• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.381-386
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• 2017

PURPOSE. To integrate extra-oral facial scanning information with CAD/CAM complete dentures to immediately rehabilitate terminal dentition. MATERIALS AND METHODS. Ten patients with terminal dentition scheduled for total extraction and immediate denture placement were recruited for this study. The patients were submitted to a facial scanning procedure using the in-office PritiMirror scanner with bite registration records in-situ. Definitive stone cast models and bite records were subsequently submitted to a lab scanning procedure using the lab scanner (iSeries DWOS; Dental Wings). The scanned models were used to create a virtual teeth setup of a complete denture. Using the intra-oral bite records as a reference, the virtual setup was incorporated in the facial scan thereby facilitating a virtual clinical evaluation (teeth try-in) phase. After applying necessary adjustments, the virtual setup was submitted to a CAM procedure where a 5-axis industrial milling machine (M7 CNC; Darton AG General) was used to fabricate a full-milled PMMA immediate provisional prosthesis. RESULTS. Total extractions were performed, the dentures were immediately inserted, and subjective clinical fit was evaluated. The immediate provisional prostheses were inserted and clinical fit, occlusion/articulation, and esthetics were subjectively assessed; the results were deemed satisfactory. All provisional prostheses remained three months in function with no notable technical complications. CONCLUSION. Ten patients with terminal dentition were treated using a complete digital approach to fabricate complete dentures using CAD/CAM technology. The proposed technique has the potential to accelerate the rehabilitation procedure starting from immediate denture to final implant-supported prosthesis leading to more predictable functional and aesthetics outcomes.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.11-20
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• 2004

Problem : The several studies were reported to the effects of individual tooth tray with the parallel tooth, but not reported to the effect of individual tooth tray with severe undercut in impression making. Purpose : The purpose of this study is to examine the effect of individual tooth tray; 1) the accuracy of impression in terms of distance. 2) reproducibility of pocket. Material and methods : In this study, a metal model with 3 teeth including tooth prepared 30-degree undercut and gingival crevice of the depth 5mm, width 0.4mm was cast. Impressions of the metal model were taken in 5 times used 4 kinds of impression materials with individual tooth tray and another impression taking were made with conventional method without individual tooth, used same materials, procedure. The stone models were made. Distances between abutments were measured with a Micromeasurescoup-mm. Result : The following results were obtained ; 1. In the comparisonof inter-abutment distance between parallel tooth without individual tooth tray, 4elastomeric materials have not significant difference to the metal model(p>0.05). 2. In the comparisonof inter-abutment distance with undercut tooth without individual tooth tray, 4elastomeric materials have a significant difference to the metal model(p<0.05), especially polyether's dimensional change is large. 3. If individual tooth tray was used to take impression in abutment teeth with severe undercut, more stable results was achieved easily than conventional method. (p>0.05). 4. It is not true that the pressure of impression material with individual tooth tray increased to gingival sulcus. Conclusion : By the results, I knew the fact that individual tooth tray was useful impression method on the teeth with severe undercut for the dimensional stability. Also, I could not confirm the fact that individual tooth tray would increase the penetrating pressure into cervice.

• Journal of Technologic Dentistry
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• v.39 no.1
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• pp.17-24
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• 2017

Purpose: The purpose of this study was to evaluate the internal fitness of the resin coping that was fabricated by the traditional and Digital manufacturing methods through 3-dimensional analysis. Methods: maxillary right second molar was chosen implant master model. Custom-built impression trays were manufactured. After screwing the pick-up impression coping onto the master cast, impressions were made with silicone impression. The Working model was then made with type IV stone. The coping was fabricated: SLAC group (n=8), APPC group (n=8), LAPC group (n=8) Resin coping data was measured by using a three-dimensional evaluation program. Internal fitness was calculated by RMS (Root Mean Square).It measures mean and Standard Deviation (SD). Results: Three groups are measured $47.11{\pm}(3.08){\mu}m$ total RMS of SLAC group, $48.35({\pm}1.55{\mu}m)$ for total RMS of LAPC group, $43.45{\pm}2.09{\mu}m$ for total RMS of APPC group. Measured value is gradually increased. Followed by autopolymerized pattern resin; Stereolithography resin, Light-activated pattern resin But there were no differences stastically(P>0.321). Conclusion: Evaluation of internal fitness on Resin copings was fabricated by three-ways methods showed that no differences statistically significant and clinically acceptable results.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.179-186
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• 2013

