• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.81-92
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• 2014

It is so hard to obtain optimal anterior esthetics in the implant prosthesis. This is not only because of hard and soft tissue problem such as alveolar bone resorption and interdental papilla loss but also because of prosthetic limitation related to marginal exposure of metal abutment and metal ceramics and low transillumination. In this case, guided soft tissue healing is obtained using a long term provisional restoration with soft and hard tissue augmentation or immediate implantation. Then, this healed tissue is transferred to final master model using a customized impression coping and the implant is restored with a customized zirconia abutment and a all ceramics. This case presents satisfying result esthetically and functionally.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.3
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• pp.261-270
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• 2021

Purpose. The aim of this study was (1) to compare the reverse engineering technique with other existing measurement methods and (2) to analyze the effect of implant angulations and impression coping types on implant impression accuracy with reverse engineering technique. Materials and methods. Three different master models were fabricated and the distance between the two implant center points in parallel master model was measured with different three methods; digital caliper measurement (Group DC), optical measuring (Group OM), and reverse engineering technique (Group RE). The 90 experimental models were fabricated with three types of impression copings for the three different implant angulation and the angular and distance error rate were calculated. One-way ANOVA was used for comparison among the evaluation methods (P < .05). The error rates of experimental groups were analyzed by two-way ANOVA (P < .05). Results. While there was significant difference between Group DC and RE (P < .05), Group OM had no significant difference compared with other groups (P > .05). The standard deviations in reverse engineering were much lower than those of digital caliper and optical measurement. Hybrid groups had no significant difference from the pick-up groups in distance error rates (P > .05). Conclusion. The reverse engineering technique demonstrated its potential as an evaluation technique of 3D accuracy of impression techniques.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.298-305
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• 2016

The maxillary anteriors play an important role in esthetics. Therefore after extraction, it is crucial to preserve the hard tissue and soft tissue in order to promote esthetics of restoration. There are several challenges when restoring the maxillary anteriors via implant. Some of the challenges are be maintaining consistency with neighboring teeth in terms of shade, form, and texture : as well as having harmonious emergency with the gingival margin. In this case, a traumatized patient with crown-root fracture of the maxillary central and lateral incisors is presented. The cracked teeth were extracted, and implants were inserted with bone grafts to compensate the volume of damaged area of the maxillary anterior. Cantilever implant prosthetics were planned while precise adjustments to the gingival area were made using customized impression coping to perform the esthetic restorations. The final outcome of the treatment was satisfying in both esthetic and utilitarian perspective.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.1
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• pp.1-13
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• 2001

An absolutely passive fit at the interface with the superstructure and the abutment cylinders is need for implant longevity. In this study, a method of cast framework correction using spark erosion technology was evaluated. Electric discharge machining(EDM) is a process that uses electrical discharges, or sparks, to machine metal, The surface being machined is bombared with high-intensity electrical energy pulses that gradually melt away the stock until the desired configuration is obtained. Master model was fabricated by using metal block impression analogue, which fired 5 Branemark squared impression coping in an arc shaped metal block. Then framework using 4mm standard gold cylinder and type IV gold alloy was fabricated. In order to measure the fit of the framework we used both contact and noncontact coordinate measurement machine and data was processed by computer program. After superimposition of gold framework and master model numeric image data the distances between gold cylinder bearing surfaces and abutment replica bearing surfaces, and the angle deviations between gold cylinder and abutment replica centroid points were calculated. The results were as follows 1 The total mean distance (p<0.01) and standard deviation (p<0.001) between the gold cylinders and abutment bearing surfaces were significantly decreased after EDM 2. The total mean of maximum distances was significantly decreased after EDM (p<0.05). 3. After EDM, the mean angle deviation between centroid points was decreased.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.201-208
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• 2008

