• Epithelial Plaques (localized thickenings): Found in:

  • Lateral Periodontal Cyst

  • Botryoid Odontogenic Cyst

  • Gingival Cyst of Adults

  • Glandular Odontogenic Cyst

• Radicular Cysts: Derived from Rests of Malassez.

• Impacted Canine Associations:

  • Most common odontogenic cyst: Dentigerous cyst.

  • Most common odontogenic tumor: Adenomatoid Odontogenic Tumor (AOT).

• Eruption Cyst: Considered an extra-alveolar dentigerous cyst (soft tissue counterpart).

 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.

• Bacteria adhere to acquired pellicle
• Coaggregation enables biofilm complexity
• Sucrose → lactic acid → pH drops → Hydroxyapatite dissolves

Key Enzymes Recap:

• Invertase → splits sucrose
• GTF → forms sticky glucans for adhesion
• FTF → synthesizes fructans for biofilm scaffolding

• 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).

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.