• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.3
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• pp.45-54
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• 2017

With rapid urbanization and reckless urban development in the 21st century, the urban environment has gradually gotten worse, and urban heat island effect has been dramatically intensified. Thus, the importance of street greenery that can mitigate the urban heat island effect has further been highlighted. In this regard, this study was aimed at selecting suitable plant species for street greenery to reduce the urban heat island effect. Towards this end, five roads located in Seocho-gu, Seoul were selected as study sites, and plant species composition and difference of surface temperature were compared and analyzed in relation to the light transmittance. The street with the greatest temperature difference is Bangbae-ro(Platanus occidentalis). On the other hand, the road with the lowest temperature difference is Nambusunhwan-doro(Metasequoia Glyptostroboides). The effect of temperature reduction was found to be associated with light transmittance.Bangbae-ro(Platanus occidentalis) with the lowest light transmittance showed the highest temperature difference and Nambusunhwan-doro(Metasequoia Glyptostroboides) with the highest light transmittance showed the lowest temperature difference. It is analyzed that there are most differences in temperature when the amount of lights coming in between the crown is small. The temperature reduction effect can be obtained by planting deciduous broad-leaved trees. Also species with dense crown and broad width of crown will be able to maximize the effect of temperature reduction. In future studies, it will be necessary to expand the other species of trees in the street, and analyze the germicidal trees and shrubs as well as the differences in the packaging materials.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.2
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• pp.143-149
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• 2015

In esthetic treatments, it is important to consider the arrangement of teeth and the relation between the teeth and soft tissues. A precise diagnosis and establishing an appropriate treatment plan is essential in an esthetic treatment of anterior maxillary teeth. For a fixed prosthesis to meet esthetic expectations, It is crucial to achieve symmetry and adequate proportions of the gingival contour around the crowns. To achieve an esthetic improvement and creating a favorable environment for gingival healing of a physiologic gingival contour, gingivectomy, crown lengthening and forced eruption can be applied to the appropriate site. All ceramics or porcelain laminate veneer can be selected for esthetic improvement of teeth contour and shade. In this case report, malposition of the remaining teeth made it hard to get an esthetic appearance. Gingivectomy, crown lengthening and provisional restoration insertion were performed before the final prosthesis fabrication to reform the gingival form. This case presents satisfying result esthetically and functionally.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.715-721
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• 2003

Dental injuries with crown fracture occur frequently, especially in young patient Reattachment of the crown fragment has been shown to yield good esthetic results in that original tooth anatomy is restored with a material that abrades at a rate indntical to that of the adjacent tooth substance and at the same time permits continual monitoring of pulpal status through the fragment. Case 1 was complicated crown fracture with pin-point bleed ing, that was treated by direct pulp capping with calcium hydroxide and fragment reattachment. Case 2 was in trusive luxation with complicated crown fracture and was treated by pulp treatment and fragment reattachment. Case 3 was uncomplicated crown fracture, and fracture line involved slightly biologic width and treated by reattachment of the crown fragment.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.6
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• pp.800-805
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• 2000

In an effort to facilitate fabrication procedure of all ceramic crowns, a novel preparation method for all ceramic crown using alumina tape was developed. The alumina tape having a uniform thickness was cast by using Doctor blade method. The physical properties of newly introduced alumina tape has biaxial flexure strength of $500\sim600MPa$. The value of toughness is $3.18\sim3,28MPa.m^{1/2}$ which corelates with fracture and the linear shrinkage rate of the alumina tape is 0.44% during core production. The marginal fitness of the alumina tape all-ceramic restoration with $90{!`}$shoulder margin had average marginal discrepancy at $78.3{\S}$ > and average marginal gap at $44.4{\S}$ >. At the marginal preparation of $135{!`}$deep chamfer, the average marginal discrepancy at $82.1{\S}$ > and the average marginal gap at $40.2{\S}$ > had been reported. This fabrication procedure of all ceramic crowns with alumina tapes is easier and less technical sensitive for dental technicians. After restoration with new all ceramic crowns we followed the patients 2 years later, there were no complications as porcelain fractures or periodontal disease. We had good esthetic clinical results with new all ceramic crowns.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.12-20
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• 2021

