Which radiographic projection is particularly useful for demonstrating a SIALOLITH in the submandibular gland or duct?

Correct answer: C. Lateral oblique

• A. A LATERAL CEPHALOMETRIC film is a standardised skull view for orthodontic and skeletal analysis, with both sides superimposed — unsuitable for localising a unilateral salivary stone.
• B. A BITEWING captures only the crowns and crestal bone of the posterior teeth — far too limited a field to include the submandibular region.
• C. CORRECT. The LATERAL OBLIQUE projection images the body and ramus of the mandible free of superimposition from the opposite side and is well suited to demonstrating a calcified SIALOLITH in the submandibular gland or its duct. A mandibular OCCLUSAL film taken with reduced exposure is the other classic view, since it profiles a stone in the floor of the mouth along the course of Wharton duct.
• D. The WATERS view is designed for the MAXILLARY SINUSES and orbital floor, projecting the petrous ridges below the sinus floors. It is not a submandibular projection.

Note: Remember that roughly 80–90% of salivary stones arise in the SUBMANDIBULAR system, because Wharton duct runs uphill against gravity and the secretion is more mucinous and alkaline. Around 20% are radiolucent and will not appear on plain films — if clinical suspicion is high and radiographs are negative, ultrasound or sialography is the next step. The classic history is pain and swelling at mealtimes.