• 치위생과학회지
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• 제14권3호
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• pp.405-410
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• 2014

본 연구는 심미보철 치료에서 사용되는 금속도재관 제작시 Ni-Cr alloy 하부 구조물에 상부도재를 축성하고 소성하는 과정이 완성된 보철물의 적합도에 미치는 영향을 조사함으로써 임상적 허용을 재확인하기 위함이다. 1차로 lost wax technique으로 제작된 NCC (Ni-Cr alloy core)의 변연 및 내면 적합도를 측정하였고, 2차로 NCC에 상부도재 축성, 소성하여 금속도재관을 최종 완성하여 2차로 측정한 뒤비교한 결과는 다음과 같다. 금속도재관 제작 시 Ni-Cr alloy로 제작된 코어 위에 상부도재를 축성하고 소성하는 과정이 금속 도재관의 적합도를 악화시키는 결과를 보였으며, 부위 별 구분 없이 두 그룹에서 측정된 모든 값의 평균을 비교한 결과 NCC 그룹에서는 $67.1{\pm}23.3{\mu}m$, NMC 그룹에서는 $74.4{\pm}21.9{\mu}m$로 나타났으며 통계적으로 유의한 차이를 보였다(p<0.05). 이와 같은 결과를 토대로 Ni-Cr alloy로 금속도재관 제작 시 상부도재를 축성하는 과정에서 적합도를 악화시킨다는 결론을 얻었으나, 본 실험에서 측정된 결과 값은 임상적 허용 수치($120{\mu}m$)를 넘지 않아 적합도의 기준으로 평가하였을 때 임상적으로 허용 가능할 것으로 생각된다.

• Journal of Periodontal and Implant Science
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• 제34권4호
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• pp.819-836
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• 2004

Nowdays, the awareness of implant treatment has grown rapidly among dentists and patients alike in Korea, as it becomes a widely accepted treatment. The reason is that unlike crown and bridge or denture treatment, implant treatment helps preserve existing bone and improve masticatory functions. So, It is needed understanding about the type, distribution of implant patient. The following results on patient type and implant distribution were compiled from 4433 implant cases of 1596 patients treated at the periodontal dept. of Y University Hospital during 1992 to 2004. 1. There are no dissimilarities between men and women, with patients in their 40, 50s accounting for 52.5% of patients and 57.5% of implant treatments; the largest share of patients and implant treatments. 2. Mn. posterior area accounted for 54.9% of implant treatments followed by Mx. posterior area(27.6%), Mx anterior area(11.9%) and Mn anterior area(5.6%). 3. Partial edentulous patients treated by single crown and bridge-type prosthesis accounted for 97.5% and fully edentulous patient accounted for the remaining 2.5%. 4. The major cause of tooth loss is periodontal disease, followed by dental caries, trauma and congenital missing. Also, older people are more likely to suffer from tooth loss due to periodontal disease rather than dental caries. 5. In the distribution of bone quality for maxillae, type III was most, followed by type II, r type IV and r type I. As for mandible, type II was most, followed by type III, type IV and for type I. 6. In the distribution of bone quantity for maxillae, type C was most, followed by type B, type D, type A, and for type E. As for mandible, type B was 52% most, followed by type C, type D, type A and type E. 7. The majority of implants were those of 1O-14mm in length (85.2%) and regular diameter in width (64%). The results provided us with basic data on patient type, implant distribution, bone condition, etc. We wish that our results coupled with other research data helps assist in the further study for better implant success/survival rates, etc.

• 대한치과의사협회지
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• 제52권6호
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• pp.354-362
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• 2014

With the development of digital dentistry, various intra-oral scanners which acquire intraoral image without conventional impression taking and stone pouring steps have been introduced. Fixed dental prostheses such as inlay, onlay, crown, and bridge fabricated by CAD/CAM technique combined with digital impressions is getting popular due to the recent rapid progress of digital impression taking system. In comparison with traditional prosthetic procedure, the advantages of intraoral image acquiring and CAD/CAM technique are as follows; the omission of conventional impression materials, reduced workflow step, and increased efficiency by online communication with clinic and laboratory. This review article covers some opinions about the suitable scanning procedures for the various prosthodontic treatments and the utilization of digital intraoral scanner and CAD/CAM system.

• 대한치과의사협회지
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• 제12권8호
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• pp.613-617
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• 1974

The authors have studied the marginal leakage of various dental cements; Fynal cement (Caulk), Zinc cement (S.S. White) Carbo cement (Shofu, Poly-carboxylate cement), EBA cement (Opotow alumina cement), Propac (G-C's zinc oxide euginol cement), and Super cement (Shofu oxyphosphate zinc cement), by means of penetration of 2% methylene blue solution between orden crown restorations and human teeth in 150 cases. The result revealed as follow 1. None of the cements tested were free from dye penetration. 2. There was a wide difference in dye penetration among the trade brands of dental cement when immersed in dye solution before setting of cements. 3. EBA cement and Carbo cement showed comparatively low grade of dye penetration at the restorative margins.