PURPOSE. One of the most important factors in evaluating the quality of fixed dental prostheses (FDPs) is their gap. The purpose of this study was to compare the marginal and internal gap of two different metal-ceramic crowns, casting and selective laser sintering (SLS), before and after porcelain firing. Furthermore, this study evaluated whether metal-ceramic crowns made using the SLS have the same clinical acceptability as crowns made by the traditional casting. MATERIALS AND METHODS. The 10 study models were produced using stone. The 20 specimens were produced using the casting and the SLS methods; 10 samples were made in each group. After the core gap measurements, 10 metal-ceramic crowns in each group were finished using the conventional technique of firing porcelain. The gap of the metal-ceramic crowns was measured. The marginal and internal gaps were measured by two-dimensional and three-dimensional replica techniques, respectively. The Wilcoxon signed-rank test, the Wilcoxon rank-sum test and nonparametric ANCOVA were used for statistical analysis (${\alpha}$=.05). RESULTS. In both groups, the gap increased after completion of the metal-ceramic crown compared to the core. In all measured areas, the gap of the metal cores and metal-ceramic crowns produced by the SLS was greater than that of the metal cores and metal-ceramic crowns produced using the casting. Statistically significant differences were found between cast and SLS (metal cores and metal-ceramic crown). CONCLUSION. Although the gap of the FDPs produced by the SLS was greater than that of the FDPs produced by the conventional casting in all measured areas, none exceeded the clinically acceptable range.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.560-569
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• 1999

Blood supply rather than nerve supply implies pulp vitality. To evaluate pulp vitality clinically, electric pulp test and thermal test which are based on sensory nerve response have been used in addition to many auxiliary data such as past dental history, visual inspection, radiographic examination, percussion, palpation and transillumination test. However, reactivity of the nerves to the stimulation is not synonymous with normalcy. Therefore measurement of pulpal blood flow using a laser Doppler flowmeter became a new trial to test the pulp vitality. The purpose of the present study was to evaluate normal pulpal blood flow level of maxillary teeth in adult to provide a guideline in determining the vitality of dental pulp. Pulpal blood flow was measured in maxillary central and lateral incisors, canines, first and second premolars and first molars of seventy nine adults of 22 - 30 years old using a laser Doppler flowmeter (PeriFlux 4001, Perimed Co., Stockholm, Sweden, 780 nm infrared laser, 1mW). For directly-made splints, silicone rubber impressions were taken directly from the mouth. For indirectly-made splints, alginate impressions were taken from the mouth and stone cast were made. After making depressions on the buccal surfaces of the cast teeth to indicate the hole positions, second impressions with vinyl polysyloxane putty were taken from the cast. Holes for the laser probes were made at the putty impressions 4mm above the gingival level. Laser probe (PF416 dental probe, 1.5mm) was inserted in the prepared hole and the splint was set in the mouth. After 10 minutes of patient relaxing, pulpal blood flow was recorded for 5 minutes on each tooth. The recorded flow was saved in the computer and calculated with a software 'Perisoft' version 5.1. Pulpal blood flow was also recorded in six teeth of five individuals with no response to electric pulp test and cold test, with periapical radiolucency, or with history of root canal treatment to compare with nonvital teeth. The difference between the mean flow values of each group of teeth were analyzed using one-way ANOVA and Duncan's Multiple Range test. The results were as follows: 1. The average pulpal blood flow values of all the tested teeth of each location were between 9 - 16 Perfusion Unit. Pulpal blood flow value was highest in maxillary lateral incisors, followed by first premolars, second premolars, canines, central incisors, and then first molars (p<0.01). 2. In six anterior teeth, indirectly-made splint group showed higher pulpal blood flow values than directly-made splint group (p<0.01). In posterior teeth, however, there was no significant flow value difference between directly-made splint group and indirectly-made splint one (p>0.05). 3. Teeth with vital pulps showed higher signal values than teeth with nonvital pulps (p<0.01), and the flow photographs showed heartbeat-synchronous fluctuations and vasomotions, while those were absent in non vital tooth.

• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.213-222
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• 1998

Covering polmer mortar as a filter for permeable polymer concrete on the base polymer concrete is nessary for good permeability from infiltration continuously. Therefore, three covering polymer mortars on the optimum base polymer concrete were cast immediatly following on the casting of the base polymer concrete. They are tested for compressive and flexural strengths, adhesion in tension, hardening shrinkage and permeability, and the effects of the mix proportioning factors on the properties of the permeable polymer concrete are discussed. From the test results, increase in the compressive strength and decrease in the coeffiecient of permeability of base polymer concrete are clearly obserbed with increasing filler-binder ratio. The base polymer concretes having a compressive strength of 9.4~28.3MPa and a coefficient of permeability of 0.12~1.93 cm/s can be produced in the consideration of the mix proportioning factors. Binder and filler contents in mix proportions had a great influence on the permeability of polymer concretes. The mechanical properties of permeable polymer concretes covered with polymer mortar using crushed stone are superior to other filters, and hardening shrinkage is the smallest in filters. It is apparent that adhesion between the base polymer concrete and polymer mortar is affected by the degree of hardening shrinkage. From this study, proper mix proportions can be recommended in the consideration of properties of the permeable polymer concrete.

