• 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.

Leukoedema

• Diagnostic Feature: Lesions do not rub off; disappear when cheek is stretched

Heck's Disease (Focal Epithelial Hyperplasia)

• Appearance: Cobblestone mucosa
• Also Seen In: Pyostomatitis vegetans, Keratosis follicularis

Infectious Mononucleosis

• Nickname: Kissing disease
• Etiology: Epstein–Barr Virus (EBV)

Trotter’s Syndrome

• Key Features: Pharyngeal pain due to nasopharyngeal carcinoma
• Associated Structures: CN V, CN IX, CN X

 Post-Herpetic Neuralgia

• Key Features: Persistent pain after Herpes Zoster, often affecting the ophthalmic division
• Associated Structures: CN V1

 Ramsay Hunt Syndrome (Herpes Zoster Oticus)

• Key Features: Facial paralysis, ear pain, vesicles, hoarseness, vertigo
• Associated Structures: Geniculate ganglion, CN VII

 Reader’s Syndrome (Para-Trigeminal Syndrome)

• Key Features: Trigeminal pain with ocular sympathetic paralysis
• Associated Structures: CN V + sympathetic fibers

 Sphenopalatine Neuralgia (Sluder’s / Horton’s / Lower Half Headache)

• Key Features: Unilateral pain in eye, maxilla, ear, mastoid, zygoma; no trigger zone; may occur at same time daily
• Associated Structures: Vidian nerve, cavernous sinus

Horner’s Syndrome

• Key Features: Triad of miosis, ptosis, anhidrosis; facial vasodilation
• Associated Structures: Sympathetic chain lesion

 Frey’s Syndrome (Auriculotemporal Syndrome)

• Key Features: Gustatory sweating during eating; flushing in temporal region
• Associated Structures: Auriculotemporal nerve (CN V3)

 Glossopharyngeal Neuralgia

• Key Features: Sharp pain in ear, pharynx, tonsil, posterior tongue; trigger zone in tonsillar fossa
• Associated Structures: CN IX

Occipital Neuralgia

• Key Features: Unilateral pain in neck and occipital region; tender spot below superior nuchal line
• Associated Structures: Cervical plexus sensory branches

 Eagle’s Syndrome (Stylohyoid Syndrome)

• Key Features: Deep dull pain in oropharynx, posterior auricular region, dysphagia, limited neck motion
• Associated Structures: Elongated styloid process or calcified stylohyoid ligament

Acute suppurative osteomyelitis

• Serious sequela of periapical infection.
• Leads to spread of pus through the medullary cavities of bone.
• Depending upon the main site of involvement of bone, can be of two types-

1. Acute intramedullary
2. Acute subperiosteal

Acute Intramedullary Osteomyelitis

CLINICAL FEATURES:

• Patient experiences dull , continuous pain , indurated swelling forms over the affected region of jaw involving the cheek , febrile.
• When mandible involved, loss of sensation occurs on lower lip on affected side due to involvement of inferior alveolar nerve.
• Teeth become loose later along with tender on percussion
• Pus discharge , trismus , foul smell , regional lymphadenopathy , weakness

RADIOGRAPHIC FEATURES

• Earliest radiographic change is that trabeculae in involved area are thin, of poor density & slightly blurred.
• Subsequently multiple radiolucencies appear which become apparent on radiograph.
• In some cases there is saucer shaped area of destruction with irregular margins.
• Loss of continuity of lamina dura, seen in more than one tooth.

HISTOLOGIC FEATURES:

• Dense infiltration of marrow by polymorphonuclear leukocytes.
• Bone trabeculae in involved site (sequestrum) are devoid of cells in the lacunae.
• separation of considerable portions of devitalized bone.

Acute Subperiosteal Osteomyelitis

CLINICAL FEATURES

• Pain , febrile condition , i/o and e/o swelling , parasthesia
• Bone involvement limited to localized areas of cortex.
• Pus ruptures rapidly through the overlying cortex, tracks along the surface of mandible under the periosteal sheath.
• Elevation of periosteum from cortex is followed eventually by minute cortical sequestration.

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

 General Features

• Caused by mutation in DSPP gene (dentin sialophosphoprotein).

• Teeth appear translucent or opalescent.

• Enamel fractures easily due to poor dentin support.

• Pulp chambers are obliterated or enlarged depending on type.

• Also called Hereditary Opalescent Dentin or Shell Teeth.

Type II DI

• Pulp chambers are normal but rapidly obliterate.

• Associated with progressive hearing loss.

Type III DI

• Pulp chambers are large and shell-like.

• Seen in Brandywine isolate population.