From the Guidelines
Sialolithiasis is primarily caused by the formation of calcified stones within the salivary glands or their ducts, often as a result of dehydration, decreased salivary flow, and changes in salivary pH. The development of these stones can be attributed to the accumulation of calcium salts around a nidus of debris, such as mucus plugs, bacterial colonies, or cellular debris 1. Several factors contribute to stone formation, including:
- Dehydration
- Decreased salivary flow
- Changes in salivary pH
- Salivary stasis
- Ductal inflammation Certain medications, such as anticholinergics, antihistamines, and some antidepressants, can increase the risk of sialolithiasis by reducing saliva production. Additionally, smoking, poor oral hygiene, and chronic sialadenitis are also risk factors. Systemic conditions like gout, diabetes, and autoimmune disorders may predispose individuals to sialolithiasis. The submandibular gland is most commonly affected, accounting for 80-90% of cases, due to its unique anatomy and the composition of its saliva 1. Stones typically cause pain and swelling in the affected gland, especially during meals when saliva production increases but cannot flow past the obstruction.
The clinical presentation of sialolithiasis often involves intermittent pain, characteristically occurring just before eating, and associated tenderness of the involved salivary gland 1. Bimanual palpation may enable the stone to be palpated, and imaging and ultrasound can be useful diagnostic tools. Referral to oral/maxillofacial surgeons is often indicated for further management.
It is essential to note that the submandibular gland's tortuous duct anatomy and the more viscous, alkaline saliva it produces make it more prone to stone formation 1. Understanding the causes and risk factors of sialolithiasis can help guide diagnosis and treatment, ultimately improving patient outcomes in terms of morbidity, mortality, and quality of life.
From the Research
Sialolithiasis Causes
- Sialolithiasis is a major cause of salivary gland dysfunction, and its mechanism for stone formation is incompletely understood 2.
- The condition is frequently encountered in clinical practice, and it is one of the most common problems that afflict the salivary glands 2.
- Sialoliths are the underlying cause of salivary gland obstructive disease in 60%-70% of cases 3.
Location and Composition of Sialoliths
- Sialoliths are more frequently located in the submandibular gland (84%), than in the parotid gland (13%) 4.
- The majority of the submandibular stones are located in Wharton's duct (90%), whereas parotid stones are more often located in the gland itself 4.
- Salivary stones consist of an amorphous mineralised nucleus, surrounded by concentric laminated layers of organic and inorganic substances, including hydroxyapatite, carbonate apatite, whitlockite, and brushite 4.
Consequences of Untreated Sialolithiasis
- If left untreated, sialolithiasis can result in chronic sialadenitis and glandular atrophy 5.
- Larger stones may interfere with the flow of saliva and cause pain and swelling 5.
Treatment Options
- Treatment for sialolithiasis has undergone significant changes since the 1990s, with a focus on minimally invasive and gland-preserving treatment modalities 6.
- Extracorporeal shock-wave lithotripsy (ESWL), refinement and extension of methods of transoral duct surgery (TDS), and in particular diagnostic and interventional sialendoscopy (intSE) are substantial parts of the new treatment regimen 6.
- Combining different treatment modalities can further increase the effectiveness of therapy, as has been especially evident with the combined endoscopic-transcutaneous approach 6.