The purpose of this retrospective study was to evaluate the survival rate by comparing Class II restoration using flowable resin composite with stainless steel crown in primary molars. Electronic medical records and radiographs of 1,504 primary molars with proximal caries of 590 patients from June 2015 to August 2019 were analyzed. With the collected data, survival analysis was performed using the Kaplan-Meier method. The 1-year survival rate of flowable resin composite in the primary molar was 98.5%, 3-year survival rate was 87.7%, and mean survival time was 39 months. There was no statistically significant difference between flowable resin composite and stainless steel crown (p = 0.896). Within the limits of this study, Class II restoration using flowable resin composite can be considered a promising option for the treatment of proximal caries in primary molars.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.262-271
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• 2020

To restore a tooth with a fracture line extending below the marginal bone level, a surgical crown lengthening procedure accompanied by ostectomy could be considered to expose the fracture line and reestablish the biologic width. However, this procedure could lead to esthetic failure, especially in the anterior teeth. Therefore, orthodontic extrusion, which elevates the fracture line from within the alveolar socket without sacrificing the supporting bone and gingiva, is recommended. This technique allows for the proper placement of the crown on a sound tooth structure, with the reestablishment of the biologic width. Alternatively, surgical extrusion is an one-step procedure that is simpler and less time-consuming than orthodontic extrusion; placing and adjusting the orthodontic appliance does not require multiple visits. This study presents successful restoration in 2 cases with a crown-tooth root fracture of the maxillary central incisor treated using a multidisciplinary approach through orthodontic extrusion or surgical extrusion followed by successful restoration.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.366-374
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• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.5
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• pp.28-39
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• 2003

This study was carried out to elucidate effective restoration measures for natural forest with recycling native tree un site from November 2001 to October 2002 to obtain a basic information for revegetation measure, eight experimental treatment was done and the length of stump, root-ball size of stump, antisepsis treatment of trunk cut, Planting season and contents of organic matter in soil were effective on regrowth of root-stock. Thirteen tree species including Quercus acutissima among twenty tree species showed outstanding sprout and survival rate(over 90 percent), Planting in November and combinated planting with 5 trees and 9 shrubs of root-stock per 100$m^2$ plot showed a good growth. And 10 percent of organic matter plot showed a good crown coverage.

• Restorative Dentistry and Endodontics
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• v.37 no.2
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• pp.114-118
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• 2012

Proximal caries or coronal defect in posterior teeth may result in the loss of proximal space and drifting of neighboring teeth, which makes restoration difficult. Inability to restore proper contours and to align tooth axis properly are commonly encountered problems when planning tooth restoration. Moreover, tilted teeth aggravate periodontal tissue breakdown, such as pseudo-pocket, and angular osseous defect. The purpose of this case presentation is to describe a simple technique for inducing minor tooth movement with orthodontic separating ring and provisional restoration modification. This method was used to create crown placement space on mesially tilted molar. This method is easy, simple and efficient technique which could be used in interproximal space gaining in selected situation.

• Journal of the Korean institute of surface engineering
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• v.40 no.4
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• pp.197-202
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• 2007

Fit of the restoration and its cementation procedure is crucial to both its short and long term prognosis. Marginal fit is affected by many variables during the fabrication process. These variables, being intrinsic properties of the materials or the clinical technique used, can cause changes in the size and shape of the definitive restoration. Even if all variables are controlled carefully, the seating of a restoration can still be affected due to insufficient space for the luting agent. The use of die spacer can reduce the elevation of a cast restoration of a prepared tooth, decreased seating time, improve the outflow of excess cement, and lower the seating forces. The purpose of this study was to evaluate the marginal fidelity according to die spacer application times and measurement site. Casting alloys were prepared and fabricated using non-precious metal at $950^{\circ}C$. Specimens are divided into four groups: I(die spacer painted casting for wax pattern), II(die spacer non painted casting for wax pattern). The specimens were cut and polished for marginal gap observation. The marginal gap was observed using scanning electron microscopy (SEM).