What is the maximum amount of unsupported porcelain allowed in dental restorations?

The maximum amount of unsupported porcelain allowed in dental restorations is 2 mm. This guideline is based on the understanding that unsupported porcelain can be prone to fracture under occlusal forces. When porcelain is not adequately supported by underlying structures, such as metal or dentin, it is less resilient and more susceptible to chipping or breaking.

Two millimeters is seen as a practical limit that balances aesthetic considerations with the functional demands placed on dental restorations. At this thickness, the porcelain has enough structural integrity to withstand the mechanical forces of chewing while still allowing for a visually appealing restoration.

Options indicating a thickness less than 2 mm would not provide optimal strength, leaving the restoration at higher risk for failure. Choosing a thickness greater than 2 mm may increase the likelihood of aesthetic concerns without providing significant additional strength. Hence, 2 mm is the established maximum for unsupported porcelain in restorations to ensure both durability and appearance.