• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.69-70
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• 2017

In Korea, silicone type sealant is widely used for construction site. Before the silicone type, urethane type is one of the main type sealants. However, the weathering property is less than the silicone type, the urethane type is replace by the silicone one. Still the urethane type is used for the inside of the buildings for the perimeter of the window. The silicone type sealants are better in weathering property than those of the urethane type sealants. Except the weathering property urethane type sealant has its own advantage like movement property, low cost and so forth. There are many research results for the outdoor weathering of the sealants, but in Korea there are no results for the outdoor weathering for construction sealants. This research is focused on the outdoor weathering of the urethane sealants, how to measure the degradation, and compare the products which used in Korea. The outdoor weathering test is usually time consuming, thus we designed specialized device for accelerating the result.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.429-438
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• 1994

Since the introduction of pit and fissure sealants in the early 1970's, many studies have been published amply documenting the efficacy of these materials as caries-preventive agents. However, the acceptance of the technique by dentist has been questionable. This survey was investigated the attitudes toward and use of pit and fissure sealants by dentist in Chonbuk area. The results were as follows: 1. Utilization of pit and fissure sealants is very high. Only 15% of dentists never use pit and fissure sealants, whereas 85% generally use pit and fissure sealants. 2. Most dentists reported that their knowledge of pit and fissure sealants was gained through dental schools education. 3. Concern about difficult to sell' to patient, poor retention of pit and fissure sealants and unsubstantiated by research were given as the main reasons why pit and fissure sealants was not used. 4. Patient demands and various educate program were given as important factors that would lead to increase use of pit and fissure sealants.

• Journal of Korean society of Dental Hygiene
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• v.22 no.5
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• pp.347-354
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• 2022

Objectives: This study aimed to evaluate the relationship between pit and fissure sealants of the molars, and caries prevalence and experience to assess the effect of sealants on caries prevention. Methods: Data from 16,119 people were extracted from the seventh Korean national health and nutrition examination survey, which was conducted from 2016 to 2018. Demographic, socioeconomic, oral health-related behavioral, and oral examination survey data were collected as independent variables. SAS statistics for complex samples and multiple logistic regression analysis (Windows ver. 9.4) was used for the statistical analyses. Results: Caries prevalence and experience were significantly associated with age, sex, daily toothbrushing frequency, interdental cleaning, and having molar sealant. Multiple logistic regression analysis revealed a significant association between having molar sealants and the caries prevalence and experience among participants under 30 years of age after adjusting socio-economic variables and toothbrushing-related factors. Conclusions: This study confirmed the effect of molar sealants on caries prevention in Korea. Our results support that the application of molar sealants in children, adolescents, and young individuals is effective in preventing caries.

• Journal of Applied Reliability
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• v.7 no.4
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• pp.149-162
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• 2007

Field and accelerated tests are performed to assess the service life of construction sealants. Mathematical degradation models for tensile strength and elongation, that are the two major performance characteristics of sealants, are derived from the test results. Accelerated degradation test methods for assessing service life of construction sealants are developed based on the degrading performance and a numerical example is provided.

• The Journal of the Korean dental association
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• v.49 no.1
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• pp.22-32
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• 2011

This paper reviewed the following subheadings and a few selected references in each section were discussed: ${\cdot}$ Sealant placed over caries; is it possible? Initial caries which is not sticky during proving is possible to be placed with sealants. ${\cdot}$ Prophylaxis of fissure; which method is most effective? Mechanical preparation with fissurotomy or resin polishing bur is one of the most effective method to clean the pit and fissure. ${\cdot}$ Glassionomer cement as a sealant; GIC, wheather it released fluoride or not, cannot be as cost-effective as resin-based sealants. ${\cdot}$ Sealant products; Color(white vs opaque), fluoride(containing vs not), filler component(filled vs non-filled) do not influenced the quality and retention of sealants. ${\cdot}$ Use of intermediate bonding agent to improve retention; Intermediate bonding may increase the retention rate of sealants ${\cdot}$ Penetration method of sealants; Several methods including waiting before light curing are recommended.

