• Journal of Welding and Joining
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• v.33 no.2
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• pp.40-46
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• 2015

This study was performed to investigate the effect of ultrasonic nano crystal surface modification (UNSM) on residual stress mitigation after Weld Inlay repair for butt dissimilar metal weld with Alloy 82/182 in reactor vessel In/Outlet nozzle. As-welded and Weld Inlay specimens were made in accordance with design standard of ASME Code Case N-766, and two planes of their weld specimens were peened by the optimum UNSM process condition. Peening characteristics for weld specimens after UNSM treatment were evaluated by surface roughness and Vickers hardness test. And, residual stress for weld specimens developed from before and after UNSM treatment was measured and evaluated by instrumented indentation technique. Consequently, it was revealed that the mitigation of residual stress in weld metal after Weld Inlay repair of reactor vessel In/Outlet nozzle could be possible through UNSM treatment.

• Journal of Technologic Dentistry
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• v.28 no.2
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• pp.367-373
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• 2006

This study was performed to observe the flow change of the inlay waxes at various temperatures. The flow of inlay waxes was tested according to the treatment conditions, for 10 minutes at 40$^{\circ}C$, 41$^{\circ}C$, 42$^{\circ}C$, 43$^{\circ}C$, 44$^{\circ}C$, and 45$^{\circ}C$ The flow of inlay waxes at various temperatures was measured with an electro dial gauge. The results were as fellows: 1. The flow change of the inlay waxes at various temperatures was shown to increase in the order of wax A, B, D, C. 2. Wax A was close to ADA specification with 3% flow at 40$^{\circ}C$ and 71% flow at 45$^{\circ}C$, but wax B and D did not reach up to ADA specification with 40% flow at 45$^{\circ}C$. 3. Wax C came up with 3% flow at 40$^{\circ}C$ and 7% flow at 45$^{\circ}C$, and it revealed a very low flow change at 5$^{\circ}C$.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.135-147
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• 1994

This study was conducted to evaluate whether the fatigue toughness of visible light cured composite resins could be improved and how much percentage of polymerzation shrinkage could be affected by additional heat treatment. 7 materials were investigated for this study: P-50, Lite-fil CR inlay, Pekafil, Clearfil CR inlay, Clearfil photo posterior, Z -100 and Progress. Diametral tensile strengths and linear shrinkages of composite resins were taken under visible light cured and additional post-cure heated condition and compared each other. A fatigue toughness of above materials was evaluated by measuring diametral tensile strength after they were repeatedly loaded with 120kgf/$cm^2$ up to 3000 cycles. The results obtained were as follows : 1. When composite resins were cured just by visible light, Lite fil CR inlay, Z -100 and Progress showed respectively higher diametral tensile strength than the other materials. Clearfil CR inlay, Clearfil photo posterior and Progress exhibited strong fatigue toughness compared to P-50 and Pekafil. 2. Post-cure heat treated composite resins had higher diametral tensile strengths than visible light cured composite resins at fatigue toughness test as well as no fatigue toughness test. 3. When Composite resins were additionally polymerized by post-cure heat treatment, P-50 showed weak fatigue toughness, on the contrary, Clearfil CR inlay, Z-100, Progress showed strong one. 4. When composite resins were cured just by visible light, percentage of polymerization linear shrinkage was the lowerest in Clearfil CR inlay, followed by, in ascending order, Clearfil photo posterior, Lite-fil CR inlay, Progress, Pekafil, P-50, and Z-100. In the case of post- cure heat treated composite resins, percentage of linear shrinkage was the lowest in Clearfil photo posterior, followed by, in ascending order, Lite-til CR inlay, Clearfil CR inlay, Progress, P-50, Pekafil and Z-100. 5. Percentage of polymerization linear shrinkage was greater in the post-cure heat treated composite resins than in the visible light cured composite resins and linear shrinkage increased significantly in Pekafil, Clearfil CR inlay, and Clearfil photo posterior between at the visible light cured and at the post-cure heat treated condition. The above results is saying that additional post-cure heat treatment on the composite resins for posterior restoration is able to affect on improvement of strength and fatigue toughness and lead to increase polymerization of composite resins.

• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.184-190
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• 2018

PURPOSE. To analyze stress distribution in premolars restored with inlays or onlays using various materials. MATERIALS AND METHODS. Three-dimensional maxillary premolar models of abutments were designed to include the following: 1) inlay with O cavity (O group), 2) inlay with MO cavity (MO group), 3) inlay with MOD cavity (MOD group), and 4) onlay (ONLAY group). A restoration of each inlay or onlay cavity was simulated using gold alloy, e.max ceramic, or composite resin for restoration. To simulate masticatory forces, a total of 140 N static axial force was applied onto the tooth at the occlusal contact areas. A finite element analysis was performed to predict the magnitude and pattern of stresses generated by occlusal loading. RESULTS. Maximum von Mises stress values generated in the abutment teeth of the ONLAY group were ranged from 26.1 to 26.8 MPa, which were significantly lower than those of inlay groups (O group: 260.3-260.7 MPa; MO group: 252.1-262.4 MPa; MOD group: 281.4-298.8 MPa). Maximum von Mises stresses generated with ceramic, gold, and composite restorations were 280.1, 269.9, and 286.6 MPa, respectively, in the MOD group. They were 252.2, 248.0, 255.1 MPa, respectively, in the ONLAY group. CONCLUSION. The onlay design (ONLAY group) protected tooth structures more effectively than inlay designs (O, MO, and MOD groups). However, stress magnitudes in restorations with various dental materials exhibited no significant difference among groups (O, MO, MOD, ONLAY).

