Wilson's disease is an autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene, resulting in impaired biliary copper excretion and toxic copper accumulation in tissues.

Pathophysiology

• Basic defect: Decreased biliary copper excretion due to defective ATP7B protein
• Mechanism: Impaired incorporation of copper into ceruloplasmin and reduced copper transport into bile
• Result: Copper accumulation in liver, brain, cornea, and other organs

Clinical Manifestations

Hepatic (Most common initial presentation)

• Acute hepatitis
• Chronic hepatitis
• Cirrhosis
• Fulminant hepatic failure

Neurological

• Movement disorders (tremor, dystonia, chorea)
• Psychiatric symptoms (depression, psychosis, behavioral changes)
• Dysarthria and dysphagia
• Cognitive impairment

Ophthalmologic

• Kayser-Fleischer rings (pathognomonic copper deposits in Descemet's membrane)
• Sunflower cataracts

Other Features

• Renal tubular acidosis
• Hemolytic anemia
• Arthritis
• Cardiomyopathy (rare)

Diagnostic Workup

• Serum ceruloplasmin: Usually decreased (<20 mg/dL)
• 24-hour urine copper: Elevated (>100 μg/24h)
• Hepatic copper content: Gold standard (>250 μg/g dry weight)
• Ophthalmologic examination: Slit-lamp for Kayser-Fleischer rings
• Genetic testing: ATP7B gene mutations
• Brain MRI: "Face of giant panda" sign in severe cases

Treatment

Chelation Therapy

• D-penicillamine: First-line, may worsen neurological symptoms initially
• Trientine: Alternative chelator, better tolerated neurologically
• Tetrathiomolybdate: For neurological presentations

Zinc Therapy

• Zinc acetate/sulfate: Blocks copper absorption, maintenance therapy
• Preferred for asymptomatic patients and maintenance

Stage 1: Initial Lesion

• 2 – 4 days after plaque accumulation

Stage 2: Early Lesion

• Timeline: 4 – 7 days after plaque accumulation
• T – lymphocyte dominance

Stage 3: Established Lesion

• Characteristic: Plasma cells and B – lymphocytes dominance

Bleeding on Probing (BOP)

• Appears earlier than visual signs
• Absence = good negative predictor of attachment loss

Gingivitis

Gingivitis is an inflammatory condition of the gingiva that can progress through several distinct stages. Understanding these stages is crucial for dental professionals in diagnosing and managing periodontal disease effectively. This lecture will outline the four stages of gingivitis, highlighting the key pathological changes that occur at each stage.

I. Initial Lesion

• Characteristics:
  • Increased Permeability: The microvascular bed in the gingival tissues becomes more permeable, allowing for the passage of fluids and immune cells.
  • Increased GCF Flow: There is an increase in the flow of gingival crevicular fluid (GCF), which is indicative of inflammation and immune response.
  • PMN Cell Migration: The migration of polymorphonuclear leukocytes (PMNs) is facilitated by various adhesion molecules, including:
    • Intercellular Cell Adhesion Molecule 1 (ICAM-1)
    • E-selectin (ELAM-1) in the dentogingival vasculature.
• Clinical Implications: This stage marks the beginning of the inflammatory response, where the body attempts to combat the initial bacterial insult.

II. Early Lesion

• Characteristics:

  • Leukocyte Infiltration: There is significant infiltration of leukocytes, particularly lymphocytes, into the connective tissue of the junctional epithelium.
  • Fibroblast Degeneration: Several fibroblasts within the lesion exhibit signs of degeneration, indicating tissue damage.
  • Proliferation of Basal Cells: The basal cells of the junctional and sulcular epithelium begin to proliferate, which may be a response to the inflammatory process.

• Clinical Implications: This stage represents a transition from initial inflammation to more pronounced tissue changes, with the potential for further progression if not managed.

