Abstract: Disclosed is a method for producing dental prostheses of the dental porcelain fused to metal type, in particular, the temperatures employed to fire and cool the prostheses are disclosed with a new tempering temperature disclosed during cool down. The tempering temperature is preferably the temperature with approximately the maximum rate of crystallization out of the glass phase of the feldspathic dental porcelain.A furnace is also disclosed having a heatable firing chamber, a firing platform, a firing platform socket, and control means that include a means for positioning the platform and adjusting the temperature. The furnace control means is programmed by a keyboard feeding a microcomputer, which controls separate programmable elements to control the furnace.