Oral Health and Mumps Quiz

Salivary Gland Diseases

• Salivary gland diseases are categorized into congenital abnormalities, variations in salivary flow, infectious conditions, tumor-like conditions, autoimmune conditions, sialosis, and tumors.

Congenital Abnormalities

• Aplasia: Complete absence of one or more salivary glands, leading to xerostomia.
• Atresia: Congenital absence or blockage of salivary gland ducts, leading to xerostomia and cyst formation.
• Aberrancy: Normal salivary gland tissue developing in an abnormal location, like the Stafne bone defect.
  • Stafne Bone Defect: A part of the submandibular gland can develop within a bony cavity or depression in the mandible. Typically discovered incidentally during X-ray examination. The defect appears as a well-defined area between the premolar region and the jaw angle, below the inferior dental canal.

Variation in Salivary Flow

• Sialorrhea: Excessive salivation.
  • Etiology : possible causes include acini hypertrophy, denture wear, certain medications (pilocarpine, iodides, bromides), teething in young children, and certain metal intoxications (lead, mercury, arsenic).
• Xerostomia: Dry mouth due to decreased salivary flow.
  • Etiology: possible causes include developmental problems (aplasia, atresia), endocrine abnormalities (menopause, hypothyroidism, diabetes), vitamin deficiencies (Vitamin A, C, B12, nicotinic acid), and anemias (pernicious, iron deficiency), and medication (antihistamines, anticholinergics, opium).

Clinical Manifestation of Sialorrhea & Xerostomia

• Sialorrhea: Clinical signs include profuse salivation, metallic taste, painful and inflamed mucous membranes, and swollen salivary glands.
• Xerostomia: Clinical signs include dry mouth, burning sensation, difficulty chewing and swallowing, speech difficulties, sloughing of mucous membranes, fissured tongue with atrophy of the filiform papillae, and unpleasant taste

Infectious Conditions

• Viral:
  • Mumps (acute epidemic parotitis) : An acute, contagious viral infection transmitted by droplets, causing parotid gland swelling.
  • Cytomegalovirus inclusion disease:
  • A rare condition caused by CMV, a herpes virus. CMV can remain latent in salivary gland cells. Reactivation is possible under conditions of weakened immunity. Congenital CMV infection can cause severe damage to babies.
• Bacterial:
  • Acute bacterial sialadenitis: Acute post-operative parotitis or surgical mumps infection, caused by microorganisms. Usually due to insufficient salivary flow.
  • Chronic bacterial sialadenitis: Non-specific inflammation of major salivary glands due to ductal obstruction, leading to secondary pyogenic bacterial infection. Common cause is sialolithiasis(stone).
    • Mechanism: Sialolithiasis, a blockage of the salivary ducts by stones (calculi/sialoliths), leads to decreased salivary flow. This decreased flow creates an environment conducive to bacterial infection, which then causes chronic sialadenitis.

Sialolithiasis (Stones in Salivary Ducts)

• Etiology: Caused by calcium salt deposition, altered mucin, epithelial cells, and bacteria. Submandibular glands are particularly affected (80%).
• Factors include abnormally long, tortuous ducts (like Wharton’s duct in submandibular gland), thicker mucus secretions (rich in calcium), and possible food particle obstruction.

Clinical Picture of Sialolithiasis

• Periodic swelling and pain, especially during mealtimes, due to the release of saliva.
• In severe cases, a hard mass at the periphery of the duct can be felt.

Clinical Significance of Xerostomia

• Infections (like candidiasis) are more common, related to a lack of saliva's protective and antimicrobial actions. This can lead to oral problems like gingivitis (inflammation of the gums), periodontitis, alveolar bone loss, and rampant caries (tooth decay).
• Patients with xerostomia tend to experience annoyance and mouth-related discomfort.

