Salivary Gland Stones (Sialolithiasis)
Overview
Sialolithiasis is the medical term for the formation of calcified stones (sialoliths) within a salivary gland or its duct. These stones obstruct the normal flow of saliva, leading to swelling, pain, and sometimes infection. The condition is most common in the parotid (near the ear) and submandibular (under the jaw) glands, with the latter accounting for about 80 % of cases.
Who it affects: Sialolithiasis can occur at any age but peaks in the fourth and fifth decades of life. Men are slightly more likely to develop stones than women (approximately 60 % vs. 40 %).
Prevalence: Studies estimate that 1.2 % of the general population will experience a salivary stone at some point in their lives, and it accounts for roughly 30 % of all salivary‑gland disorders that bring patients to an otolaryngology clinic.[1]
Symptoms
The presentation can range from mild discomfort to severe pain. Common symptoms include:
- Intermittent swelling of the affected gland – usually noticeable just before meals when saliva production increases.
- Painful “milking” of the gland – gentle pressure on the gland releases a small amount of saliva and may lessen discomfort.
- Recurrent “dry mouth” sensation in the area supplied by the blocked gland.
- Foul‑tasting or foul‑smelling saliva – a sign that the saliva is stagnating.
- Redness or tenderness over the gland – may become more pronounced if infection (sialadenitis) develops.
- Difficulty opening the mouth (trismus) – occurs rarely when the stone is large or the gland is inflamed.
- Visible stone – in rare cases, a hard nodule can be palpated or seen in the floor of the mouth.
- Fever, chills, or general malaise – these systemic signs suggest secondary infection and require urgent care.
Causes and Risk Factors
How stones form
Salivary stones develop when minerals (primarily calcium phosphate and calcium carbonate) precipitate around a nidus of organic material such as mucus, bacteria, or a desquamated epithelial cell. The exact cascade is not fully understood, but several mechanisms have been identified:
- Stagnant saliva – low flow creates an environment for mineral deposition.
- Altered saliva composition – higher calcium or reduced bicarbonate levels promote crystallisation.
- Obstruction from a ductal anomaly or mucous plug that initiates a “plug‑and‑grow” process.
Risk factors
- Age 30‑60 years – peak incidence.
- Male sex – modestly higher risk.
- Dehydration or reduced oral fluid intake – concentrates saliva.
- Medications that cause dry mouth (anticholinergics, antihistamines, certain antidepressants).
- History of salivary gland infection or inflammation (e.g., recurrent sialadenitis).
- Smoking – associated with changes in saliva composition.
- Systemic conditions such as hypercalcemia, gout, or Sjögren’s syndrome.
- Anatomical factors – the submandibular duct (Wharton’s duct) is longer, more tortuous, and opens against gravity, predisposing it to stone formation.
Diagnosis
Diagnosis is usually clinical, supported by imaging studies.
Clinical examination
- Palpation of the gland during a “milking” maneuver.
- Observation of swelling before and after meals.
- Inspection of the floor of the mouth for palpable stones in the submandibular duct.
Imaging studies
- Ultrasound – first‑line, non‑invasive, and detects >2 mm stones with >90 % sensitivity.[2]
- Plain radiographs (occlusal or panoramic X‑ray) – useful for radiopaque stones (≈80 % are radiopaque).
- CT scan (non‑contrast) – gold standard for small or radiolucent stones; shows exact location and size.
- MR sialography – provides a radiation‑free view of the ductal system, helpful when surgery is contemplated.
- Sialendoscopy – both diagnostic and therapeutic; a thin fiber‑optic camera is passed through the duct to visualize the stone directly.
Laboratory tests
Blood work is not routinely required unless infection is suspected (CBC, CRP) or a systemic cause (e.g., hypercalcemia) is being evaluated.
Treatment Options
Management is tailored to stone size, location, symptoms, and the presence of infection.
Conservative measures (stones ≤5 mm)
- Hydration – increase water intake to stimulate salivation.
- Sialogogues – sour candies, lemon wedges, or chewing gum to promote saliva flow.
- Warm compresses – applied to the gland for 10‑15 minutes, 3‑4 times daily, can aid spontaneous expulsion.
- Massage (“milking”) the gland – gentle upward pressure from the gland toward the mouth after meals.
- These measures resolve up to 30 % of small stones without invasive procedures.[3]
Medical therapy
- Antibiotics – indicated only if secondary bacterial sialadenitis is present (e.g., amoxicillin‑clavulanate).
