Which material offers higher strength and reliable bonding?

• A. Lithium disilicate
• B. Feldspathic porcelain
• C. Zirconia
• D. Resin composite

Answer: (A)

In indirect restorations, you want a material that is both strong and can bond reliably with adhesive protocols. Lithium disilicate fits that need well. It’s a glass-ceramic with crystalline lithium disilicate that delivers high flexural strength and good fracture resistance, making it suitable for posterior crowns and other load-bearing restorations. It also bonds well when you follow proper adhesive steps: etch the surface with hydrofluoric acid to create micromechanical retention, rinse, and apply a silane coupling agent to promote strong chemical bonding with resin cements. This combination of durable strength and dependable bonding gives it an advantage over other options.

Feldspathic porcelain, while esthetic and capable of bonding nicely, doesn’t offer the same strength, so it’s more limited in posterior, high-load areas. Zirconia is extremely strong but bonding is more variable and requires specialized primers and surface treatments, which can make bonding less predictable with standard protocols. Resin composites bond well to tooth structure but generally don’t achieve the same long-term strength and wear resistance as lithium disilicate for indirect restorations.