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Tomotake Y, Ishida O, Kanitani H, Ichikawa T. Immediate implant-supported oral rehabilitation using a photocurable plastic skull model and laser welding. A technical note on the screw-retained type: Part 1. INT J PROSTHODONT 2002; 15:303-6. [PMID: 12066496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
PURPOSE This article describes a new procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus. MATERIALS AND METHODS Preoperatively, the framework was fabricated on a photocurable resin skull model produced from a CT scan and individually designed guide template. The implants were immediately placed using the guide template; laser welding connected the components of framework. RESULTS Despite the custom-made prosthesis, the total treatment from implant placement to superstructure placement can be completed within only 1 day. CONCLUSION This procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus may be useful for any implant system and patient.
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MESH Headings
- Dental Articulators
- Dental Implantation, Endosseous/instrumentation
- Dental Implantation, Endosseous/methods
- Dental Implants
- Dental Prosthesis, Implant-Supported
- Dental Soldering/methods
- Denture Design
- Denture Retention
- Denture, Partial, Fixed
- Denture, Partial, Immediate
- Follow-Up Studies
- Humans
- Jaw, Edentulous/diagnostic imaging
- Jaw, Edentulous/rehabilitation
- Jaw, Edentulous/surgery
- Lasers
- Mandible/diagnostic imaging
- Mandible/surgery
- Models, Anatomic
- Patient Care Planning
- Plastics
- Skull
- Time Factors
- Tomography, X-Ray Computed
- Treatment Outcome
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Iglesia MA, Moreno J. A method aimed at achieving passive fit in implant prostheses: case report. INT J PROSTHODONT 2001; 14:570-4. [PMID: 12066705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
PURPOSE The aim of this article is to describe a technique that attempts to solve titanium-related problems while affording passive fit. MATERIALS AND METHODS The method basically involves the manufacture of a cast titanium framework fitted onto titanium machined abutments. After verifying the passive fit of the framework presoldered to the abutments, Nd-YAG laser welding is completed in the laboratory. RESULTS The aim of the technique is to secure the following clinical benefits: (1) use of titanium, as it is the best-suited material; (2) use of high-precision machined abutments; (3) laser welding and its advantages; and (4) achievement of passive fit. CONCLUSION The technique described is adequate to achieve passive fit in implant prostheses using titanium and laser welding.
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Li H, Chen Y, Li Y, Zhao Y, Fu Q, Yang T. [Effects of laser welding on ceramic fused to metal]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2001; 32:271-3. [PMID: 12600105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
OBJECTIVE This study was aimed to investigate the bonding effect of laser welding on ceramic fused to metal. METHODS Ten laser welded CW-PA ceramo-alloy rods were fused with porcelain at fusion zone. The porcelain-metal bond strength was measured with pull-through test. SEM examination and EDAX analysis were performed. Ten non-welded CW-PA ceramo-alloy pull-rod plates were used as comparison. RESULTS The results showed that the bond strength of laser welded sample was 41.32 +/- 6.69 MPa, approaching to 45.71 +/- 9.98 MPa of the non-welded sample (P > 0.05). The microscope displayed the interface compacted union of the two phase boundary. There was no change in the elements and their ratio at the fusion zone. CONCLUSION These results indicate that laser welding does not affect ceramic fused to metal.
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Bertrand C, Le Petitcorps Y, Albingre L, Dupuis V. The laser welding technique applied to the non precious dental alloys procedure and results. Br Dent J 2001; 190:255-7. [PMID: 11303685 DOI: 10.1038/sj.bdj.4800942] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
AIM The laser welding technique was chosen for its versatility in the repair of dental metal prosthesis. The aim of this research is to assess the accuracy, quality and reproducibility of this technique as applied to Ni-Cr-Mo and Cr-Co-Mo alloys often used to make prosthesis METHOD The alloy's ability to weld was evaluated with a pulsed Nd-Yag Laser equipment. In order to evaluate the joining, various cast wires with different diameters were used. The efficiency of the joining was measured with tensile tests. In order to understand this difference, metallographic examinations and X-Ray microprobe analysis were performed through the welded area and compared with the cast part. RESULTS It was found that a very slight change in the chemistry of the Ni-Cr alloys had a strong influence on the quality of the joining. The Co-Cr alloy presented an excellent weldability. A very important change in the microstructure due to the effect of the laser was pointed out in the welding zone, increasing its micro-hardness. CONCLUSION The higher level of carbon and boron in one of the two Ni-Cr was found to be responsible for its poor welding ability. However for the others, the maximum depth of welding was found to be around 2mm which is one of the usual thicknesses of the components which have to be repaired.
