Which tooth structure is conserved more in metal bonded bridges compared to PFM bridges?

• A. Less tooth structure is conserved
• B. More tooth structure is conserved
• C. Equal amount of tooth structure
• D. No relation to tooth structure

Answer: (B)

Metal bonded bridges are designed to provide significant strength and durability, primarily due to the use of metal frameworks. This allows for a more conservative tooth preparation compared to porcelain-fused-to-metal (PFM) bridges, which require the addition of ceramic overlay.

In metal bonded bridges, the metal framework can be made thinner while still maintaining the necessary strength for function. This means less tooth structure needs to be removed for the bridge to fit correctly and provide adequate support. In contrast, PFM bridges involve the added thickness of porcelain, which necessitates more extensive tooth reduction to accommodate both the metal substructure and the porcelain overlay, leading to more tooth structure being conserved in the case of metal bonded bridges.

Thus, when comparing the two, metal bonded bridges typically conserve more natural tooth structure than PFM bridges, allowing for a more conservative approach to dental restoration.