T/F: Sharp internal line angles are recommended.

T/F: Sharp internal line angles are recommended.

• A. True
• B. False
• C. Sometimes
• D. Not sure

Answer: (B)

Sharp internal line angles should be avoided in amalgam cavity preparations because the material is brittle and concentrates stress at any sharp corner. Rounding those angles spreads the occlusal forces more evenly, reduces the risk of crack initiation and propagation, and makes condensation of the amalgam easier to achieve a dense, void-free fill. For these reasons, sharp internal line angles are not recommended, so the statement is not correct.

Sharp internal line angles should be avoided in amalgam cavity preparations because the material is brittle and concentrates stress at any sharp corner. Rounding those angles spreads the occlusal forces more evenly, reduces the risk of crack initiation and propagation, and makes condensation of the amalgam easier to achieve a dense, void-free fill. For these reasons, sharp internal line angles are not recommended, so the statement is not correct.