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Ford T. Heat-activated solderless passivation--the alternative to soldering. Interview by Arun K. Garg. DENTAL IMPLANTOLOGY UPDATE 2001; 12:1-6. [PMID: 11993142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Wiskott HW, Doumas MT, Scherrer SS, Susz C, Belser UC. Microstructures of brazings and welds using grade 2 commercially pure titanium. INT J PROSTHODONT 2001; 14:40-7. [PMID: 11842903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
PURPOSE Microstructural analyses of commercially pure titanium (CpTi) are scarce. The present report presents the micrographs, fractographs, elemental characteristics, and hardness profiles of brazed joints and weldments using machined rods of CpTi. MATERIALS AND METHODS CpTi rods were joined using four techniques: laser welding, electric-arc welding, electron-beam welding, and gold- and Ti-filler brazing. The specimens were then subjected to tensile and fatigue loading. After sectioning and patterning, optical micrographs of intact joints were obtained. Fractured surfaces were investigated using scanning electron microscopy (SEM). The joint's composition was determined by SEM-energy dispersive x-ray analysis. Hardness was determined at specific locations using a microindenter. RESULTS While laser welding left the parent metal's equiaxed structure fairly intact, electric-arc welding, electron-beam welding, and brazing created a heat-affected zone in the vicinity of the joint. The extent and characteristics of the heat-affected zone depended on the amount of heat transferred to the specimens. In this respect, brazing essentially increased grain size and altered their shape. Electron-beam welding augmented this phenomenon, yielding grains that encompassed the full diameter of the joint. Electric-arc welding disrupted the granular pattern and generated highly lamellar/acicular structures. CONCLUSION Hardness was not a good indicator of mechanical resistance, nor was the joint's structural continuity with the parent substrate. Still, acicular microstructures were characterized by a peculiar behavior in that such joints were highly resistant to tensile stresses while their fatigue strength ranged among the lowest of the joints tested.
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Romero GG, Engelmeier R, Powers JM, Canterbury AA. Accuracy of three corrective techniques for implant bar fabrication. J Prosthet Dent 2000; 84:602-7. [PMID: 11125345 DOI: 10.1067/mpr.2000.111494] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
STATEMENT OF THE PROBLEM Numerous articles emphasize the importance of passivity of implant-prosthetic component interfaces. Nonpassive interfaces can lead to bone loss, abutment fracture, and connecting screw breakage. PURPOSE The purpose of this study was to evaluate 3 postcasting techniques for the correction of non-passive fit between a cast bar superstructure and its interface with an implant abutment. MATERIAL AND METHODS Thirty implant Hader bars were fabricated based on a metal model composed of two 3.8/4.5 HL PME titanium implant abutments. Initial measurements were collected on the y-axis of the left implant abutment-bar interface by using a M2001ARS toolmaker microscope. Means were calculated from buccal, distal, and lingual measurements on each specimen. Ten specimens were sectioned, indexed, and corrected by casting the same alloy (group 1). Ten specimens were sectioned, indexed, and corrected by soldering (group 2). The last 10 specimens were submitted to 2 cycles of electrical discharge machining on a MedArc M-2 EDM machine (group 3). Postcorrection measurements were collected on the 3 groups. A 1-way ANOVA and a Tukey-Kramer test at a 0.05 significance level were performed on the 3 groups after the corrective techniques. RESULTS Initial gap means were 192 microm for group 1, 190 microm for group 2, and 198 microm for group 3. There was a significant difference (P<0.05) in gap means between group 1 (15 microm) and group 2 (72 microm) as well as between group 2 and group 3 (7.5 microm) after each correction technique. No difference was detected between group 1 and group 3. CONCLUSION The electrical discharge machining group resulted in the smallest mean gap distance of 7.5 microm, thus meeting the criteria of passive fit (within 10 microm) described in the literature.
