• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.4
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• pp.199-206
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• 2019

Objectives: In mandibular edentulism, the treatment option with a two-interforaminal implant-retained bridge and a removable partial denture is rarely evaluated in literature. The aim of this in vitro study was to evaluate the stress distribution of this treatment option by comparing it with traditional treatment options with interforaminal implants in the edentulous mandible. Materials and Methods: Two interforaminal implants were placed in a formalin-fixed cadaver mandible, and overdentures with three different types of attachments were fabricated: (1) two ball attachments and an overdenture, (2) a Dolder bar and an overdenture, and (3) screw-retained two-implant inter-canine porcelain fused to a metal bridge and an implant-assisted removable denture (IARD) with precision attachments. Three biting conditions were generated for each denture type, and the strains were documented under vertical loading of 100 N. Results: The calculated strain values from measured strains in all measurement sites and loading conditions for the screw-retained two-implant intercanine porcelain fused to a metal bridge and a cast framework partial denture with precision attachments situation were lower than in the other scenarios (P<0.05). Conclusion: Within the limitations of the present study, it can be concluded that an IARD may be a reasonable and valuable alternative to ball attachments or a bar in two interforaminal implants, especially when the patients prefer to be able to show their teeth even when they take out their removable dentures.

• The Journal of the Korean dental association
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• v.27 no.1 s.236
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• pp.15-18
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• 1989

"62번 보다는 좀 어둡게" 또는 "62번과 65번 사이 정도로"라는 이러한 지시들이 만족스러운 결과를 가져오는가? "선생님, 제 앞니가 이젠 너무 희고 자연스럽지 않아요. 남들이 보면 해 넣은건지 금방 알아요." Porcelain fused to metal crown은 그 심미적 장점 때문에 전치부 수복에 있어 사용이 보편화되어 왔다. 하지만 두께의 제한과 세련되지 못한 일률적인 수복물은 일반적으로 너무 밝고 흰(높은 명도와 낮은 채도) 까닭에 인공적인 것을 쉽게 식별할 수 있으며, 환자들도 하여금 보다 개성화가 요구되어 오고 있다. 이러한 심미적 요구와 함께 최근 우수한 심미성과 높은 강도의 도재전장관들, 즉 Dircor이나 Cera Pearl, Alumina 또는 Magnesia core porcelain등이 연구 개발되어 왔다. 도재 축성술에 있어서도 내장된 첨색효과(internal characterization)나 다층축성법(layer build up)등 많은 방법들이 발전되어 왔다. 자연스러운 도재관을 재현하여 주기 위해서는 먼저 자연치아의 색조에 관한 치과의사의 충분한 인식과 판단이 앞서야 한다. 인식된 색조에 대한 정보가 체계적으로 기록되어 기공사에게 전달되고 재현되어야 한다.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.3
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• pp.234-242
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• 2024

Immediate implant placement and restoration have the advantage of shortening the treatment period and maintaining aesthetics until final restoration. However, single implant restoration in the maxillary anterior region may be aesthetically difficult, and surgical trauma delivered to soft and hard tissues during implant placement may affect future aesthetic results. In order to obtain predictable results during anterior implant placement and restoration, surgery and restoration plans must consider the height of the interdental bone, characteristics of the gingiva, and morphological characteristics of the patient's teeth. In this case, we attempted to reproduce the emergence profile and stabilized soft tissue through gingiva modification and digital impression of a labially placed maxillary anterior implant in a patient who desired porcelain fused-metal (PFM) restoration due to economic issues.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.375-381
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• 2000

The conventional approach for replacing missing maxillary lateral incisors dictates the placement of either a conventional porcelain-fused-to-metal (PFM)bridge, resin-bonded fixed partial denture, or single implant prosthesis. However, several appearance-related disadvantages have been reported in the use of a prosthesis which incorporates a metal substructure. To address these limitations, metal -free restorative alternatives have been recently developed to expand the clinical options when fabrication of these prostheses is indicated. This clinical report describes the treatment of patients with a missing maxillary lateral incisor where the dentition was non-invasively restored with resin-bonded fixed partial denture(RBFPD) using In-Ceram and Targis-Vectris system.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.109-120
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• 2004

INTRODUCTION: The build-up method has been used for application of porcelain powder on the metal framework to make final tooth shape conventionally. This method takes time and need skill to mimic final shade and shape of porcelain fused to metal crown. The purpose of this study was to develop standard shape and shade laminating porcelain forms to reduce build-up time. METHODS: To make tooth form porcelain paste, several liquid organic compounds were added to conventional feldspathic porcelain. The amount of additives and rheologic property were tested to find out best composition. Comparison of mixing methods to reduced porosity, proper heating schedule, and measurement of shrinkage amount and residual organic materials were performed to set-up standard procedures. Finally, biaxial flexural strength and color of preformed laminated paste porcelain were compared with those of porcelain which fabricated by the conventional build-up method. RESULTS: There was no significant difference in physical properties and color stability between two fabrication methods after various testing methods. Conclusion: This new build-up method can be applied to fabricate the PFM crown and bridge without any loss of strength and optical properties.

