Like A Rock

Question: A 32 year old male is evaluated for recurrent swelling under his left jaw.  Examination reveals a palpable, hard mass in the left floor of mouth.  CT is obtained that demonstrates a 5 mm stone in the distal left Wharton’s duct.  What percentage of salivary gland stones in the submandibular gland are radioopaque?

[Answer will be posted with next week's new question]

Answer to last week's question, "Toothache" (March 12, 2018)

Epithelial rest of Malassez.