Statement of problem: A new implant impression technique which use abutments as impression coping, and use resin cement as a splinting material was described. Accuracy of this technique was compared with conventional closed tray and resin splinted open tray technique for a $15^{\circ}$ angled 3-implant model Material and methods: A dental stone master model with 3 linearly positioned implant analogue and a reference framework which was passively fitted to it were fabricated. The center analogue was perpendicular to the plane of model and the outer analogues had a $15^{\circ}$angulation forward or backward. 10 closed tray impressions, 10 resin splinted open tray impressions, 10 abutment-resin framework cementation impressions and 10 abutment-metal framework cementation impressions were made with additional silicone material and poured with dental stone. A light microscope with image processing was used to record the vertical gap dimension between reference framework and analogue of duplicated cast made with each 4 impression techniques. Statistical analysis used one-way ANOVA with post-hoc tests Tukey test of .05 level of significance Results: Significant difference in the vertical gap dimension was found between closed tray technique; 74.3 (${\pm}33.4$)${\mu}m$ and resin splinted open tray technique, and two other new technique. (P<.05) Abutment-metal framework cementation technique;42.5 (${\pm}11.9$)${\mu}m$ was significantly different from resin splinted open tray technique. (P<.05) Abutmentresin framework cementation technique;51.0 (${\pm}14.1$)${\mu}m$ did not differ significantly from resin splinted open tray technique;50.3 (${\pm}16.9$)${\mu}m$. (P>.05) Conclusion: Within limitations of this study, the accuracy of implant level impressions of resin splinted open tray technique was superior to that of closed tray technique. A new technique using abutment and metal framework cementation was more accurate than resin splinted open tray technique.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.1
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• pp.43-48
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• 2003

During the past several years, significant advances have occurred in the utilization of osseointegrated implants for the treatment of partially edentulous patients. One of the biggest purposes for treating of these patients is the high demand for improved esthetics, especially in the anterior region. For this esthetics, the new trend in dental implants is the immediate placement and immediate superstructure fabrication. The refined surgical technique, the skillful soft tissue management, and the proper prosthetic coordination are the main factors to achieve natural looking of implant supported prosthesis. The customized provisional restoration and the customized impression coping are recommended for the optimal peri-implant soft tissue contour. The basic concept of Frialit 2 system was the immediate replacement of a tooth with root-analog fixture after extraction. This system guarantees an ideal result in function and esthetics. The ceramic abutment system offers improved quality in the respect of esthetics, fitness, translucency, and biocompatibility. In this clinical report, the final restoration made with IPS Empress 2 crown on the CeraBase abutmen of Frialit 2 system allowed the reproduction of the natural vitality of tooth and adjacent gingiva.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.25 no.1
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• pp.35-49
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• 2016

With the increasing demand for aesthetic implant dentistry, the importance of implant restoration is emphasized not only in the functional aspect but also in the aesthetic aspect. The aesthetic restoration of dental implants in the anterior maxilla is a challenge for clinicians because it requires proper harmony in three following conditions; reconstruction of hard tissue, soft tissue, and aesthetic prosthesis. The soft tissue aesthetics are dependent upon the condition of the supporting hard tissue because the osseous structure provides a framework for the development of a healthy and aesthetic soft tissue interface. Therefore, the augmentation of hard tissue is a first step and especially, optimal 3-dimensional position of implant is the most important factor in aesthetic implant restoration. The management of soft tissue is a second step, and the final step is a restoration of harmonic prosthesis using provisional restoration with proper emergence profile. This clinical report describes the procedure of bone augmentation in labial dehiscence defect, Vascularized Interpositional Periosteal-Connective Tissue (VIP-CT) flap for aesthetic anterior soft tissue, and the importance of provisional restoration and impression taking stage with customized impression coping.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.61-72
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• 2020

