Biochemical structure, symptoms, location and treatment of sialoliths

Sialolithiasis is the most common disease of the salivary glands, which can cause acute and chronic infections. More than 80% of sialoliths occur in the submandibular gland or its duct, 6% in the parotid gland, and 2% in the sublingual gland or minor salivary glands. Typical symptoms are recurrent swelling and pain in the involved gland, often associated with eating, due to obstructions of the draining duct. The aim of the study was to analyze biochemical structure, symptoms, size, and location of salivary stones as well as concomitance with nephrolithiasis.

This study was conducted targeting 46 patients with sialolithiasis who visited the Department of Oral Surgery, Medical University of Lodz, Poland in 2009-2015. Medical records containing patients' age, sex, position of the salivary stone, and symptoms were collected and analyzed. Stones were examined ultrastructurally with a scanning electron microscope and X-ray diffractometer.

Multiple stones were found in 1% of patients. We observed that men had sialolithiasis about twice as often as women. The chemical structure of the stones varied but they mainly contained different traces of carbon, calcium, oxygen, phosphorus, and sulfur. Longitudinal sections of the stones revealed elongated, round, and irregular shapes. We noticed that nephrolithiasis was present in 11 (24%) patients. We observed the unilateral location of sialoliths with multilayer structures, mainly composed of inorganic material, such as hydroxyapatite.

We found that the location of the stones influenced the symptoms, and concomitance of sialoliths and nephroliths was common.