Epithelial cysts

    Developmental odontogenic cysts
        Odontogenic keratocyst
        Dentigerous cyst (follicular cyst)
        Eruption cyst
        Lateral periodontal cyst
        Gingival cyst of adults
        Glandular odontogenic cyst (sialo-odontogenic)
        
        
    Inflammatory odontogenic cysts

        Radicular cyst (apical and lateral)
        Residual cyst
        Paradental cyst
        
    Non-odontogenic cysts

        Nasopalatine cyst
        Nasolabial cyst
    
Non-epithelial cysts (not true cysts)

    Solitary bone cyst
    Aneurysmal bone cyst

• Solitary Bone Cyst (Traumatic Bone Cyst): Usually situated above the inferior dental canal.

• Stafne's Bone Defect (Static Bone Cavity/Lingual Mandibular Bone Defect): Located below the inferior dental canal. (Note: Stafne's is a pseudocyst/developmental defect, not a true cyst).

• 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.

• Derived from Reduced Enamel Epithelium (REE):

  • Dentigerous Cyst

  • Eruption Cyst

  • Paradental Cyst

• Derived from Rests of Serres (remnants of dental lamina):

  • Odontogenic Keratocyst (OKC)

  • Gingival Cyst of Newborn

  • Gingival Cyst of Adult

  • Lateral Periodontal Cyst

  • Glandular Odontogenic Cyst

• SLE → IgG, IgM, IgA deposits at BMZ + superficial lamina propria
• Lichen Planus (Erosive/Atrophic) → Autoimmune T-cell; BMZ involvement
• Cicatricial Pemphigoid → Subepidermal blistering from anti-BMZ antibodies

• Calcifying Odontogenic Cyst (COC) / Gorlin Cyst: Characterized by Ghost Cells.

• Aneurysmal Bone Cyst (ABC): Associated with a "blood-soaked" appearance on gross examination.

• Radicular Cyst - Common Site: Maxillary anterior teeth (due to higher incidence of trauma).

• Odontogenic Keratocyst (OKC) / Keratocystic Odontogenic Tumor (KCOT):

  • Most common site: Posterior mandible (similar to ameloblastoma).

  • Expansion: Tends to expand antero-posteriorly; buccal and lingual expansion seen in late stages.

  • Basal layer histology: Tall columnar cells with palisaded nuclei – "row of tombstones" or "picket fence appearance."

  • Classification: Now considered a benign odontogenic neoplasm (KCOT) in recent WHO classifications.