Infective osteomyelitis

• Tuberculous osteomyelitis
• Syphilitic osteomyelitis
• Actinomycotic osteomyelitis

Tuberculous osteomyelitis

• Non healing sinus tract formation
• Age group affected is around 15 – 40 years.
• Commonly seen in phalanges and dorsal and lumbar vertebrae.
• Usually occurs secondary to tuberculosis of lungs.
• Cases have been reported where mandibular lesions were not associated with pulmonary disease.
• Another common entrance is through a carious tooth via open pulp.
• Usually affects long bones and rare in jaws.
• Results when blood borne bacilli lodge in cancellous bone. Usually in ramus , body of mandible. may mimic parotid swelling or submassetric abscess.

Syphilitic osteomyelitis

• Difficult to distinguish syphilitic osteomyelitis of the jaws from pyogenic osteomyelitis on clinical & radiographic examination.
• Main features are progressive course & failure to improve with usual treatment for pyogenic osteomyelitis.
• Massive sequestration may occur resulting in pathologic fracture.
• If unchecked, eventually causes perforation of the cortex.

Actinomycotic Osteomyelitis

• The organisms thrive in the oral cavity, especially tissues adjacent to mandible.
• May enter the bone through a fresh wound, carious tooth or a periodontal pocket at the gingival margin of erupting tooth.
• Soft or firm tissue masses on skin, which have purplish, dark red, oily areas with occasional zones of fluctuation.
• Spontaneous drainage of serous fluid containing granular material.
• Regional lymph nodes occasionally enlarged.
• Mimics parotitis / parotid tumors

• Inverted Pear-shaped Radiolucency: Globulomaxillary cyst.

  • Associated teeth need not be non-vital.

  • Klestadts’s cyst: Soft tissue variant of Globulomaxillary cyst.

• Tear Drop-shaped Radiolucency: Lateral Periodontal Cyst.

  • Associated teeth are vital.

• Cluster of Similar Cysts / Cluster of Grapes: Botryoid Odontogenic Cyst.

Miescher Cheilitis

• Definition: Granulomatous inflammation confined to the lip

Melkersson–Rosenthal Syndrome

Triad:

1. Facial palsy
2. Cheilitis granulomatosa
3. Fissured tongue

Ascher Syndrome

Triad:

1. Double lip
2. Blepharochalasis
3. Nontoxic thyroid enlargement

Double Lip

• Appearance: Cupid's bow

• 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

1. Zone 1 – Normal Dentin:
   Healthy tissue; no treatment needed

2. Zone 2 – Subtransparent Dentin:
   Acid-demineralized, no bacteria, remineralizable; preserve

3. Zone 3 – Transparent Dentin:
   Softened, no bacterial invasion; remineralizable; preserve

4. Zone 4 – Turbid Dentin:
   Bacterial invasion; not remineralizable; must be removed

5. Zone 5 – Infected Dentin:
   Fully decomposed; heavily infected; must be removed

• 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.