• Journal of Technologic Dentistry
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• v.33 no.3
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• pp.185-192
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• 2011

Purpose: This study was to evaluate the shear bond strength of the ceramic fused to Ni-Cr alloy(Bellabond plus) and Co-Cr alloy(Wirobond C) by heat treatment. Methods: Metal specimens were divided into 5 groups for each alloy according to heat treatment conditions prior to porcelain application. Fifteen specimens from each group were subjected to a shear load a universal testing machine using a 0.1mm/min cross-head speed and one specimen from each group was observed with EDX line profile. Results: The diffusion of metal oxide observed far in the specimen heat treated than no heat treated in the opaque layer. The shear bond strength measured highest to BP3(50.50MPa), WC2(50.49MPa) groups and measured lowest from BP1(35.1MPaa), WC1(39.66MPa) groups which were not treated with heat, and there was a significant difference (p<0.05). Conclusion: The shear bond strength of Ni-Cr alloy(Bellabond plus) and Co-Cr alloy(Wirobond C) measured similar 5 groups all.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.43-46
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• 1997

The interfacial bond strength and microstructural analysis of pre-heat treated porcelain-fused-metal (PFM) were investigated using a mechanical three-point bending tester and scanning electron microscope(SEM). Four kinds of heat treated samples were prepared as follows; A: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, hold 3min under vacuum, B: heating $1200^{\circ}F\rightarrow1600^{\circ}F$ holding 1min, reheating $\rightarrow1850^{\circ}F$ under vacuum condition, C: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, holding 3min in the air, repeat same heat treatment process under vacuum condition, D: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, holding 1min in the air. The three-point bending test results shows that the interfacial bond strength of specimen B and C were higher than that of A and B. The SEM study reveals that Specimen C shows the highest surface density.

• The Journal of Korean Academy of Prosthodontics
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• v.20 no.1
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• pp.7-17
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• 1982

In order to investigate the internal adaptability and cytotoxicity for porcelain fused to metal Ni-Cr alloy, two commercial alloys (Generic Gold-R alloy, Aalba Dent- Valloy)were employed and compared with new developed beryllium free Ni-Cr alloy (KIST-K alloy). After cementation of each crown to abutment die before and after ceramic bonding respectively, dies were mounted to epoxy resin and the internal space was measured between crown and die of each point on sagittal section. The results were as follows: 1) The results show that the space between the crown and the die was largest at the incisal edge, followed by the shoulder or the bevel and chamfer. The least was to be in the axial surface. 2) There were no significant difference in the adaptability of the compared alloys. 3) On day 2 of the experiment the cell multiplication was slightly inhibited by R and K alloys. However, observations taken at day 4 and 7 showed normal cell multiplication process compared to control group. 4) Alloy V exhibited the most severe cell toxicity among the alloys tested on day 2. By day 4 and 7 it showed a decrease level in toxicity, however it did not exhibit normal cell growth as compared to control group.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.5 no.1
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• pp.34-43
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• 1996

In nowdays many dental CAD/CAM system were developed. Among those only Cerec and Celay were used globally as clinical application. Celay is a machinable ceramic system that is capable of milling inlays, onlays, and veneers from prefabricated industrial ceramic blocks(Vita Celay Blanks). The advatages of Celay are to simplify the manufactures and to save the processing time. For esthetics In-Ceram Alumina bridges were introduced into maxillary anterior restoration. They have a high strength, a high translucency and an excellent marginal adapation. But the laboratory processes are very difficult and complicated. So the construction of In-Ceram Alumina bridge combined with celay system was desgined. The patient is a 28 year old age male. The chief complain is missing of maxillary left central incisor. He wants to restore anterior bridge for esthetically. The Alumina bridge framework was constructed easily by celay system. Glass ilfiltration was occurred. After that, vitadura-${\alpha}$porcelain build up was occurred by conventional method. The translucency of In-Ceram Alumina 3 unit bridge revealed to be superior to that of porcelain fused to metal bridge. So we report it with clincal case and literature reviews.

• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.283-290
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• 2020

PURPOSE. The present study aimed to evaluate the clinical applicability of monolithic zirconia (MZ) crowns of different thickness via determination of fracture resistance and marginal fit. MATERIALS AND METHODS. MZ crowns with 0.5, 0.8, 1.0, and 1.5 mm thickness and porcelain fused to metal (PFM) crowns were prepared, ten crowns in each group. Marginal gaps of the crowns were measured. All crowns were aged with thermal cycling (5 - 55℃/10000 cycle) and chewing simulator (50 N/1 Hz/lateral movement: 2 mm, mouth opening: 2 mm/240000 cycles). After aging, fracture resistance of crowns was determined. Statistical analysis was performed with one-way ANOVA and Tukey's HDS post hoc test. RESULTS. Fracture loads were higher in the PFM and 1 mm MZ crowns compared to 0.5 mm and 0.8 mm crowns. 1.5 mm MZ crowns were not broken even with the highest force applied (10 kN). All marginal gap values were below 86 ㎛ even in the PFM crowns, and PFM crowns had a higher marginal gap than the MZ crowns. CONCLUSION. The monolithic zirconia exhibited high fracture resistance and good marginal fit even with the 0.5 mm thickness, which might be used with reduced occlusal thickness and be beneficial in challengingly narrow interocclusal space.