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Li H, Li M, Zhao Y, Meng X. [Study of accuracy of one-piece casted and laser welded bridges]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2000; 18:112-5. [PMID: 12539345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To assess whether laser welded bridge be fit for the clinical usage, this study compares the accuracy of laser welded multi-unit bridges with one-piece casted bridges. METHODS A precise stainless mold which was 20 mm length composed of two abutments (one premolar and one molar) and one pontic (two missed teeth) was made. 5 wax patterns of four-unit FPD frame-works in one-piece casting based on the mold were made. After that, they were invested with inner (Bellavest) and outer investment (phosphate and gypsum). Then they were casted with CW-PA (Ni-Cr-Nb) alloys. The other 5 wax patterns of four-unit FPD frameworks were invested and casted in two halves. Each couple of frameworks were ultra-sonic washed in distilled water and inserted to the standard metal FPD mold accurately. Laser welding machine (DL-2002) was used to weld each couple of frameworks at 305V, 20 ms. Both groups of specimens were tested on their mesiodistal span dimensions and the diameters of alloy crowns. Then they were inserted to their original stainless mold, where the marginal fitness was examined. RESULTS 1. The one-piece casted fixed multi-unit bridge couldn't be inserted to abutments completely because of distortion, while the laser welded bridge could be inserted to abutments completely. The average marginal opening of laser welded bridges was about 74 microns and conformed to clinical standard of fitness. 2. Mesiodistal dimensions of one-piece casted bridges at the inner, bottom and top margins were 19.5600 +/- 0.3877 mm, 41.2206 +/- 0.4140 mm, 41.0598 +/- 0.3379 mm respectively; while those of laser welded bridges were 20.2950 +/- 0.1191 mm, 41.9625 +/- 0.0788 mm, 42.0584 +/- 0.1089 mm, which were obviously close to metal abutments (P < 0.05). 3. The alloy crowns' diameters of one-piece casted bridges were examined as following, the premolar: phi IJ = 9.8386 +/- 0.0567 mm, phi LK = 9.9596 +/- 0.0548 mm, the molar: phi EF = 11.7948 +/- 0.0252 mm, phi HG = 11.9412 +/- 0.0763 mm; The alloy crowns' diameters of laser bridges were as following, the premolar: phi IJ = 9.7927 +/- 0.0636 mm, phi LK = 9.9438 +/- 0.0726 mm, the molar: phi EF = 11.8287 +/- 0.0863 mm, phi HG = 11.8893 +/- 0.1049 mm. There was no significant difference between the two groups (P < 0.05). CONCLUSION Laser welding greatly improve the fitness of multi-unit fixed bridges.
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Li H, Fu Q, Zhao Y, Shu X, Pan Y. [Stress-corrosion test of laser welded ceramic alloys]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2000; 18:116-8. [PMID: 12539346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE The corrosion properties of dental material are very critical. This study is to investigate the corrosion properties of laser welded basemetalalloys. METHODS The precise stainless rod molds had been made in size of phi 3 mm x 4 mm, with which 20 wax patterns were made. They were invested with inner investment (Bellavest) and outer investment (phosphate and gypsum). Then they were casted with CW-PA (Ni-Cr-Nb) alloys. All casted alloy rods were ultra-sonic washed in distilled water. Every two rods were contacted longitudinally by a special welding jig. Laser welding machine (DL-2002) was used to weld them at 305 V, 20 ms. The specimens were divided into 2 groups as following: 1. The group of stress-corrosion: 5 laser welded samples were subjected to the stress-corrosion test under 261.44 MPa in the 37 degrees C artificial saliva for 3 months in a special stress-corrosion test jig. After that, the ultimate tensile strength (UTS) was tested, the surface microcrack at the fusion zone (FZ), the heat affecting zone (HAZ) and the interface zone was observed with SEM (ARMY-1845, USA), the elements were also analyzed with EPMA (ARMY-1845, USA) at the fusion zone (FZ), the parent metal zone and the interface zone. 2. The other 5 laser welded samples were made as the controlled group. No special treatment were done to them, and the UTS was also tested, the surface of the micro crack and the elements at the FZ, the HAZ, parent metal zone and the interface zone were observed and analyzed with SEM, EPMA as well. RESULTS The study showed us that the UTS of the stress-corrosion group was 502.48 +/- 12.49 MPa, while that of the controlled group was 446.05 +/- 82.50 MPa, there was no significant difference (P > 0.05). There was no microcrack on any sample's surface at the FZ, the HAZ and the interface zone. The main elements of the FZ were Ni(56.63%), Cr(19.36%), Nb (6.57%), Si(6.01%), Al(0.32%) and Mo(11.11%), while the elements of the parent metal zone were Ni(60.77%), Cr (20.59%), Nb(5.03%), Si(3.95%), Al(0.37%) and Mo(9.29%) respectively. CONCLUSION The results suggest that the corrosion properties of laser welded alloys are excellent.
