• The Journal of Korean Academy of Prosthodontics
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• v.41 no.1
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• pp.71-80
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• 2003

Development of new ceramic and esthetic need of patient increased the use of ceramic restorations. The purpose of this study was to confirm the possibility of recycling for IPS Empress2 which has a lot of advantages in esthetics. 1st, 2nd and 3rd pressed disc-shaped($10{\times}1.5mm$) IPS Empress 2 specimens were made with IPS Empress ingot(shade 200, Ivoclar, Liechtenstein) and pressing furnace(IPS Empress EP 500, Ivoclar, Liechtenstein). Flexure strength was measured with universal testing machine(Zwick 145641, Zwick, Germany), and color change and staining resistance of specimens were evaluated with colorimeter (Model TC-6FX, Tokyo Denshoku Co., Japan). The followings were drawn from this study : 1. Flexure strength of the 1st, the 2nd, and the 3rd pressed specimens showed 236.78 MPa. 247.16MPa, and 220.72MPa, respectively. Flexure strength of the 2nd pressed specimens was higher than others, but there's no statistical difference between them. 2. The color difference between the 1st and the 2nd pressed specimens was 3.25, and that between the 1st and the 3rd pressed specimens was 3.63(P<0.05). 3. The color change after staining of the 1st, the 2nd. and the 3rd pressed specimens were 1.43, 2.64, and 1.45, respectively. In this study, reused IPS Empress 2 specimens showed insignificant change of flexure strength and stain resistance, but they showed some color change according to reuse. From this results, the limited possibility of reuse for IPS Empress 2 could be considered.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.423-430
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• 2016

The implant prosthesis can be divided into the screw retained prosthesis and cement retained prosthesis. Each type has advantages as well as disadvantages which is unfavorable to maintain the implants. To overcome these drawbacks, T-screw system was developed. T-screw system which utilizes a lingual direction of the screw to retain the implant prosthesis, has advantages of retrievability of the prosthesis, passive fit, and possibility to form esthetic and functional occlusal surface. The prior prosthesis which utilized horizontal screws had difficulty in fabrication especially in the case of multiple units, and also limited use with all-ceramic prosthesis. In this case, fabricating the implant prosthesis by using the T-screw system showed superior results in easy maintenance, esthetics, and also functions. In addition, we are to report the method of using the T-screw system in implant prosthesis, such as multiple units of implant prosthesis and all ceramic prosthesis.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.126-133
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• 2018

The development of cone beam computerized tomography (CBCT) allows three-dimensional analysis of the patient's anatomy. The surgical guide is a combination of CBCT, computer-aided design/computer-aided manufacturing (CAD/CAM) and implant diagnostics software, which allows well planned prostheses design and ideal implant placement. Guided surgery minimizes possible anatomical damage and allows for more reproducible treatment planning. In this case, the operation time was shortened by using a surgical guide for multiple implants placement in a fully edentulous patient. Immediate loading were performed more easily using preliminary preparation of provisional prosthesis. The patient was satisfied with improved esthetics and chewing function.

• The Journal of Advanced Prosthodontics
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• v.3 no.3
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• pp.113-118
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• 2011

PURPOSE. The objective of the present study was to evaluate the effect of five different metal framework designs on the fracture resistance of the metal-ceramic restorations. MATERIALS AND METHODS. For the purpose of this study, the central incisor tooth was prepared, and the metal analogue of it and a master die were fabricated. The counter die with the 0.5 mm clearance was used for fabricating the wax patterns for the metal copings. The metal copings with five different metal framework designs were designed from Group 1 to 5. Group 1 with the metal collar, Group 2, 3, 4 and 5 with 0 mm, 0.5 mm, 1 mm and 1.5 mm cervical metal reduction respectively were fabricated. Total of fifty metal ceramic crown samples were fabricated. The fracture resistance was evaluated with the Universal Testing Machine (Instron model No 1011, UK). The basic data was subjected to statistical analysis by ANOVA and Student's t-test. RESULTS. Results revealed that the fracture resistance ranged from 651.2 to 993.6 N/$m^2$. Group 1 showed the maximum and Group 5 showed the least value. CONCLUSION. The maximum load required to fracture the test specimens even in the groups without the metal collar was found to be exceeding the occlusal forces. Therefore, the metal frameworks with 0.5 mm and 1 mm short of the finish line are recommended for anterior metal ceramic restoration having adequate fracture resistance.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.4
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• pp.805-812
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• 1997

Despite dentistry's attempts to improve the dental health of the public and to minimize the effects of caries, many children still present with extensive destruction of primary anterior teeth. One of dentistry's most challenging tasks is to repair these teeth with restoration which are durable, retentive, and esthetic. Esthetic restoration can often be achieved with polycarbonate crowns, strip crowns, conventional S-S crowns, open-faced S-S crowns, commercially veneered S-S crowns. But, all of these have limitation. Advances in restorative materials and metal-bonding procedures have made possible new restorative techniques that combine the advantages of S-S crowns with the cosmetics of composite restoration methods. The described technique of bonding composite to trimmed and fitted S-S crowns offers many advantages over other techniques currently used to restore primary anterior teeth. 1. If S-S crowns are accurate trimmed and contoured, good retention of crowns is achieved. 2. The patient time required is similar to that of conventional S-S crowns. 3. Good esthetics and high bond strengths are achieved. 4. It is possible to use this veneering technique intraorally on crowns that have fractured veneers.