- Analgesics – NSAIDs such as ibuprofen for pain and inflammation.
- Corticosteroids – short courses (e.g., prednisone 10–20 mg daily for 5‑7 days) may reduce swelling prior to a procedural attempt.
Procedural interventions
- Sialendoscopy with stone retrieval – minimally invasive; a basket or laser is used to fragment or extract the stone. Success rates exceed 90 % for stones <7 mm.[4]
- Extracorporeal shock wave lithotripsy (ESWL) – acoustic waves fragment larger stones, allowing natural passage. Often combined with sialendoscopy.
- Transoral ductal surgery – an incision in the mouth to access and manually remove stones located near the duct orifice.
- Submandibular gland excision – reserved for recurrent or large stones (>15 mm) that cause chronic infection or when the gland is non‑functional.
- Parotid gland surgery – more complex due to facial nerve proximity; used rarely, only when other methods fail.
Lifestyle & supportive measures post‑procedure
- Continue sialogogues for several weeks to keep the duct clear.
- Avoid extremely dry or sugary foods that decrease salivation.
- Maintain good oral hygiene to reduce bacterial load.
Living with Salivary Gland Stones (Sialolithiasis)
Even after successful removal, many patients benefit from habits that keep saliva flowing and reduce recurrence.
Daily management tips
- Stay hydrated – aim for at least 2‑2.5 L of water per day.
- Use sialogogues regularly – a slice of lemon or a few sour candies 2‑3 times daily, especially before meals.
- Chew sugar‑free gum after meals to stimulate flow.
- Good oral hygiene – brush twice daily, floss, and consider an antimicrobial mouth‑wash (e.g., chlorhexidine) if you have a history of infection.
- Avoid tobacco and excessive alcohol – both dry the mucosa.
- Regular dental check‑ups – dentists can spot early ductal changes.
- Monitor for swelling – keep a brief diary of any recurring gland enlargement to discuss with your doctor.
Prevention
While not all stones are preventable, risk can be lowered by adopting the following strategies:
- Maintain optimal hydration; carry a water bottle if you work in dry environments.
- Limit medications that cause xerostomia when possible; discuss alternatives with your physician.
- Manage systemic conditions that affect calcium metabolism (e.g., keep serum calcium within normal range).
- Practice good oral hygiene to minimize bacterial colonisation of the ducts.
- Consume a balanced diet rich in fruits, vegetables, and adequate calcium – paradoxically, a normal calcium intake reduces supersaturation of saliva.
- Use humidifiers in dry climates or during winter heating.
Complications
If a stone remains untreated, several problems may develop:
- Acute or chronic sialadenitis – infection of the gland, leading to pain, pus, fever, and possible abscess formation.
- Glandular atrophy – long‑standing obstruction can cause irreversible loss of salivary tissue, resulting in permanent dry mouth (xerostomia) on that side.
- Fistula formation – chronic infection may create an abnormal tract to the skin.
- Spread of infection – rarely, infection can spread to the neck spaces or even the mediastinum, a life‑threatening scenario.
- Facial nerve injury – most often a risk only when surgical removal of a parotid gland stone is attempted.
When to Seek Emergency Care
Warning signs that require immediate medical attention
- Rapidly worsening swelling of the face or neck, especially if it extends beyond the gland area.
- Severe, throbbing pain that does not improve with ibuprofen or warm compresses.
- Fever ≥ 38.5 °C (101.3 °F), chills, or feeling generally ill.
- Difficulty swallowing, breathing, or opening the mouth (trismus) that limits normal function.
- Red streaks spreading from the gland toward the jaw or neck (possible cellulitis).
- Sudden onset of drooling or inability to produce any saliva.
If you experience any of these symptoms, go to the nearest emergency department or call emergency services (e.g., 911 in the U.S.) promptly.
References
- Sialolithiasis: Review of Etiology, Diagnosis and Management. NCBI, 2014.
- Centers for Disease Control and Prevention (CDC) – Imaging Guidelines. Accessed May 2026.
- Mayo Clinic – Salivary Gland Stones (Sialolithiasis). Updated 2023.
- Cleveland Clinic – Sialolithiasis Overview. 2022.
- National Institutes of Health (NIH) – Salivary Gland Disorders. 2021.
- World Health Organization (WHO) – Oral Health Fact Sheet. 2020.