• Elastomers and Composites
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• v.34 no.3
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• pp.199-211
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• 1999

In this work, the effects of the addition of epoxy on the properties of PVC-sol sealants were investigated. PVC-sol was plasticized with dioctyl phthalates(DOP). Two kinds of epoxy resins having different epoxy equivalent weight (E.E.W.) were used. It was found that the properties of the PVC-sol sealants were significantly affected by the contents and types of the added epoxy resins. The viscosity behaviors of the epoxy-modified sealants, in the case of epoxy A addition, the viscosity was decreased with increasing the epoxy contents, but In the case of $CaCO_3$ addition, the viscosity was increased with increasing the $CaCO_3$ contents. The viscosity of epoxy modified sealants aged at $45^{\circ}C$ waterbath was decreased with increasing epoxy contents, since the epoxy acted on the sealants as a stabilizer. The thermal stability of the PVC-sol sealants was slightly improved by adding epoxy. The tensile strength and elongation of sealants modified with epoxy A(two functionalities of epoxy) were increased with increasing the epoxy contents up to a certain epoxy contents but was decreased with further increasing the epoxy contents. In the case of $CaCO_3$ addition, the tensile strength of sealants were decreased with increasing the $CaCO_3$ contents. In view of the electrical properties, such as tan ${\delta}$($0.1{\pm}0.04$) and ${\epsilon}_r$($0.5{\pm}0.04$), it was found that the epoxy modified sealants were as good as insulators.

• Journal of dental hygiene science
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• v.15 no.6
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• pp.768-774
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• 2015

The purpose of this study was to grasp the benefits from pit and fissure sealants and to analyze the factors of influencing the benefit amount by using the raw data of the Korea National Health and Nutrition Examination Survey for 2007~2013 targeting the subjects aged from 6 years in full to 18 years. The analysis was used STATA 11.0. As a result of the analysis, the following conclusions were obtained. It rose up to 1.24 pieces after carrying out the national health insurance coverage from averagely 0.93 piece until the year in 2007~2009 (up to November) when is before enforcing the national health insurance coverage in the pit and fissure sealants. The benefits from pit and fissure sealants depending on general characteristics were surveyed to be higher in the higher income level, in the more subscription to health insurance and private insurance, and in the more toothbrushing frequency per day. The factors that have influence upon the benefits from pit and fissure sealants were shown to include whether or not to have the national health insurance coverage in the pit and fissure sealants, income level, health insurance type and private insurance subscription appearance, and one-day toothbrushing frequency. Synthesizing the results, a rise in the benefits from pit and fissure sealants is shown in 2010 based on December 2009 when the national health insurance coverage in the pit and fissure sealants was implemented, but is showing the tendency of declining again from 2011. To increase the benefits from pit and fissure sealants, it is thought that the schemes will need to be discussed such as reinforcing publicity on the national health insurance coverage in the pit and fissure sealants, expanding a support for low-income bracket, and differentiating the outpatient cost sharing according to socio-economic level.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.39-47
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• 2017

Objectives: Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. Materials and Methods: Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). Results: Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. Conclusions: The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1115-1118
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• 2000

Specimens were cured by using a 1 mm (thickness) ${\times}$5 mm (diameter) teflon mold, and were immersed in artificial saliva and in 75% ethanol for 1, 7, 14, 21 and 28 days in order to quantify and to identify toxic components and to determine any degra dation byproducts of Bis-GMA that might be released from five commercially available resin-based dental sealants. In artificial saliva, the only released component was triethylene glycol dimethacylate (TEGDMA). In 75% ethanol, TEGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]propane (Bis-GMA) and urethane dimethacrylate (UDMA) were released highly at the initial stage, indicating that the amount of component released is not linearly correlated with the immersion time. The amount of released TEGDMA was found to be much higher in 75% ethanol than in artificial saliva. Importantly, bisphenol-A (BPA) was detected from all the uncured sealants tested, suggesting that all the sealants tested contain BPA as a contaminant.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.53-58
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• 2002

Electrical insulation and mechanical properties of the plasma sprayed oxide ceramic coatings were studied before and after the sealing treatment of the ceramic coatings. Plasma sprayed A1$_2$O$_3$-TiO$_2$ coating as the reference coating was sealed using three commercial sealants based on polymer. Penetration depth of the sealants to the ceramic coating was evaluated directly from the optical microscope using a fluorescent dye. It is estimated that the penetration depth of the sealants to the ceramic coating is from 0.2 to 0.5 mm depending on the sealants used. The preliminary test results with a DC puncture tester imply that the dielectric breakdown voltage mechanism of plasma sprayed ceramic coatings has been determined to be a corona mechanism. Dielectric breakdown voltage of the as-sprayed and as-ground samples have shown a linear trend with regard to the thickness showing an average dielectric strength of 20 kV/mm for the thickness scale studied. It is also shown that grinding the coating before sealing and adding fluorescent dye do not agent the penetration depth of sealants. All of the microhardness, two-body abrasive wear resistance, bond strength, and surface roughness of the ceramic coating after the sealing treatment are improved. The extent of improvement is different from the sealants used. However, three-point bending stress of the ceramic coating after the sealing treatment is decreased. This is attributed to the reduced micro-crack toughening effect since the cracks propagate easily through the lamellar of the coating without crack deflection and/or branching after the sealing treatment.