The fear of crime, discussed in the early 1960s in the United States, is a psychological response, such as anxiety or concern about crime, the potential victim of a crime. These anxiety factors lead to the burden of the individual in securing the psychological stability and indirect costs of the crime against the society. Fear of crime is not a good thing, and it is a part that needs to be adjusted so that it cannot be exaggerated and distorted by the policy together with the crime coping and resolution. This is because fear of crime has as much harm as damage caused by criminal act. Eric Pawson has argued that the popular impression of violent crime is not formed because of media reports, but by official statistics. Therefore, the police should watch and analyze news related to fear of crime to reduce the social cost of fear of crime and prepare a preemptive response policy before the people have 'fear of crime'. In this paper, we propose a deep - based news classification system that helps police cope with crimes related to crimes reported in the media efficiently and quickly and precisely. The goal is to establish a system that can quickly identify changes in security issues that are rapidly increasing by categorizing news related to crime among news articles. To construct the system, crime data was learned so that news could be classified according to the type of crime. Deep learning was applied by using Google tensor flow. In the future, it is necessary to continue research on the importance of keyword according to early detection of issues that are rapidly increasing by crime type and the power of the press, and it is also necessary to constantly supplement crime related corpus.

• The Journal of Advanced Prosthodontics
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• v.9 no.3
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• pp.176-181
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• 2017

PURPOSE. The purpose of this study was to evaluate the marginal and internal gaps of Ni-Cr and Co-Cr copings, fabricated using the dental ${\mu}-SLA$ system. MATERIALS AND METHODS. Ten study dies were made using a two-step silicone impression with a dental stone (type IV) from the master die of a tooth. Ni-Cr (NC group) and Co-Cr (CC group) alloy copings were designed using a dental scanner, CAD software, resin coping, and casting process. In addition, 10 Ni-Cr alloy copings were manufactured using the lost-wax technique (LW group). The marginal and internal gaps in the 3 groups were measured using a digital microscope ($160{\times}$) with the silicone replica technique, and the obtained data were analyzed using the non-parametric Kruskal-Wallis H test. Post-hoc comparisons were performed using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The mean (${\pm}$ standard deviation) values of the marginal, chamfer, axial wall, and occlusal gaps in the 3 groups were as follows: $81.5{\pm}73.8$, $98.1{\pm}76.1$, $87.1{\pm}44.8$, and $146.8{\pm}78.7{\mu}m$ in the LW group; $76.8{\pm}48.0$, $141.7{\pm}57.1$, $80.7{\pm}47.5$, and $194.69{\pm}63.8{\mu}m$ in the NC group; and $124.2{\pm}52.0$, $199.5{\pm}71.0$, $67.1{\pm}37.6$, and $244.5{\pm}58.9{\mu}m$ in the CC group. CONCLUSION. The marginal gap in the LW and NC groups were clinically acceptable. Further improvement is needed for CC group to be used clinical practice.

• Anxiety and mood
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• v.6 no.1
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• pp.17-23
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• 2010

Objective : This study compared the psychological stresses of depressed patients' families with those of schizophrenic patients' families. We investigated the influence of depressive patients' clinical features and their families' demographic characteristics on the families' depressive symptoms and stresses. Methods : Participants were 23 family members of depressed patients and 20 family members of schizophrenic patients. We measured the patients' clinical features (duration of illness, number of previous hospitalizations, and satisfaction with medication), and each family member's socioeconomic status and psychological characteristics (depressive mood, anxiety, family stress, and stress response), analyzing the data via independent t-test, chi-square test, and correlation and hierarchical multiple regression analyses. Results : The depressed patients' average clinical global impression (CGI) was significantly higher than that of the schizophrenic patients. The depressed patients' family members showed stress responses significantly higher than those of schizophrenic patients' family members. Furthermore, in depressed patients, frequency of hospitalization was positively correlated with family members' stat anxiety. For both patient types, family stress was positively correlated with the patient's severity of illness and the family's state anxiety, trait anxiety, and stress response ; socioeconomic status was positively correlated with the family's depressive symptoms ; the family's state anxiety positively correlated with the family's trait anxiety and stress response ; and the family's trait anxiety positively correlated with the family's stress response. Socioeconomic status predicted the family's depressive symptoms, and socioeconomic, illness severity and stress response predicted family stress. Conclusion : These findings suggest that both depressed patients' families and schizophrenic patients' families suffer from psychological stress. The study data also have important clinical implications, in that families of depressed patients need psychiatric intervention, as well as the patients themselves. In particular, family intervention should focus on psycho-education and stress coping strategies.