralization of low-mineralized areas could be expected due to the high fluoride release of GH, and the effect of delaying the progression of dental caries could be predicted from the low cariogenic microbial attachment. Therefore, GH might be a useful restorative material for treating immature permanent teeth with hypomineralized enamel. However, further studies are needed about the degree of remineralization of hypomineralized areas after restoration and the capacity to recharge fluoride.

• Restorative Dentistry and Endodontics
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• 제25권1호
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• pp.109-115
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• 2000

This study was designed to evaluate the microhardness of restorative composite resin and dual-cured composite resin cement which were light cured through the 1.5mm thickness composite overlay. For restorative materials, Z100 and Tetric Ceram were used. For dual cured composite cements, Variolink II((VL II) of three consistency (low, high, ultra high) were used. To determine the optimal microhardness of Z100, Tetric Ceram and Variolink II, each material was packed into the 1mm thickness teflon mold without composite overlay and light cured for 60 seconds. Then the microhardnesses of each sample were measured, averaged and regarded as optimal hardness of each material. To evaluate the microhardness of restorative composite resin and dual-cured composite resin cement which were light cured through the 1.5mm thickness composite overlay, the composites were packed into 1mm thickness teflon mold, coverd with celluloid strip, and then precured composite overlay which was made of Targis(Ivoclar/Vivadent, Liechtenstein) was positioned. 2 types of visible light curing machine, the power density of one of which was 400$mW/cm^2$ and the other was 900$mW/cm^2$, and one type of argon laser were used to cure the restorative composite and dual cured cement. For each group, 10 sample were assigned. The light curing tip was positioned over the composite overlay and light cured for 1min., 2min. or 3min with visible light curing machine or 15sec, 30 sec, 45sec, and 60 sec with argon laser. The Vickers hardnesses of upper and lower surface of Z100, Tetric Ceram, and 3 types of VL II cement were measured. When the 900 $mW/cm^2$ curing light was used, 2min. was needed for optimal curing of Z100 and Tetric Ceram. Variolink II did not be cured optimally even though the curing time was extended to 3min. When 400$mW/cm^2$ curing light was used, 3min. was necessary for Z100, whereas 3min. was not enough for Tetric Ceram. Variolink II was not cured optimally even though the curing time was extended to 3min. When argon laser was used, Z100, Tetric Ceram and Variolink II were not cured optimally in 60 seconds.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.21.1-21.12
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• 2021

Objectives: This study compared the cytotoxicity, biocompatibility, and tenascin immunolabeling of a new ready-to-use hydraulic sealer (Bio-C Sealer) with MTA-Fillapex and white MTA-Angelus. Materials and Methods: L929 fibroblasts were cultivated and exposed to undiluted and diluted material extracts. Polyethylene tubes with or without (the control) the materials were implanted into the dorsa of rats. At 7 days and 30 days, the rats were euthanized, and the specimens were prepared for analysis; inflammation and immunolabeling were measured, and statistical analysis was performed (p < 0.05). Results: MTA-Fillapex exhibited greater cytotoxicity than the other materials at all time points (p < 0.05). The undiluted Bio-C Sealer exhibited greater cytocompatibility at 6 and 48 hours than white MTA-Angelus, with higher cell viability than in the control (p < 0.05). White MTA-Angelus displayed higher cell viability than the control at 24 hours, and the one-half dilution displayed similar results at both 6 and 48 hours (p < 0.05). At 7 days and 30 days, the groups exhibited moderate inflammation with thick fibrous capsules and mild inflammation with thin fibrous capsules, respectively (p > 0.05). At 7 days, moderate to strong immunolabeling was observed (p > 0.05). After 30 days, the control and MTA-Fillapex groups exhibited strong immunolabeling, the white MTA-Angelus group exhibited moderate immunolabeling (p > 0.05), and the Bio-C Sealer group exhibited low-to-moderate immunolabeling, differing significantly from the control (p < 0.05). Conclusions: Bio-C Sealer and white MTA-Angelus exhibited greater cytocompatibility than MTA-Fillapex; all materials displayed adequate biocompatibility and induced tenascin immunolabeling.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 춘계 학술발표대회
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• pp.65-66
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• 2003

Korean ginseng (Panax ginseng C. A. Meyer) is an representative medicinal herb. It is classified as an adaptogen, helping the body to adapt to stress, improving stamina and concentration, and providing a normalizing and restorative effect. However, cultivation and breeding of the plant is very difficult because it requires at least 4-year cultivation from seed germination to root harvest.(중략)

• The Journal of Advanced Prosthodontics
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• 제10권1호
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• pp.50-57
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• 2018

PURPOSE. To investigate the effect of accelerated aging on surface properties of glazed CAD/CAM resin blocks using a 2D surface profilometer and a 3D non-contact optical profilometer. MATERIALS AND METHODS. Three types of CAD/CAM resin restorative materials, LAVA Ultimate (3M ESPE, St Paul, MN, USA), VITA Enamic (Vita Zahnfabrik H. Rauter, Bad $S\ddot{a}ckingen$, Germany), and Cerasmart (GC Corparation, Tokyo, Japan) were used for this study. CAD/CAM blocks were cut in 3-mm thickness slabs and divided into three groups; Group 1: control group (specimens polished with 600 grit SCI paper); Group 2: specimens sandblasted, silanized, and glazed with Optiglaze Color (GC); Group 3: glazed specimens subjected to 5000 thermocycles (n=15). The surface roughness ($R_a$ and $R_z$) was evaluated using a profilometer and a 3D scanning instrument. Data were analyzed using two-way ANOVA and Tukey's post- hoc test (P<.05). RESULTS. LAVA, VITA, and Cerasmart exhibited statistically similar $R_a$ and $R_z$ values for each group (P>.05). For VITA and Cerasmart, the specimens in Group 1 exhibited significantly higher $R_a$ values than Group 2 (P<.05). Group 1 ($0.502R_a$), Group 2 ($0.384R_a$), and Group 3 ($0.431R_a$) exhibited statistically similar $R_a$ values for LAVA (P=.062). After 5000 thermocycles, surface roughness values did not change significantly for glazed LAVA, VITA, and Cerasmart (P>.05). CONCLUSION. Glaze material Optiglaze Color makes CAD/CAM resin surfaces smooth and glazed CAD/CAM surfaces seem resistant to deterioration under 5000 thermocycles.