• The Korean Journal of Pain
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• v.6 no.2
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• pp.275-279
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• 1993

Reflex sympathetic dystrophy is a syndrome characterized by persistent, burning pain, hyperpathia, allodynia & hyperaesthesia in an extremity, with concurrent evidence of autonomic nervous system dysfunction. It generally develops after nerve injury, trauma, surgery, et al. The most successful therapies are directed towards blocking the sympathetic intervention to the affected extremity by regional sympathetic ganglion block or Bier block with sympathetic blocker; other traditional treatments include transcutaneous electrical stimulation, immobilization with cast & splint, physical therapy, psychotherapy, administration of sympathetic blocker, calcitonin, corticosteroid and analgesic agents. The purpose of this report is to evaluate and describe the effects of magnetic resonance following unsatisfactory results with traditional treatments of RSD. A 17 year old female patient, 1 year earlier, had received excision and drainage of pus at the right femoral triangle due to an injury caused by a stone. Afterwards, she experienced burning pain, knee joint stiffness, and muscle dystrophy of the right thigh, especially when standing and walking. Despite a year of number of traditional treatments such as: lumbar sympathetic block, continuous epidural analgesia, transcutaneous electrical stimulation, & administration of predisolone, her pain did not improve. Surprisingly, the patients was able to walk free from pain and difficulty after just one application of magnetic resonance. The patient has been successfully treated with further treatment of two to three times a week for approximately ten weeks. More recently, magnetic resonance has been demonstrated to produce effective results for the relief of pain in a variety of diseases. From our experiences we recognize magnetic resonance as a therapeutic modality which can provide excellent results for the treatment of RSD. It has been suggested that polysynaptic reflex which are disturbed in RSD may be modulated normally on the spinal cord level through the application of magnetic resonance.

• Science of Emotion and Sensibility
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• v.26 no.4
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• pp.71-92
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• 2023

This study investigates the symbolism and meaning of the bead design, its relationship with the Silla culture, and the conditions of glass bead manufacturing to verify the theory of Silla's production of Silla face-inlaid glass beads with excellent artistry and technology. The research method includes investigating the design analysis, ancient documents, myths, relics, glass, and metal production techniques. Moreover, Hongshan cultural relics and other cases of inlaid glass beads were collected. There are records in the literature that the people of Makhan, Buyeo and Silla of ancient Korea people considered beads as treasures and used them for accessories. It was confirmed that all the design elements of the bead-patterned hair topknot, golden crown, birds, and flower trees were closely related to the myth of Kim Al-ji of Silla, the oviparous tales and the sacred birds and divine beasts of the north. Moreover, the pattern and arrangements were found to be similar in other Silla relics. The origin of beads and face pendants was Hongsan culture, and a stone cast for beads was discovered in Bukpyo of Gojoseon, the lower-level culture of Hajiajeom. In addition, excavating inlaid glass beads from Sik-ri tombs of Korea and a face-inlaid glass bead from Toganmori tombs in Japan confirms the theory of Silla's production. The fact that the Baekje people of ancient Korea had a glass bead manufacturing office in Japan in the fifth centuries suggests that the Silla people also had a manufacturing plant in Java, Indonesia, because this place was a crossroads of Silla's Sea Silk Road and a source of raw materials and labors with a close relationship to Silla. Therefore, the face-inlaid glass bead was indeed self-made by Silla, who possessed the tradition of bead myths and hair topknot, and the high-level skills such as gold crowns and metal inlays.

• 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.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.174-197
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• 2024

Personal ornaments made from precious metals that have been excavated from tombs dating to the Maripgan period (4th-6th century) of the Silla Kingdom are a major subject of analysis in the study of gender and hierarchy among the tomb occupants. Nonetheless, bracelets had been neglected until Ha Daeryong's recent research on determining gender through bracelets attracted attention. Accordingly, an examination and organization of the fundamental elements of Silla bracelets was needed. In response, this paper examines their physical characteristics, appearance, changes over time, and related wearing practices. The data for this study is derived from 176 bracelets, mostly made from silver or gold. Copper and glass bracelets are also included. Many of them were cast in a single-use earthen mold. Even the notched and protruding designs were created by casting rather than carving. Glass bracelets and bracelets with dragon designs were made using molds with round cavities. Excluding those produced using metal sheets, the rest of the bracelets are thought to have been cast in a mold with a long-string-shaped cavity and then bent round. After being bent, the two ends were either soldered together (closed type) or left open (open type). As demonstrated in the study by Lee Hansang, Silla bracelets evolved from plain rounded rod-shaped bracelets, such as the one excavated from the Northern Mound of Hwangnamdaechong Tomb, to versions with notched designs, and eventually to those with protruding designs, which gained popularity by the sixth century. The precedents of plain rounded rod-shaped bracelets are presumed to have been thin rod-shaped bracelets from the Proto-Three Kingdoms period. Bracelets need to be fit to the wrists so that they do not slip off easily when worn. The open type design was the preferable way to achieve this. Moreover, given the ductility of gold, silver, and copper, it seems that it would have been possible to stretch or deform them. In the end, I concluded that even if a bracelet is too small to pass man's hand, the open type could have been worn. Furthermore, if a closed-type bracelet were pressed into an oval shape, it would not be impossible for a man to put it on. When bracelets are divided according to their degree of deformability into type A (the open type) through type D, which is almost impossible to deform, type A is commonly found with wearers of thin hollow earrings, and types C and D (which are difficult to deform) are not found with wearers of thin hollow earrings, but only with wearers of thick hollow earrings. Therefore, it can be seen that men were allowed to wear bracelets, and the existing studies that differentiate between men and women based on the wearing of thin hollow earrings, thick hollow earrings, and swords remain valid.