• The Journal of the Korean dental association
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• v.58 no.2
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• pp.83-92
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• 2020

In the anterior maxillary area, dental implants for tooth replacement are challenging due to the need to satisfy high esthetic level as well as functionality. Immediate implant placement and provisionalization can dramatically reduce the edentulous period, and then fulfill patient's demand for esthetics. The aim of present case report is to demonstrate two cases that successfully restored single tooth with immediate implant placement and provisionalization in the anterior maxillary area. A 47 years old female was scheduled to replace her maxillary right central incisor due to crown-root fracture by trauma. Another 54-year-old female was planned to place dental implant following tooth extraction of maxillary right lateral incisor owing to continuous pus discharge despite repetitive treatments including apicoectomy. In these two cases, surgical and prosthetic procedures progressed in a similar way. After minimal flap elevation, atraumatic tooth extraction was performed. Implant was placed in proper 3-dimensional position and angulation with primary stability. Bone graft or guided bone regeneration for peri-implant bone defect was conducted simultaneously. Provisionalization without occlusal loading was carried out at the same day. Each definitive crown was delivered at 7 and 5 months after the surgery. Two cases have been followed uneventfully for 2 to 5 years of loading time. In conclusion, Immediate implant placement and provisionalization could lead to esthetic outcome for single tooth replacement with dental implant under proper case selection.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.4
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• pp.253-259
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• 2019

In this case report, gingival recession of the mandibular anterior teeth was treated with a laterally closed tunnel technique. Two patients had altered the inclination of mandibular anterior tooth during past orthodontic treatment and had periodontal thin biotype. The recipient site was formed by tunneling method, and the connective tissue graft obtained from the palatal side was placed in the tunnel, and the margins of flap were gathered at the center of the root and sutured. Despite the thin periodontal biotype, the root coverage was successfully obtained, keratinized gingiva was increased, and aesthetics were achieved by harmonizing with surrounding tissues in terms of shape and color.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.29 no.2
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• pp.66-74
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• 2020

Communication and cooperation between dentists and dental technicians are two essential elements for the fabrication of high quality 'custom' prosthesis. For successful communication and cooperation between the two groups, however, dentists and dental technicians must share common understanding about clinical dentistry. Ironically, it is often noticed that they are not really sharing the same clinical knowledge. Although there is a strong association between 'Emergence Profile' of implant prostheses and periodontal health or esthetics, no definite guideline has ever been provided for ideal emergence profile of implant prosthesis in literature. Problems resulted from inherent differences between implants and natural teeth must be acknowledged and shared between dentists and dental technicians so that they can come up with desirable clinical results with implant prostheses.

• The korean journal of orthodontics
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• v.37 no.5
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• pp.331-340
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• 2007

The aim of this study was to determine firstly the characteristics of esthetic lips in Korean females and secondly to measure the changes of the lips before and after anterior segmental osteotomy in bimaxillary protruded patients. Methods: Samples consisted of 30 models and 26 nonmodels, and 10 patients who had received anterior segmental osteotomy. Twelve linear measurements, 5 angular measurements, and the lip perimeter and area were measured. These results were compared for each group using unpaired and paired t-tests. Results: Full face width, nose to chin, upper vermilion height and angle, lateral heights at the point of the tips of Cupid's bow, central bow angle, and the lower lip to chin lengths were significantly greater in nonmodels than in models. However, overall lip width, lower vermilion height and angle, tip-to-tip of Cupid's bow lip perimeter, and lower vermilion area were greater in models than in nonmodels. Comparison of before and after anterior segmental osteotomy revealed that the values for the upper vermilion and lateral heights, the angle to Cupid's bow tip lengths, and upper vermilion area of post-operative patients had become similar to those of Korean female models. Our findings demonstrated that Korean female models have a fuller lower vermilion & thinner upper vermilion compared with nonmodel controls, as determined by the vermilion heights, angles, and areas. Conclusions: It will be helpful for clinicians to use these measurements as guidelines for improving patients' facial esthetics.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.3
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• pp.224-233
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• 2024

The patient was a 69-year-old male who had decreased VDO and overbite of the anterior teeth due to severe teeth wear. Complete mouth rehabilitation was planned to restore esthetics and function. Due to the presence of a subgingival finish line, poor fit of the margin of the temporary crown, and insufficient oral hygiene management, gingival overgrowth and bleeding occurred in many teeth, and inaccurate impressions were taken. After dividing each arch and taking partial impressions, a transfer coping was made using pattern resin on each working model die, and after being placed on the abutment teeth, a master cast was made through pick-up impression taking to produce prosthesis. In this case, the final prosthesis produced on the second master cast were fitted in terms of proximal contact, marginal fit, vertical occlusal dimension, facial appearance, esthetics, and occlusion. After complete mouth rehabilitation, the patient was satisfied with function and esthetic appearance.