Regular PFM is handmade by dental technician by casting. The artistic skill of the dental laboratory technologist creating the crown or bridge will determine its strength, marginal fit and esthetic appeal.
In this method a wax pattern of tooth crown or bridge is made, surrounding this pattern with an investment material, letting this harden, then melting wax and burning out the wax to produce an intricate and accurate mold was conceived. The next step involved is melting the metal and pouring it into the cavity. After cooled down, prepared product is removed from investment, finishing, sand blasting and polished.
In this casting method, there are chances of casting errors like porosity, metal shrinkage after casting, voids and sometimes errors may be due to improper wax pattern handling.