• Archives of Craniofacial Surgery
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• v.10 no.1
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• pp.55-60
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• 2009

Purpose: For blowout fracture of the medial orbital wall, the goals of treatment are complete reduction of the herniated soft tissue and anatomic reconstruction of the wall without surgical complications. Surgeons frequently worry about damage to the optic nerve from the dissection, when the part over the posterior ethmoidal foramen was fractured. The authors performed small incision and inlay grafting for reconstruction of medial orbital wall fracture. Methods: Between January 2007 and April 2008, 15 out of 32 patients were included in an analysing the outcome of corrected medial orbital wall fracture. In 15 patients of posterior comminuted fracture of medial orbital wall, insertion of porous polyethylene($Medpor^{(R)}$ channel implant, Porex, USA) to ethmoidal sinus was performed in multiple layer, through the transconjunctival approach (inlay grafting). Results: In all cases, the orbital bone volume was reconstructed in its normal anatomical position. The associated ocular problems disappeared except for mild enophthalmos in 2 patients and there were no surgical complications associated with inlay grafting. Conclusion: The advantage of inlay grafting include anatomical reconstruction of the orbital wall; the avoidance of optic nerve injury; the simplicity of the procedure; and consequently, the absence of surgery-related complications. This technique is presented as one of the preferred treatments for posterior comminuted fracture of medial orbital wall.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.384-408
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• 1994

The purpose of this study was to evaluate the fracture resistance of tooth restored with gold inlay. A profound understanding of the isthmus width factor, which is one of the several parameters of cavity designs, would facilitate the appropriate cavity preparation in a specific clinical situation. In this study, the cavities for gold inlay were prepared in maxillary left first premolar. A three-dimensional model was designed using I-DEAS program. The model was composed of 2515- nodes and 2172 isoparametric brick elements. In the model isthmus width was varied into 1/4, 1/3 and 1/2 of intercuspal width respectively, and numeric values of the material properties of enamel, dentin and gold was set. Three types of load : concentrated load, divided load and distributed load was 500N. The empty cavities in the model were also examined using divided load and distributed load. The three - dimensional Finite Element Method was used to analysis the displacement and stress distribution. The results were as follows : 1. All of the experimental models which were filled with gold inlay revealed similar direction of displacement to that of the natural tooth model under the same load type. But in the models with empty cavities, as the isthmus width increased, the degree of displacement increased in the case of divided load type. 2. All experimental models which were filled with gold inlay showed stress concentration at load points, but in the models with empty cavities at divided load type, as isthmus width increased, stress was concentrated at the comer of the pulpal floor. 3. In the models with empty cavities at divided load type, tooth fracture was expected regardless of isthmus width, but all experimental models which were filled with gold inlay after cavity preparation were not susceptible to fracture. 4. In all experimental models which were filled with gold inlay after cavity preparation, displacement patterns were similar under both concentrated and divided load types. In the models with empty cavities, a divided load resulted in a bucco-lingual cuspal displacemenat in both sides, but a distributed load resulted in a lingual displacement of the tooth.

• The Journal of the Korean dental association
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• v.25 no.1 s.212
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• pp.13-17
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• 1987

• The Journal of the Korean dental association
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• v.19 no.12 s.151
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• pp.989-991
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• 1981

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.366-374
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• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.8 no.1
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• pp.5-9
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• 1978

The purpose of this study is to investigate the effect of dental restorations on the periodontal and periapical tissues. The author examined 620 cases of amalgam, 390 cases of gold inlay, 422 cases of crown and 644 cases of bridge through the standard intraoral films being appended in the charts that had been kept at the Dept. of Oral Diagnosis in Seoul National University Hospital. This study obtained the following results; 1. The restorations of amalgam, gold inlay crown and bridge were found more frequently in female than in male. 2. The restorations of amalgam, gold inlay and crown were found more numerously in mandibular teeth than in maxillary teeth in both sexes. But in the case of crown, the fact is quite the reverse especially in anterior teeth. 3. On the contrary, in the case of bridge, the restorations of bridge were much more distributed in the maxillary teeth than in the mandibular teeth. 4. Roentgenographic changes of periodontal tissues whose teeth were treated with any type of four restorations were periodontal space widening, lamina dura discontinuity and periapical lesion in the order described in both sexes. 5. On the occasion of between amalgam and gold inlay or between crown and bridge, the differences of periodontal changes were of no consequence. On the other hand, the differences of periodontal changes were apparant between the group of amalgam & gold inlay and the group of crown & bridge.