Porcelain crowns consist of an inner metal layer and an outer ceramic coating, combining the strength of metal with the aesthetics of ceramic. They are currently the most common type of fixed dental prosthesis. In China, porcelain crowns are typically classified by the metal alloy used: cobalt-chromium alloy, nickel-chromium alloy, titanium alloy, pure titanium, and gold alloy porcelain crowns.
Nickel-chromium alloy and cobalt-chromium alloy crowns are currently widely used due to their relatively lower cost. However, nickel is a potential allergen, and some in the academic community still question the safety of its use in the oral cavity. Therefore, avoiding nickel-chromium crowns whenever possible is a reasonable choice.
Cobalt-chromium alloys are nickel-free and offer a relatively low-cost option among porcelain-fused-to-metal crowns, making them a cost-effective restorative solution.
Gold alloys exhibit excellent biocompatibility and bond better with porcelain than other metals. They offer stable color and aesthetic appeal. When financial circumstances permit, gold alloy porcelain-fused-to-metal crowns are a suitable choice.
Pure titanium possesses outstanding biocompatibility but has relatively poor bonding strength with porcelain. Therefore, its use should be approached with caution for patients with multiple missing teeth seeking porcelain-fused-to-metal restoration.