Calculus Composition

• Brushite: More common in mandibular anterior
• Magnesium whitlockite: More common in posterior
• Ca:P ratio: Higher subgingivally
• Mineralization: 50% in 2 days, 60 – 90% in 12 days

Microbiology

• First colonizers: S. salivarius and S. mitis
• Red complex: P. gingivalis, T. denticola, T. forsythia (cause BOP)
• Growth enhancement: P. gingivalis grows better with succinate (C. ochracea) and protoheme (C. rectus)

Pellicle Structure

• Basal layer: Thin, difficult to remove
• Globular layer: 1 μm thick, easier to detach

Bacterial Recognition

• Gram positive: Activate TLR2 → IL – 8
• Gram negative: Activate TLR4 → TNF – α

Classification and Function

Collagenases

• MMP-8 (Neutrophil Collagenase): Most abundant in GCF
• MMP-1 (Interstitial Collagenase): Targets type I collagen

Gelatinases

• MMP-2 (Gelatinase A): 72 kDa enzyme
• MMP-9 (Gelatinase B): 92 kDa enzyme, neutrophil-derived

Bone Destruction

• Most Potent Destroyer: Interleukin-1β (IL-1β)
• Mechanism: Stimulates osteoclast activity and inhibits osteoblast function
• Clinical Relevance: Target for anti-inflammatory therapy

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.

🧪 GERD & Barrett’s Esophagus

🧫 Peptic Ulcer

• Commonest site: Duodenal bulb (1st part)
• Most frequent complication: Hemorrhage
• Best residual H. pylori test: Urea breath test
• Treatment for Zollinger – Ellison syndrome: PPI

ANUG (Acute Necrotizing Ulcerative Gingivitis)

• Signs: Punched – out crater depressions of interdental papilla
• Symptoms: Metallic foul taste, pasty saliva
• Treatment: 3 visits (2nd visit: 1 – 2 days after 1st; 3rd visit: 5 days after 2nd)

NUG/NUP

• No pocket formation (destroys junctional epithelium)

Primary Herpetic Gingivostomatitis

• Cellular change: Ballooning degeneration → Tzanck cells
• Treatment:
  • Within 3 days: Acyclovir 15 mg/kg × 5 times × 7 days
  • After 3 days: Supportive care with NSAIDs

Leukemic Gingivitis

• Most common in acute monocytic leukemia

Lead Intoxication

• Steel gray linear pigmentation (Burton's line)