A method and apparatus for producing a dental restoration with enhanced adhesive or bonding strength are disclosed. The dental restoration comprises a zirconia based crown and a porcelain layer built-up on a top surface of the zirconia based crown. The zirconia based crown is to be bonded to a top of an abutment toothand has dimensions that are smaller than outer dimensions of the abutment tooth. A first surface of the zirconia based crown is configured to adhere to the abutment toothand a second surface of the zirconia based crown is configured to receive the porcelain layer built-up. The first surface and the second surface of the zirconia based crown are treated with a surface treatment solution which includes at least nitric acid (HNO3), hydrofluoric acid (HF) and hydrogen peroxide (H2O2). Further, the zirconia based crown may be treated with an ultrasonic impact treatment in addition to the surface treatment of the zirconia based crown.
