What type of metal alloy is typically used to fabricate the metal framework of a removable partial denture (RPD)?

Correct answer: A. Base metal alloy (cobalt-chromium)

• A. CORRECT. RPD frameworks are predominantly made from cobalt-chromium (Co-Cr) base metal alloys. Co-Cr offers the ideal combination of high rigidity (stiffness), strength, biocompatibility, corrosion resistance, and low density — allowing thin, strong clasps and connectors. It is the industry standard for cast RPD frameworks.
• B. Titanium is biocompatible and used for implants, but is difficult to cast into thin RPD frameworks due to its high melting point and reactivity.
• C. Precious metal (gold) alloys can be used but are rarely used for RPDs today due to cost and lower rigidity compared to Co-Cr.
• D. Stainless steel is used for preformed bands and pediatric crowns but is not cast into custom RPD frameworks.