• Actinomycosis (Sulfur Granules):

  • Yellow sulfur granules: Are actually bacterial colonies.

  • Histopathology: Colonies appear "cotton wool" shaped. (Note: "Cotton wool appearance" is seen radiographically in Paget's disease).

• Tuberculosis (TB):

  • Diagnosis (Gold Standard): Presence of acid-fast bacilli in sputum.

  • Staining Method: Ziehl-Neelsen staining method is used to identify acid-fast bacilli.

  • Scrofula: TB of cervical lymph nodes.

  • Lupus Vulgaris: TB of skin.

• Tongue & Gingival Appearance in Systemic Conditions:

  • Strawberry tongue and Raspberry tongue: Seen in stomatitis of Scarlet Fever.

  • Strawberry Gingivitis: Seen in Wegener's Granulomatosis.

Paget's Disease

• Chief Complaint: Denture tightening (due to arch expansion)
• Fractures: Chalk-stick fractures
• Facial Feature: Leontiasis ossea (lion-like facies)
• Radiology: Cotton wool appearance
• Histology: Jigsaw puzzle pattern
• Clinical: Bone warm to touch (↑ vascularity)
• Laboratory: ↑ Alkaline phosphatase (>250 Bodansky units)
• Other Signs: Osteoporosis circumscripta, platybasia
• Memory Aid: "Paget's Patients Prefer Tight Dentures"

Osteopetrosis

• Radiographic Sign: Rugger Jersey Spine (classic)
• Fractures: Chalk-stick fractures

Fibrous Dysplasia

• Facial Feature: Leontiasis ossea
• Histology: Chinese script pattern
• Radiology:
  • Ground glass appearance
  • Rind sign, orange peel appearance
• Bone Deformity: Hockey stick/Shepherd's crook deformity (femur)
• Key Feature: Lesional bone fused with normal bone (vs COF)
• Memory Aid: "Fibrous Faces Feel Funny"

Cemento-Ossifying Fibroma (COF)

• Histology: Chinese script pattern
• Facial Feature: Leontiasis ossea
• Difference: NOT fused with normal bone (vs Fibrous Dysplasia)

Hyperparathyroidism

• Radiology: Ground glass appearance (brown tumor)
• Histology: Numerous giant cells, vascular stroma, hemosiderin deposits

Cherubism & Central Giant Cell Granuloma

• Histology: Same as hyperparathyroidism (giant cells + vascular stroma + hemosiderin)
• Note: Cherubism previously called "Familial fibrous dysplasia"
• Memory Aid: "Giant Cells Have Three Homes" (Hyperparathyroidism, Cherubism, CGCG)

Juvenile Ossifying Fibroma

• Aggressiveness: More aggressive than Cemento-ossifying fibroma
• Types:
  • Trabecular type: Common in jaws
  • Psammomatoid type: Involves base of skull

Gemination

• Attempted division of a single tooth germ before calcification.

• Results in two crowns (complete/incomplete) with one root and canal.

• Tooth count remains normal.

• Difficult to differentiate from fusion with a supernumerary tooth.

 Twinning

• Complete division of a single tooth germ.

• Results in one normal + one supernumerary tooth.

• Tooth count is more than normal.

Fusion

• Union of two separate tooth germs.

• If before calcification → single large tooth.

• If after calcification → roots fused, crowns may be separate.

• More common in deciduous teeth.

Concrescence

• Union by cementum only.

• Occurs after root formation.

• Common in maxillary molars.

• Pioneer bacteria invade dentinal tubules before clinical signs
• Tubules contain pure forms:
  • One tubule → cocci
  • Adjacent tubule → bacilli or threads
• No mixed forms within a single tubule

• Stevens-Johnson Syndrome (SJS):

  • Characterized by ulcers with hemorrhagic crusts.

  • Typically has an acute onset following drug exposure (mainly sulfa group drugs).

• Biopsy for Vesiculobullous Pathology: Should be taken from the margin of the vesicle/bulla, including a significant amount of normal-appearing mucosa, to capture the pathological changes and adjacent healthy tissue for comparison.

• Linea Alba: A white, bilateral line on the buccal mucosa associated with pressure, frictional irritation, or sucking trauma from the facial surface of teeth.

• Morsicatio Buccarum: Chronic irritation seen on the buccal mucosa as a result of suction and glassblowers (chewing habits).

• Riga-Fede Disease: Sublingual ulcerations in infants resulting from chronic mucosal trauma from adjacent primary teeth (often natal/neonatal teeth).

Leukoplakia

• Type: Clinical term
• Histology: Hyperkeratosis ± Dysplasia

Verrucous Carcinoma

• Type: Variant of SCC
• Features:
  • Intact basement membrane
  • Parakeratin plugging
  • Broad "elephant-foot" rete ridges

Adenosquamous Carcinoma

• Features: Mixed adenocarcinoma + SCC