• 대한치과의사협회지
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• 제48권10호
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• pp.754-761
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• 2010

Horizontal root fractures are defined as those that involve cementum, dentin and pulp, comprising from 0.5 to 7% of injuries in permanent dentition on dental trauma. Diagnosis is made through clinical findings and radiographic exams, the latter frequently being limited by the position of the fracture line. Treatment varies according to the displacement of crown portion and vitality of the fragments. Authors describe clinical cases of maxillary right central incisor with horizontal root fractures in dental clinic, Jeju National University Hospital.

• 대한치과의사협회지
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• 제25권8호통권219호
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• pp.783-788
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• 1987

The authors observed the two cases of Rieger's syndrome in 21-year-old male and 13-year-old female with a chief complaint of Partial anodontia of permanent teeth on both jaws. We had done the laboratory and ophthalmic examinations and had taken radiographs. Final diagnosis was established as Rieger's syndrome. We obtained the results as follows, 1. There was no peculiar hereditary tendency in them. 2. The patients had no disturbance of general physical activity and mentality. 3. The male patient had pseudoprogenathism, concave profile, congenital missing on upper anterior and second premolar teeth, and conical shaped crown of upper len celral incisor. The female patient had also pseudoprognathism, concave profile, thickened upper labial frenum, decreased upper dental arch width, congenital missing on upper anterior teeth, and delayed eruption of second premolars. 4. The ophthalmic symptoms that were ins abnormalities, decreased visual acuity, and increased intraocular pressure were present. 5. The abnormalities except dental and ophthalmic abnormalities were not round.

• Restorative Dentistry and Endodontics
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• 제37권2호
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• pp.119-122
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• 2012

Regenerative endodontics has a potential to heal a partially necrotic pulp, which can be beneficial for the continued root development and strengthening of immature teeth. For this purpose, triple antibiotic mixture of ciprofloxacin, metronidazole, and minocycline was recommended as intracanal medicament in an attempt to disinfect the root canal system for revascularization of a tooth with a necrotic pulp. However, discoloration of the tooth was reported after applying this. This case shows the idea for preventing the tooth discoloration using a delivery syringe to avoid the contact between the clinical crown and the antibiotics.

• 대한치과기공학회지
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• 제45권4호
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• pp.124-130
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• 2023

This study aims to describe the clinical experience of single and bridge crowns fabricated using a cementless screw-retained implant prosthesis system. In the case of single crown (#37), regular link (HDL) was used, and bridge crowns (#15~#24), (#26~#27), (#17~#14) (#24~#26) were fabricated by selecting regular link and short link considering the vertical height. One abutment was hex shaped to ensure that it could be mounted while preventing insertion and prosthesis rotation. The advantages of cementless implant prosthesis include shorter chair time and periodic care, strong retention with LINK abutment, safety from inflammation, bacterial infection, and complications due to peri-implant cement, and high patient satisfaction. Dentists should double-check the position of the implant fixture and dental technicians should continuously manage the fit of the link and prosthesis with digital equipment to reduce screw loosening and fractures.

• 대한치과기공학회지
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• 제9권1호
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• pp.5-19
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• 1987

The factors which impact on the productivity of medical organization are technique, manager, raw materials, management style, manpower structure, job construction, and so on. Human resources is the most important factor among them, but the productivity of serice organization can not be measured easily. The purpose of this study was to verify the effect of laboratory status, the degree of job cognition, and stress on the productivity of dantal prosthetic products, and to fine out the factors which impact on the productivity. The results were as follows: 1. The job characteristice of crown bridge laboratory part and porcelain laboratory part similar to each other. Also partial denture laboratory part and complete denture laboratory part were similar to each other. But that of orthodontic laboratory part was different from other. 2. the degree of job cognition made significant difference statisfically according to job characteristics of each dental laboratorise. 3. The correlation coefficient between job cognition of dental laboratory technician and workshop environment was.23, but the correlation between job cognition job stress appeared reversely, its coefficient was-.17. 4. The productivity of technician engaged in dental laboratory was much heigher than that of technician engaged in dental clinical laboratory room, and each were different in the degree of job cognition. 5. the most important factors which impact one the performance productivity of dental laboratory technician were the fact whether he married or not and his status.

• 대한치과기공학회지
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• 제41권2호
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• pp.93-100
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• 2019

Purpose: This study is making a dog dental prosthesis using digital dental technology. The mechanical strength of the prosthetic material was observed in terms of compressive strength and fracture pattern. Methods: The experiment was performed using dog mandibular molars. The teeth were scanned and modeled. The specimens were made of zirconia, PMMA and Ni-Cr. The specimens were subjected to a vertical compression test with an artificial cancellous bone in UTM tester. Vertical compressive strength and fracture behavior of specimen were observed. Results: The result of observing the compressive load between specimen and artificial bone were $184.8{\pm}5.7N$ in the zirconia specimen, $185.6{\pm}8.9N$ in the PMMA specimen, and $184.4{\pm}4.0N$ in the Ni-Cr alloy specimen. Compression marks of artificial bones were observed. The fracture strength of specimen was observed. The fracture strength of the zirconia specimen was an average of 1,381.4N. The fracture strength of the PMMA specimen was an average of 572.2N. Conclusion: The crown made of three kinds(zirconia, PMMA, Ni-Cr alloy) of materials has the strength to chew about the artificial bone. zirconia and PMMA have vertical compressive strength applicable to medium dog dental prosthetic materials.