III. Established Lesion

• Characteristics:

  • Predominance of Plasma Cells and B Lymphocytes: There is a marked increase in plasma cells and B lymphocytes, indicating a more advanced immune response.
  • Increased Collagenolytic Activity: The activity of collagen-degrading enzymes increases, leading to the breakdown of collagen fibers in the connective tissue.
  • B Cell Subclasses: The B cells present in the established lesion are predominantly of the IgG1 and IgG3 subclasses, which are important for the immune response.

• Clinical Implications: This stage is characterized by chronic inflammation, and if left untreated, it can lead to further tissue destruction and the transition to advanced lesions.

IV. Advanced Lesion

• Characteristics:

  • Loss of Connective Tissue Attachment: There is significant loss of connective tissue attachment to the teeth, which can lead to periodontal pocket formation.
  • Alveolar Bone Loss: Extensive damage occurs to the alveolar bone, contributing to the overall loss of periodontal support.
  • Extensive Damage to Collagen Fibers: The collagen fibers in the gingival tissues are extensively damaged, further compromising the structural integrity of the gingiva.
  • Predominance of Plasma Cells: Plasma cells remain predominant, indicating ongoing immune activity and inflammation.

• Clinical Implications: This stage represents the transition from gingivitis to periodontitis, where irreversible damage can occur. Early intervention is critical to prevent further progression and loss of periodontal support.

Desquamative Gingivitis

• Characteristics: Desquamative gingivitis is characterized by intense erythema, desquamation, and ulceration of both free and attached gingiva.
• Associated Diseases:
  • Lichen Planus
  • Pemphigus
  • Pemphigoid
  • Linear IgA Disease
  • Chronic Ulcerative Stomatitis
  • Epidermolysis Bullosa
  • Systemic Lupus Erythematosus (SLE)
  • Dermatitis Herpetiformis

• Blood transfusion: Always consider FNHTR first for fever during transfusion
• G6PD deficiency: Heinz bodies are pathognomonic; estrogen is safe
• BMT infections: HSV earliest, interstitial pneumonitis at 7 weeks
• Prevention: Patient education and prophylaxis are crucial in all three conditions

Epithelial Turnover Rates in Oral Tissues

Epithelial turnover is a critical process in maintaining the health and integrity of oral tissues. Understanding the turnover rates of different epithelial types in the oral cavity can provide insights into their regenerative capabilities and responses to injury or disease.

Turnover Rates of Oral Epithelial Tissues

1. Junctional Epithelium:

   • Turnover Rate: 1-6 days
   • Description:
     • The junctional epithelium is a specialized epithelial tissue that forms the attachment between the gingiva and the tooth surface.
     • Its rapid turnover rate is essential for maintaining a healthy seal around the tooth and for responding quickly to inflammatory changes or injury.

2. Palate, Tongue, and Cheeks:

   • Turnover Rate: 5-6 days
   • Description:
     • The epithelial tissues of the hard palate, tongue, and buccal mucosa (cheeks) have a moderate turnover rate.
     • This relatively quick turnover helps maintain the integrity of these surfaces, which are subject to mechanical stress and potential injury from food and other environmental factors.

3. Gingiva:

   • Turnover Rate: 10-12 days
   • Description:
     • The gingival epithelium has a slower turnover rate compared to the junctional epithelium and the epithelium of the palate, tongue, and cheeks.
     • This slower rate reflects the need for stability in the gingival tissue, which plays a crucial role in supporting the teeth and maintaining periodontal health.

Clinical Significance

• Wound Healing:

  • The rapid turnover of the junctional epithelium is particularly important in the context of periodontal health, as it allows for quick healing of any disruptions caused by inflammation or mechanical trauma.

• Response to Disease:

  • Understanding the turnover rates can help clinicians anticipate how quickly tissues may respond to treatment or how they may regenerate after surgical procedures.

• Oral Health Maintenance:

  • The varying turnover rates highlight the importance of maintaining good oral hygiene practices to support the health of these tissues, especially in areas with slower turnover rates like the gingiva.