Sialolithiasis (Salivary Duct Stones)

4.06 Sialolithiasis (Salivary Duct Stones)

Presentation
Patients of any age may develop salivary duct stones. The vast majority of such stones occur in Wharton's duct from the submaxillary gland. The patient will be alarmed by the rapid swelling beneath his jaw that suddenly appears while he is eating. The swelling may be painful but is not hot or red and usually subsides within two hours. This swelling may only be intermittent and may not occur with every meal. Infection can occur and will be accompanied by increased pain, exquisite tenderness, erythema and fever. Under these circumstances pus can sometimes be expressed from the opening of the duct when the gland is pressed open.
What to do:



Bimanually palpate the course of the salivary duct, feeling for stones.



When a small superficial stone can be felt, anesthetize the tissue beneath the duct and ampule with a small amount of lidocaine 1% with epinephrine. If available, a punctum dilator can be used to widen the orifice of the duct. Then milk the gland and duct with your fingers to express the stone(s).



If the stone cannot be palpated, try to locate it with x rays. Standard x rays of the mandible are likely to demonstrate only large stones. Dental x ray film shot at right angles to the floor of the mouth is much more likely to demonstrate small stones in Wharton's duct. Place film between cheek and gum to visualize Stenson's duct.



When a stone cannot be demonstrated or cannot be manually expressed, the patient should be referred for contrast sialography and/or surgical removal of the stone. Often sialography will show whether an obstruction is due to stenosis, a stone, or a tumor.



Begin treatment of any infection with cefalexin or dicloxacillin 500mg po tid x 10 days after obtaining cultures.
What not to do:



Do not attempt to dilate a salivary duct if mumps is suspected. Acute, persistent pain and swelling of the parotid gland along with inflammation of the papilla of Stenson's duct, fever, lymphocytosis, hyperamylasemia and malaise should alert the examiner to the probability of mumps.
Discussion
Salivary duct stones are generally composed of calcium carbonate and calcium phosphate. Uric acid stones may form in patients with gout. Although the majority form in Wharton's duct in the floor of the mouth, approximately 10% occur in Stenson's duct in the cheek, and 5% in the sublingual ducts. Depending on the location and the size of the stone the presenting symptoms will vary. As a rule, the onset of swelling will be sudden and associated with salivation during a meal.