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Li H, Zhao Y, Li M. [Comparative study of technique of laser welding ceramo-alloy by different gap distance]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 2000; 35:102-4. [PMID: 11780474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the quality of laser welded non-precious base alloy by different gap distance and its clinic probability. METHODS Laser welded ceramo-alloy CW-PA specimens by different gap distance of 0.0 mm, 0.25 mm, 0.5 mm, Tested joined sample's UTS, microhardness; took SEM examination on its tensile fracture surface and metallographic examination on longitudinal cross section. RESULTS The study showed that UTS of Laser welded CW-PA by different gap distance of 0.0 mm, 0.25 mm, 0.5 mm is (446.05 +/- 82.50) MPa, (485.97 +/- 62.35) Mpa, (503.32 +/- 65.79) MPa respectively, approach to original rod (421.53 +/- 21.78) MPa (P > 0.05). Microimage at tested samples of gap distance at 0.0 mm, 0.25 mm are good. CONCLUSION It revealed that 1. Laser welding specimen should be contacted as close as possible 2. The gap distance should be less than 0.5 mm, 0.25 mm is better, and easy to handle.
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Yao S, Ying K, Li Z, Shen L. [Development and clinical application of dental spot weld & heat-treat tri-uses device]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 1999; 23:207-238. [PMID: 12583063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A spot weld & heating treatment tri-uses device based on modern mechanical-electric technique, was developed for dental spot weld, stainless steel orthodontic wire heating-reversion and Ni-Ti orthodontic wire heating-overload metamorphism. The device will be very helpful instrument in orthodontic clinic. The paper not only described the operating methods of the device, but also discussed the Performance-improved principles of stainless steel orthodontic wire and the principles of heating overload metamorphism of Ni-Ti orthodontic wire.
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Lu J, Guo T, Wang B. [The study on mechanical properties of laser welds of titanium in dentistry]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1999; 34:120-2. [PMID: 11834178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To explore the mechanical properties of laser welds of titanium under different conditions. METHODS Home-made Nd: YAG laser welding apparatus was used to weld TA2 and Ti-6Al-4V under different laser energy. Instron universal testing machine was adopted to measure the tensile load, 0.2% yield load and absolute elongation. The fractured surface was observed under SEM, Vickers microhardness values at welding area were measured and the mechanical properties after immersion in artificial saliva were detected. RESULTS The mechanical strength of laser welds were related with material, voltage and the combination of them. At 700V-750V, there was no significant difference between tensile load of TA2 laser welds and that of the original material. For Ti-6Al-4V, At 750V. The mechanical strength of laser welds before and after immersion in artificial saliva made no statistic difference. CONCLUSION It is suggested that the heat-affected zone of laser welding might be small and the corrosion resistance in artificial saliva might be high. The mechanical strength of titanium laser weld might meet the clinical demands at 19-20J/P.
