A raised white line running horizontally along the buccal mucosa at the occlusal plane is most likely:

Correct answer: D. Linea alba

• A. Oral submucous fibrosis presents with fibrotic bands and reduced mouth opening, not a simple white line at the occlusal plane.
• B. Leukoedema presents as a diffuse, filmy, opalescent appearance of the buccal mucosa that disappears when the mucosa is stretched — not a horizontal line at the occlusal plane.
• C. White sponge nevus is a genetic condition causing extensive white folded plaques throughout the oral mucosa, not a single horizontal line.
• D. Correct. Linea alba is a normal anatomical variant — a horizontal white line on the buccal mucosa at the level of the occlusal plane, caused by low-grade frictional pressure from the teeth. It is bilateral and not pre-malignant.