A complete denture patient has a prominent, sharp mylohyoid ridge with rigid overlying tissue. How should the mandibular denture be designed?

Correct answer: B. The lingual flange is shortened in that region

• A. Reducing the vertical dimension does not alter the contact between the flange and the ridge, and brings its own set of problems including angular cheilitis and reduced masticatory efficiency.
• B. CORRECT. A sharp mylohyoid ridge with unyielding mucosa over it cannot tolerate flange pressure — it produces a persistent, sharply localised sore spot. RELIEVING or SHORTENING the lingual flange in that region is the answer. Where retention is critically compromised, surgical reduction of the ridge is the alternative.
• C. Extending the flange increases the pressure on the very structure causing the pain and worsens it.
• D. The buccal flange has nothing to do with the mylohyoid ridge, which lies on the lingual aspect of the mandible.

Note: Balance this against the general rule that maximum extension gives maximum retention. Anatomical structures that force compromise on the mandibular denture: the mylohyoid ridge, the genial tubercles, a prominent mental foramen on a resorbed ridge, and the retromylohyoid fossa. Always relieve before you shorten — you lose less border seal.