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Ortorp A, Linden B, Jemt T. Clinical experiences with laser-welded titanium frameworks supported by implants in the edentulous mandible: a 5-year follow-up study. INT J PROSTHODONT 1999; 12:65-72. [PMID: 10196830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
PURPOSE The purpose of this study was to report the 5-year clinical performance of implant-supported prostheses with laser-welded titanium frameworks and to compare their performance with that of prostheses provided with conventional cast frameworks. MATERIALS AND METHODS On a routine basis, a consecutive group of 824 edentulous patients were provided with fixed prostheses supported by implants in the edentulous mandible. In addition to conventional gold-alloy castings, patients were at random provided with 2 kinds of laser-welded titanium frameworks. In all, 155 patients were included in the 2 titanium framework groups. A control group of 53 randomly selected patients with conventional gold-alloy castings was used for comparison. Clinical and radiographic 5-year data was collected for the 3 groups. RESULTS All followed patients still had fixed prostheses in the mandible after 5 years. The overall cumulative success rates were 95.9% and 99.7% for titanium-framework prostheses and implants, respectively. The corresponding success rates for the control group were 100% and 99.6%, respectively. Bone loss was 0.5 mm on average during the 5-year follow-up period. The most common complications for titanium frameworks were resin or tooth fractures, gingival inflammation, and fractures of the metal frames (10%). One of the cast frameworks fractured and was resoldered. Loose and fractured implant screw components were few (< 1%). CONCLUSION Even though the cast frameworks had a higher success rate, the overall titanium framework treatment result was well in accordance with the result of the control group. The test groups performed better after clinicians had gained some experience with the technique, and laser-welded titanium frameworks seem to be a viable alternative to conventional castings in the edentulous mandible.
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Li H, Xiao M, Zhao Y. [Dental welding titanium and its clinical usage]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 1998; 15:303-5, 310. [PMID: 12553259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Due to its excellent biocompatibility, desirable chemical and mechanical properties, Titanium has been used for implant denture, RPD and FPD, where welding techniques were indispensable. This paper introduces 5 useful modern ways to weld Titanium and their clinical usage. They are: laser, plasma welding, TIG, infraned brazing and Hruska electrowelding.
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Chaves M, Vermilyea SG, Papazoglou E, Brantley WA. Effects of three soldering techniques on the strength of high-palladium alloy solder joints. J Prosthet Dent 1998; 79:677-84. [PMID: 9627897 DOI: 10.1016/s0022-3913(98)70075-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
STATEMENT OF PROBLEM Little information is available on the optimum technique for soldering high-palladium alloys, which have gained considerable popularity for prosthodontic applications. PURPOSE The objective of this study was to compare the flexural stress at the proportional limit of four noble dental alloy specimens soldered with torch, oven, and infrared-techniques. MATERIALS AND METHODS The high-palladium alloys studied were Legacy XT (Jelenko), Freedom Plus (Jelenko), and IS 85 (Williams/Ivoclar). A gold-palladium alloy, Olympia (Jelenko), served as the control. Thirty round bars, 18 x 3 mm, were cast from each alloy, cut in half, aligned, and joined using Olympia Pre solder (Jelenko) for the gas-oxygen torch and the infrared technique and Alboro LF solder (Jelenko) for the oven technique. Each soldered bar was subjected to three-point bending, and the maximum elastic stress or strength of the solder joint was calculated at the proportional limit. Data were analyzed by two-way ANOVA and the Ryan-Einot-Gabriel-Welsch (REGW) multiple range test at the 0.05 level of significance. RESULTS There was no significant difference between torch and oven-soldering, but both were significantly different from the infrared technique. ANOVA showed a significant difference between alloys, but this difference could not be detected with the REGW test. SEM examination of the fracture surfaces revealed grooves associated with the path of crack propagation. X-ray energy-dispersive spectroscopic analysis failed to detect copper in the solders, and there were no significant changes in the solder compositions after the melting procedures. CONCLUSIONS All three techniques can yield satisfactory solder joints in high-palladium alloys. These joints should be well-polished to achieve optimal strength.