Tumor-like Lesions (Necrotizing Sialometaplasia)

• A benign inflammatory reaction in the salivary gland tissue, clinically and histologically resembling a salivary gland carcinoma (cancer). The cause is frequently related to local ischemia.

Autoimmune Condition (Sjogren's Syndrome)

• A chronic, systemic autoimmune disorder causing lymphocytic infiltration and damage in the salivary glands. This results in dry mouth (xerostomia), dry eyes (xerophthalmia), and keratoconjunctivitis sicca (dry eye inflammation).

Salivary Gland Tumors

• Epidemiology: Salivary gland neoplasms are uncommon, representing a small percentage of head and neck cancers. The most common location is the parotid gland. The majority are benign.
  • Etiology: Environmental factors (alcohol, smoking, viral infections, radiation), dietary factors, and genetic factors play a role.
• Presentation: Often asymptomatic swelling. Pain is not a common initial complaint.
• Classification: Benign and malignant. Important parotid tumors: pleomorphic adenoma and Warthin's tumor (benign). Important malignant tumors: mucoepidermoid tumor, acinic cell carcinoma, and adenoid cystic carcinoma.

Diagnosis, Workup, and Imaging

• US: Initial assessment tool. Good for evaluating superficial areas, but less effective for deep-lobe conditions.
• Sialography: Gold standard for evaluating the duct system to ensure normal flow in salivary ducts and visualize any obstructions.
• CT Scan: Modality of choice for suspected inflammatory disorders, visualization of salivary duct stones, cortical bone involvement, and signs of necrosis in tumors (important for distinguishing benign from malignant, or for identifying deep-seated lesions).
• MRI: Modality of choice for palpable lesions or suspected cancers. More detail on soft tissue, useful to rule out intracranial extensions or lymph node involvement.
• PET/CT Scan: Improved staging for evaluating cancers, especially when tumors are already treated.
• Fine-Needle Aspiration Biopsy (FNAB): Screening biopsy to differentiate inflammatory cells from cancerous cells to assist diagnosis . It’s less invasive than other biopsies, allowing for detection of inflammatory cells versus malignant cells.

Treatment

• Benign parotid tumors: Often require enucleation (removal of the growth) or superficial parotidectomy (removal of part of the parotid gland). Large tumors or those affecting deeper lobes might require total parotidectomy.
• Malignant parotid tumors and submandibular tumors: Often require comprehensive surgical resection (removal) involving the entire affected tissue or gland. In some cases, wider surgical procedures (like total parotidectomy) are performed. High-grade cancers may necessitate wide surgical margins, and preservation of facial nerves is a paramount concern.

Management of the Neck

• Node-positive neck: Patients with ipsilateral (same side) lymph nodes (LN) positive for tumor: ipsilateral radical neck dissection (removal of lymph nodes on the affected side of the head and neck). If contralateral (opposite side) nodes are also affected, a contralateral modified neck dissection is performed to preserve the internal jugular vein.

Radiotherapy

• Indications: High-grade or unfavorable histology, advanced clinical stage, involvement of facial nerves, or positive margins of resection or neck nodes following surgery.
• Purpose: To prevent recurrence of tumor growth in surrounding tissues and reduce regional spread of the tumor to surrounding areas.

Chemotherapy

Role is often limited to treatment of metastatic disease or to palliative care for aggressive, loco-regional disease when surgery or radiation therapy are not appropriate treatment choices. Cisplatin is the most studied single agent for this purpose.

Molecular Targeted Therapy

• Purpose: Identify molecular abnormalities in different subtypes of salivary gland cancers allowing for targeted therapies.

Biopsy Considerations

• Fine-needle aspiration biopsy (FNAB): Provides an initial, less invasive method for screening.
• Disadvantage: Inaccurate in differentiating between certain types of tumors.

Other Considerations

• A summary of other possible treatment approaches may exist elsewhere in these notes (e.g., excisional biopsy).
• Information on special cases or complications of these procedures might also be relevant.