Caries

1- Enamel caries

Dentin caries

Dentin caries (beaded dentinal tubules)

Dentin caries (liquifaction foci)

Dentin caries (Transverse cleft)

Test your self

Pulpitis

1- Focal reversible pulpitis(Pulp hyperaemia)

2- Acute pulpitis

3- Chronic open ulcerative pulpitis

4- Chronic open hyperplastic pulpitis (pulp polyp)

Periapical

1-Acute periapical abscess

• Histopathology: • Pus

3- Periapical granuloma

• Differential diagnosisRadicular cystChronic periapical abscessPeriapical scar

Foam cells

Chlosterol clefts

Russel and pyronine bodies

Cyst

Dentigerous cyst

• Cause:Developmental odontogenic cyst created by accumulation

of fluid between reduced enamel epithelium and crown of unerupted\impacted tooth after complete enamel formation• Differential diagnosis:

Odontogenic keratocyst – COC• Complication:

Mucoepidermoid carcinomaFeatures: Epithelium (2-4 layers / dentin beside it - associated with unerupteted tooth)

Odontogenic keratocyst

• Cause: It arises from reduced enamel epithelium and remnants of dental lamina

• Differential diagnosis:• Dentigerous cyst – COC• Aneurysmal bone cyst – Cherubism - Hyperparathyroidism • Features: Tomb stone – keratin – daughter cyst - multilocular

radiolucency extending from body to ramus – May be Associated with unerupted teeth

Eruption cyst

• Cause: It arises from reduced enamel epithelium and remnants of dental lamina

• Features: • Children on ridge• Associated with erupted tooth• No x-ray

Gingival cyst of newborn

• Cause: Arise from remnants of dental lamina.• Found on the alveolar mucosa of newborn or

children.• No x-ray

Gingival cyst of adult

• Cause: Arise from remnants of dental lamina.• Features: • Gingiva or interdental papilla of adult• No x-ray.

Lateral periodontal cyst

• Cause:Arises from remnants of dental lamina or reduced enamel epithelium.• Features: • Age: 30 years Site: Mandibular canine – premolar• Radiolucency located laterally on the root of vital tooth.• Differential diagnosis:

Radicular cyst Odontogenic keratocyst

• Histopathology: • Lining is formed of stratified squamous epithelium• Clear cells

COC

• Cause: It arises from reduced enamel epithelium and remnants of dental lamina• Features: • Age: 2nd & 3rd decade • Site: Maxilla = Mandible (more in incisor-canine region)• unilocular radiolucency• Cotton wool• May be associated with impacted tooth (mostly canine).• Differential diagnosis

Dentigerous cyst -Odontogenic keratocyst - Paget• Histopathology: • Ameloblast-like cells• Stellate reticulum like cells• Ghost cells• Dentinoid

Radicular cyst

• • Cause: Inflammatory odontogenic cyst occur in pre-

existing granuloma or secondary to pulpal infection caused inflammation and proliferation of epith rests of Malassez related to root of non-vital tooth

• Differential diagnosisLateral periodontal cystPeriapical granulomaChronic periapical abscessPeriapical scar

Anuerysmal bone cyst

• Cause:Injury & hemorrhage followed by failure of clot

formationConsequence of enucleation of true cyst

• Histopathology: • Cavity filled with unclotted blood• Multinucleated giant cells• Differential diagnosis:• Cherubism - hyperparathyrodism

Traumatic Bone cyst

• Well defined radiolucency (scalloped) between the roots teeth.

• Located above mandibular canal.

Stafne’s defect(Static bone cyst)

• Histopathology: • Normal submandibular salivary gland tissue

Nasopalatine duct cyst

• Histopathology: • Pseudostratified columnar ciliated epithelium

(respiratory epithelium)• Features: • Heart-shaped x-ray• Differential diagnosis:• Globulomaxillary cyst

Globulomaxillary cyst

• Histopathology: • Pseudostratified columnar ciliated epithelium

(respiratory epithelium)• Features: • Inverted pear-shaped between upper lateral

and canine.• Differential diagnosis:• Nasopalatine duct cyst

Cervical lymphoepithelial cyst

• Histopathology: • Pseudostratified columnar ciliated epithelium

(respiratory epithelium)• Capsule contains lymphoid tissue• Features: • Lateral side of neck• Soft tissue

Thyroglossal duct cyst

• Histopathology: • Pseudostratified columnar ciliated epithelium

(respiratory epithelium)• Capsule contains thyroid tissue• Features: • Midline of neck• Soft tissue

Dermoid cyst

Osteomyelitis

Acute suppurative osteomyelitis

• Histopathology: • Sequestrum with empty lacunae• Pus in bone marrowDifferential diagnosis: Chronic suppurative osteomyelitis

Chronic suppurative osteomyelitis

• Histopathology: • Sequestrum with empty lacunae• Granulation tissue in bone marrow• Mosaic appearanceDifferential diagnosis: Acute suppurative osteomyelitis

Chronic focal sclerosing osteomyelitis

• Histopathology: • Dense bone• Granulation tissue in bone marrowDifferential diagnosis: Diffuse sclerosing osteomyelitisPaget

Diffuse sclerosing osteomyelitis

• Histopathology: • Dense bone• Granulation tissue in bone marrowDifferential diagnosis: Chronic focal sclerosing osteomyelitisPaget

Garre’s osteomyelitis

• Woven bone in which bone trabeculae oriented prependicular to the surface.

• Mild inflamed fibrous connective tissue is evident between trabeculae.

Bone disease

Cherubism

• Features: • Bilateral multilocular radioluency• Children 4-8 years• Differential diagnosis:• Aneurysmal bone cyst - hyperparathyrodism

Fibrous dysplasia of bone

• Features: • Chineese script writing• Orange peel – smoke screen – ground glass• Sexual precocity – café au lait pigmentation• Differential diagnosis:• Familial fibrous dysplasia

Paget

• Histopathology:• Bone trabeculae surrounded by osteoblasts.• Bone trabeculae surrounded by osteoclasts.• Mosaic appearance.• Features:• Deafness – blindness – lion like face• Elevated alkaline phosphatase• Hypercementosis• Differential diagnosis:• COC – focal sclerosing osteomyelitis – diffuse sclerosing

osteomyelitis

Hyperparathyroidism

• Histopathology:• Multinucleated giant cells• Features:• Brown tumor• Mutilocular• Normal serum alkaline phosphatase , increased

serum calcium, parathormone (PTH) • Differential diagnosis:• Cherubism – Anuerysmal bone cyst