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Yu H, Du C, Cao Y. [Shear bond test of HF acid etching machinable porcelain bonded to enamel with different concentration and disposing time]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 1998; 16:169-71. [PMID: 12214428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
After HF acid etching under 5 different HF concentrations and 6 exposing times, shear bonding strength of porcelain to enamel were tested. The results showed that HF acid etching technique had a positive influence on the bonding strength of porcelain to enamel. The most favorable concentration-time groups were 2.5%-5.0 min, 5.0%-5.0 min, 7.5%-2.5 min, 10.0%-1.0 min, 15.0%-0.5 min, and the debonding type of porcelain-resin-enamel composite body was mixed debonding.
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Taylor JC, Hondrum SO, Prasad A, Brodersen CA. Effects of joint configuration for the arc welding of cast Ti-6Al-4V alloy rods in argon. J Prosthet Dent 1998; 79:291-7. [PMID: 9553882 DOI: 10.1016/s0022-3913(98)70240-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
STATEMENT OF PROBLEM Titanium and its alloys are more commonly used in prosthodontics and welding has become the most common modality for their joining. Studies on the welding of titanium and its alloys have not quantified this value, though its importance has been suggested. PURPOSE This study compared the strength and properties of the joint achieved at various butt joint gaps by the arc-welding of cast Ti-6Al-4V alloy tensile bars in an argon atmosphere. MATERIAL AND METHODS Forty of 50 specimens were sectioned and welded at four gaps. All specimens underwent tensile testing to determine ultimate tensile strength and percentage elongation, then oxygen analysis and scanning electron microscopy. RESULTS As no more than 3 samples in any group of 10 actually fractured in the weld itself, a secondary analysis that involved fracture location was initiated. There were no differences in ultimate tensile strength or percentage elongation between specimens with weld gaps of 0.25, 0.50, 0.75, and 1.00 mm and the as-cast specimens. There were no differences in ultimate tensile strength between specimens fracturing in the weld and those fracturing in the gauge in welded specimens; however, as-cast specimens demonstrated a higher ultimate tensile strength than welded specimens that fractured in the weld. Specimens that fractured in the weld site demonstrated less ductility than those that fractured in the gauge in both welded and as-cast specimens, as confirmed by scanning electron microscopy examination. The weld wire showed an oxygen scavenging effect from the as-cast parent alloy. CONCLUSIONS The effects of the joint gap were not significant, whereas the characteristics of the joint itself were, which displayed slightly lower strength and significantly lower ductility (and thus decreased toughness). The arc-welding of cast titanium alloy in argon atmosphere appears to be a reliable and efficient prosthodontic laboratory modality producing predictable results, although titanium casting and joining procedures must be closely controlled to minimize heat effects and oxygen contamination.
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Wiskott HW, Macheret F, Bussy F, Belser UC. Mechanical and elemental characterization of solder joints and welds using a gold-palladium alloy. J Prosthet Dent 1997; 77:607-16. [PMID: 9185054 DOI: 10.1016/s0022-3913(97)70103-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE This study was conducted to determine whether newer infrared or laser welding technologies created joints superior to traditional furnace or torch soldering methods of joining metals. It was designed to assess the mechanical resistance, the characteristics of the fractured surfaces, and the elemental diffusion of joints obtained by four different techniques: (1) preceramic soldering with a propane-oxygen torch, (2) postceramic soldering with a porcelain furnace, (3) preceramic and (4) postceramic soldering with an infrared heat source, and (5) laser welding. MATERIAL AND METHODS Mechanical resistance was determined by measuring the ultimate tensile strength of the joint and by determining their resistance to fatigue loading. Elemental diffusion to and from the joint was assessed with microprobe tracings. Scanning electron microscopy micrographs of the fractured surface were also obtained and evaluated. RESULTS Under monotonic tensile stress, three groups emerged: The laser welds were the strongest, the preceramic joints ranged second, and the postceramic joints were the weakest. Under fatigue stress, the order was as follows: first, the preceramic joints, and second, a group that comprised both postceramic joints and the laser welds. Inspection of the fractographs revealed several fracture modes but no consistent pattern emerged. Microprobe analyses demonstrated minor diffusion processes in the preceramic joints, whereas significant diffusion was observed in the postceramic joints. CLINICAL IMPLICATIONS The mechanical resistance data conflicted as to the strength that could be expected of laser welded joints. On the basis of fatigue resistance of the joints, neither infrared solder joints nor laser welds were stronger than torch or furnace soldered joints.
