Kim Hyeongil, Prasad Soni, Dunford Robert, Monaco Edward A
Associate Professor, Restorative Dentistry, University at Buffalo, State University of New York, Buffalo, NY.
Assistant Professor, General Dental Sciences, Marquette University, Milwaukee, Wis.
J Prosthet Dent. 2014 Sep;112(3):606-12. doi: 10.1016/j.prosdent.2014.02.001. Epub 2014 Mar 20.
The effect of microwave brazing on the strength properties of dental casting alloys is not yet known.
The purpose of this study was to compare the strength properties of preceramic brazed joints obtained by using a microwave oven and a conventional torch flame for a high noble alloy (Au-Pd).
A total of 18 tensile bars made of an Au-Pd ceramic alloy were fabricated. Six specimens were cut and joined with a high-fusing preceramic solder in a specially designed microwave oven, and 6 specimens were joined with a conventional natural gas/oxygen torch. The remaining 6 uncut specimens were tested as a control. All the specimens were subjected to testing with a universal testing machine. A 1-way ANOVA was performed for each strength property tested.
The tensile strength of the uncut group was the highest (745 ±19 MPa), followed by the microwave group (420 ±68 MPa) and the conventional torch group (348 ±103 MPa) (P<.001); however, no significant difference in tensile strength was found between the microwave group and gas torch group. The tensile strength of the microwave group exceeded ANSI/ADA Standard No. 88, Dental Brazing Alloys (a joint standard of the American National Standards Institute and the American Dental Association).
The microwave heating preceramic solder method demonstrated the excellent tensile strength of an Au-Pd alloy and may be an alternative way of joining alloys when a torch flame is contraindicated.
微波钎焊对牙科铸造合金强度性能的影响尚不清楚。
本研究的目的是比较使用微波炉和传统火炬火焰对一种高贵金属合金（金-钯合金）进行预陶瓷钎焊所获得的接头的强度性能。
共制作了18根由金-钯陶瓷合金制成的拉伸棒。将6个试样切割后在专门设计的微波炉中用高熔点预陶瓷焊料进行连接，另外6个试样用传统的天然气/氧气火炬进行连接。其余6个未切割的试样作为对照进行测试。所有试样均使用万能试验机进行测试。对每个测试的强度性能进行单因素方差分析。
未切割组的拉伸强度最高（745±19兆帕），其次是微波组（420±68兆帕）和传统火炬组（348±103兆帕）（P<0.001）；然而，微波组和燃气火炬组之间的拉伸强度没有显著差异。微波组的拉伸强度超过了ANSI/ADA标准第88号《牙科钎焊合金》（美国国家标准学会和美国牙科协会的联合标准）。
微波加热预陶瓷焊料方法显示出金-钯合金优异的拉伸强度，并且在禁忌使用火炬火焰时可能是连接合金的一种替代方法。
