Abstract: An improved porcelain fused to metal crown having a composite structure comprising layers of a bonding agent and ceramics and optionally a mixture of a bonding agent and ceramics and/or a mixture of ceramics and a porcelain, which are thermally sprayed around the metal crown, and a layer of fused porcelain formed on the above layers. The porcelain fused to the metal crown is useful for restoration of a defective tooth crown as an artificial tooth crown.

Abstract: An improved investment casting process for producing dental restorations, particularly a dental crown, comprising the steps of fixing a wax pattern onto a truncated cone in a metallic ring having a lining of a cushioning material, pouring an investment material into the space around the wax pattern in the metallic ring, drying the resultant product, melting out the invested wax pattern, curing the resultant product at a temperature of 700.degree. to 950.degree. C for 20 to 150 minutes to give a mold, fixing the mold thus obtained to a centrifugal casting machine and casting a molten chromium-cobalt and/or nickel alloy in the mold maintained at a temperature of 100.degree. to 500.degree. C.