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Sakurai Y, Kawada E, Oda Y. Soldering strength of post-soldering of palladium-based metal-ceramic alloys. THE BULLETIN OF TOKYO DENTAL COLLEGE 1997; 38:95-103. [PMID: 9566126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To evaluate the post soldering of metal-ceramic alloys that have palladium as their main component, palladium-based metal-ceramic alloys with different compositions were used to assess soldering strength. Four palladium-based metal ceramic alloys were selected: Pd-Cu system, Pd-Ag system, Pd-Ni system, and Pd-Sb system, and gold-silver-palladium alloy was also used. As soldering materials, 12 k gold solder and 16 k gold solder were used. After post-soldering by butt joint samples that had been heat treated (equivalent to the porcelain firing cycle), soldering strength was evaluated by measuring the flexural strength. The yield strength had a range of 300 to 800 MPa, and the ultimate strength was in the range of 350 to 1,000 MPa; the Pd-Ag type showed the highest value. There was no correlation between the yield strength of the metal-ceramic alloys and that of the soldering samples. When the soldering strength of 12 k gold solder and 16 k solder were compared, the samples soldered with 12 k gold solder showed higher values in all cases. Samples in which heating was prolonged for 10 seconds had a high strength, within 100 to 500 MPa in yield strength and 100 to 800 MPa in ultimate strength.
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Neo TK, Chai J, Gilbert JL, Wozniak WT, Engelman MJ. Mechanical properties of titanium connectors. INT J PROSTHODONT 1996; 9:379-93. [PMID: 8957877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The tensile mechanical properties of welded titanium joints were studied, and intact titanium was used as controls. Welded joints were fabricated with either a stereographic laser-welding technique or a gas tungsten arc welding technique. The effect of heat treatment following a simulated porcelain application was also investigated. Heat-treated laser welds had significantly lower ultimate tensile strengths. Heat treatment had no effect on the modulus of elasticity or elongation, but generally significantly decreased the yield strength of the titanium specimens. The gas tungsten are welding specimens had significantly higher yield strengths and elastic moduli than the other two groups. The elongation of the control specimens was significantly greater than the elongation of the gas tungsten arc welding specimens, which was in turn significantly higher than that of the laser-welded specimens.
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Abstract
OBJECTIVE Finding an optimal soldering system for a titanium prosthesis has become increasingly important with the successful introduction of titanium and titanium alloys to dentistry. This study examined the effect of corrosion on the strength of the soldered joints of pure titanium and Ti-6Al-4V alloys joined using various solders. METHODS Commercially pure titanium and Ti-6Al-4V alloy rods (2 mm in diameter; 25 mm long) were soldered in an argon atmosphere using four solders: two kinds of titanium-based solder, a gold-based solder, and a silver-based solder. Tensile strengths were examined before or after immersion treatments. Specimens were immersed in either a 0.9% NaCl or 1.0% lactic acid solution held at 35 degrees C for 3 and 8 wk. The amounts of various metal elements released were determined by atomic absorption photospectroscopy. The natural potentials and potentiodynamic polarization behavior of the soldered specimens in 0.9% NaCl or 1.0% lactic acid were determined by a computer-assisted corrosion measurement system. The results were analyzed by ANOVA and Student's t-test. RESULTS The cp-titanium and Ti-6Al-4V samples soldered with titanium-based solders exhibited tensile strengths of 300-400 MPa and were not significantly affected by immersion in either solution (no significant difference at p < 0.05). The strengths of both the cp-titanium and titanium alloy specimens soldered with gold-based solder were significantly lower than for any of the other specimens and were affected by immersion in the 0.9% NaCl solution (p < 0.01). The cp-titanium and Ti-6Al-4V specimens that were soldered with titanium-based solders did not show any transpassive regions or breakdown in the natural electrode potential range. On the contrary, the specimens soldered with gold-based and silver-based solders showed transpassive regions or breakdown potentials at less than 0 mV in 0.9% NaCl solution. SIGNIFICANCE It is recommended that titanium-based solder be employed for titanium and titanium alloys.