• 한국치위생학회지
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• 제13권2호
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• pp.351-360
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• 2013

Objectives : The purpose of this study was to evaluate the effects of tooth bleaching agent contained 15% carbamide peroxide on the color, microhardness and surface roughness of tooth-colored restorative materials by using pH cycling model. Methods : Four types of tooth-colored restorative materials, including a composite resin(Filtek Z350 ; Z350), a flowable composite resin(Filtek P60 : P60), a compomer(Dyract$^{(R)}$ AP ; DY), and a glass-ionomer cement(KetacTM Molar Easymix ; KM). were used in the study. Eighty-eight specimens of each material were fabricated, randomly divided into two groups(n=44): experimental group(15% carbamide peroxide) and control group(distilled water). These groups were then divided into four subgroups(n=11). All groups were bleached 4 hours per day for 14 days using pH cycling model. The authors measured the color, microhardness, and roughness of the specimens before and after bleaching. The data were analyzed with ANOVA and T-test. Results : Z350 and P60 showed a slight color change(${\Delta}E^*$), whereas DY and KM showed significantly color change(p<0.05). Among them, the greatest color change was observed in DY. Percentage microhardness loss(PML) of the distilled water group was 1.8 to 5.1%, and 15% peroxide peroxide group was 5.0 to 25.2%. Microhardness of DY and KM showed a statistically significant decrease(p<0.05). Roughness was increased in all groups after bleaching. Z350 and P60 does not have a significant difference(p>0.05), however DY and KM significantly increased more than the 0.2 ${\mu}m$(p<0.05). Conclusions : The effects of bleaching on restorative materials were material dependent. It is necessary to consider the type of the material before starting the treatment.

• 대한소아치과학회지
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• 제48권4호
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• pp.367-375
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• 2021

이 연구의 목적은 알카자이트 수복재와 자이오머에서 방출되는 불소가 상아질 접착층을 투과하는 유리되는 양을 측정하고 비교하는 것이었다. 알카자이트 수복재와 자이오머 및 불소 미함유 복합레진의 시편을 각 재료 당 20개씩 제작하여 그 중 10개의 시편에 상아질 접착제를 도포하였다. 만들어진 시편을 2.0 mL의 탈이온수가 들어있는 폴리에틸렌튜브에 넣고 37.0℃ 항온수조에 연구 기간동안 보관하였다. 보관 후 1일, 3일, 7일, 14일, 21일, 28일째에 불소 유리량을 측정하였으며 매 측정 후 탈이온수를 교체하였다. 상아질 접착제층 두께의 적절성은 시편을 추가로 제작하여 전계방사형 주사전자현미경으로 관찰하여 평가하였다. 알카자이트 수복재와 자이오머에 상아질 접착제를 도포한 경우 접착제가 불소의 유리를 완전히 차단하지는 않았지만, 유리된 불소의 양이 현저히 감소하였다. 28일간 측정한 알카자이트 수복재의 불소 유리량은 상아질 접착제의 유무와 관계없이 자이오머보다 크게 나타났다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.191-192
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• 2008

• Restorative Dentistry and Endodontics
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• 제12권1호
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• pp.95-105
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• 1986

For the purpose of obtaining a basic data in selecting a suitable material with clinical care, this study was designed to measure the shear stress and to examine the fracture pattern of various dentin bonding restorative materials using 43 extracted bicuspids. The following results were obtained. 1. In dentin, Silux/Scotchbond group showed the highest value ($34.5{\pm}14.7kg/cm^2$) and Fuji Ionomer Type II group and Heliosit/Dentin-Adhesit group showed almost same bond strength in the next place. Durafill/Dentin-Adhesive group showed an infinitesimal value. ($3.1{\pm}1.4kg/cm^2$) 2. Every group showed no difference in bond strength between upper and lower teeth. Between buccal and lingual surfaces. Fuji Ionomer Type II and Durafill/Dentin-Adhesive groups showed too. But, in Silux/Scotchbond and Heliosit/Dentin-Adhesit groups, it was shown that the bond strength in lingual was stronger than in buccal. 3. There was resin fracture with cohesive fracture of bonding agent in Enamel group. In dentin, adhesive-cohesive fracture and adhesive fracture were shown. 4. The stronger bond strength was, the more frequently cohesive fracture occurred. Dentin-Adhesit group showed specific shining appearance as if varnish became hard.

• 대한소아치과학회지
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• 제44권3호
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• pp.263-271
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• 2017

본 연구는 Molar-incisor hypomineralization(MIH)에 이환된 제1대구치를 그 결손의 크기 별로 분류를 시행하고, 수복치료 후 수복재료에 따른 예후 평가를 목적으로 수행되었다. MIH에 이환되어 맹출 후 치관 붕괴가 관찰된 제1대구치를 Class I에서 III까지 세 단계로 분류하고, 수복치료 이후 수행된 재치료 빈도를 Class와 수복재료별로 나누어 살펴보았다. MIH Class I 결손에서는 실런트, Class II 결손에서는 복합레진이 가장 높은 유지율을 보였다. Class III 결손에서는 기성금속관의 유지율이 가장 높게 나타났다.