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Gawlik JA, Mathieu GP, Hondrum S. The effects of tack welding and increasing surface area on the tensile strength of silver electric and flame soldered stainless steel joints. Pediatr Dent 1996; 18:215-8. [PMID: 8784912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The purposes of this study were: 1) to compare silver solder joint strength using flame and electric soldering techniques, and 2) to determine the effect of tack welding and increasing metal-to-metal contact area prior to tack welding, on the tensile strength of silver solder joints. Six methods: (flame soldered; tack welded and flame soldered; increased contact area, tack welded, and flame soldered; electrosoldered; tack welded and electrosoldered; and increased contact area, tack welded, and electrosoldered) were used to produce 15 solder joints in each group. The tensile strength of the joints were tested with Instron Universal Testing Machine. Flame soldering resulted in joints with significantly higher tensile strength (P < or = 0.001). Tack welding had no significant effect on the tensile strength of the joints. Increasing the contact area had no significant effect on the tensile strength of tack welded electric soldered joints, but significantly weakened the flame soldered joints (P < or = 0.05).
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Berger RP. A study of solder investment setting expansion and thermal contraction: Part 2. JOURNAL OF DENTAL TECHNOLOGY : THE PEER-REVIEWED PUBLICATION OF THE NATIONAL ASSOCIATION OF DENTAL LABORATORIES 1996; 13:38-41. [PMID: 9516272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, which won the NBC Fellowship Project, the author measured expansion and contraction in two soldering and six casting investments to determine which are most accurate (defined as marginal gap less than 50 micrometers and lack of movement with alternating finger pressure) under a number of manipulated parameters, including water/powder ratio, setting time, span length and burnout temperature. It was determined that all investments demonstrated slight expansion between initial and final set. Substantial contraction occurred in all investments when subjected to heat. Vestra, CB-30 and Cera-Fina demonstrated the greatest contraction at 1500 degrees F. Hi-Heat (soldering), Quick Set, High Span, Vivest, and Hi-Temp (casting) demonstrated greatest contraction at 2000 degrees F. The purpose of the study and the methods and materials used were explained in part one, published in March. The results and conclusions are presented here. An introduction to elevated fixturing and a verification of the study results will be presented in part three.
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Neurohr JH. A technique for verifying the accuracy of a soldered prosthesis with intraoral records. COMPENDIUM OF CONTINUING EDUCATION IN DENTISTRY (JAMESBURG, N.J. : 1995) 1996; 17:308-10, 312. [PMID: 9051960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The art of soldering dental ceramic alloys has always been one of the many challenges faced by the dental technologist. This article presents a method for verifying the accuracy of a postsoldered prosthesis as it relates to intraoral indexes taken before a soldering procedure. The advantage of this technique to the dentist is saved chair time. It eliminates the extra appointments that would be necessary were something to go wrong during the soldering procedure.
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Berger RP. A study of solder investment setting and thermal contraction: Part 1. JOURNAL OF DENTAL TECHNOLOGY : THE PEER-REVIEWED PUBLICATION OF THE NATIONAL ASSOCIATION OF DENTAL LABORATORIES 1996; 13:29-34. [PMID: 9516268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, which won the NBC Fellowship Project, the author measured expansion and contraction in two soldering and six casting investments to determine which are most accurate (defined as marginal gap less than 50 micrometers and lack of movement with alternating finger pressure) under a number of manipulated parameters, including water/powder ratio, setting time, span length and burnout temperature. It was determined that all investments demonstrated slight expansion between initial and final set. Substantial contraction occurred in all investments when subjected to heat. Vestra, CB-30 and Cera-Fina demonstrated the greatest contraction at 1500 degrees F. Hi-Heat [corrected] (soldering), Quick Set, High Span, Vivest, and Hi-Temp (casting) demonstrated greatest contraction at 2000 degrees F. The purpose of the study and the methods and materials used are explained in part 1. The results and conclusions will be presented in part 2. An introduction to elevated fixturing and a verification of the study results will be presented in part 3.
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