Fibrous Dysplasia Of The Orbital Region

Fibrous Dysplasia Of The Orbital Region

Question. Classify firo­osseous lesions of oral cavity. Discuss clinical features, radiographic differential diagnosis, and management of fibrous dysplasia.
Or
Classify firo­osseous lesions of jaw. Discuss the clinical and histopathological features of fibrous dysplasia.
Or
Classify firo­osseous lesions of jaws. Describe in detail fibrous dysplasia.
Or
Classify firo­osseous lesions. Discuss in detail about the etiology, clinical, radiographic, and histopathologic features of fibrous dysplasia.
Or
Enumerate firo­osseous lesions of jaws and describe fibrous dysplasia in detail.
Or
Enumerate firo­osseous lesions. Describe in detail the clinical radiological and histopathological features of firous dysplasia.
Or
Classify firo­osseous lesions affcting the jaws.Write in detail about the etiopathogenesis, clinical features,radiographic features of firous dysplasia.
Or
Enumerate the firo­osseous lesions involving orofacial region. Describe firous dysplasia in detail with diagram.
Or
Classify firo­osseous lesions. Write in detail about firous dysplasia.

Answer.

Fibrous dysplasia is a skeletal developmental anomaly of the bone forming mesenchyme which manifests as a defect osteoblastic differentiation and maturation.

“Understanding the role of fibrous dysplasia in orbital bone pathology: Q&A explained”

Etiology/Etiopathogenesis

• Genetic: Fibrous dysplasia is caused by postzygotic mutation in GNAS1 gene which encodes a G­protein which stimulates production of cAMP. Mutation leads to excessive secretion of cAMP which leads to hyperfunction of endocrine organs, increase proliferation of melanocytes, and affect differentiation of osteoblasts. If mutation occur in early pre-embryonic life polystotic fibrous dysplasia
  occur. If mutation occur in early postembryonic life monostotic firous dysplasia occur.
• Developmental: As the disease begins in early life, it was considered to be developmental.
• Endocrine: Some of the investigators thought that it occurs due to local endocrinal disorders.

“Importance of studying fibrous dysplasia of the orbital region for better outcomes: Questions explained”

Clinical Features

• Monostotic Fibrous Dysplasia
  • It involves only one bone and pigmented skin lesions are present.
  • The sites which affcted are maxilla, mandible, ribs and femur.
  • It occurs in children younger than 10 years and both the sexes are equally affcted.
  • Maxilla is more commonly affected than the mandible and most of the changes occur in posterior region. The most common area involved is premolar area.
  • There is presence of unilateral facial swelling which is slow growing with intact overlying mucosa.
  • Swelling is painless but patient may feel discomfort.
  • There is presence of enlarging deformities of alveolar process mainly buccal and labial cortical plates.
  • In mandible, there is protrusion of inferior border of mandible.
  • The teeth present in the affcted area are malaligned and tipped or displaced.
  • Supernumerary teeth are often impacted and affcted the eruption of teeth.

“Common challenges in diagnosing fibrous dysplasia of the orbital region effectively: FAQs provided”

• Polyostotic Fibrous Dysplasia
  • It is seen during first and second decades of life.
  • Female predilection is seen with male to female ratio of 1:3.
  • Most common sites to be involved are skull, facial bones, clavicle, thighs, shoulder, chest and neck.
  • Café­au­lait spots are seen over the skin which are irregular in shape and are light brown melanotic spots.
  • Patient complains of recurrent bone pain.
  • There is expansion of jaws and asymmetry of facial bones which leads to enlargement and deformity.
  • Teeth eruption is not proper.

“Factors influencing success with orbital fibrous dysplasia treatment: Q&A”

Radiographic Features

Lesions Representing Dominance of Fibrous Tissue Or Osteolytic Stage of Fibrous Dysplasia

• Such lesions are generally radiolucent with ill defined borders. Defect in bone is unilocular but at times bony septa presents a picture of multilocular activity.
• Margins of lesion are well defied.
• Loss of lamina dura is evident.
• Resorption of roots is evident.

Lesions presenting mixed radiolucent and radiopaque picture Or Mixed stage of firous dysplasia

• The lesion got both the firous and osseous tissue so, i.e.
  the lesion presents both mixed radiopaque and radiolucent picture.
• Newly formed bone represents multiple small opacities of poor density. As they increases in size they appear granular.

“Steps to explain causes of orbital fibrous dysplasia: Genetic mutations vs GNAS gene involvement: Q&A guide”

Mature Lesions with Radiopacity or Mature Stage of Fibrous
Dysplasia

• In this stage, bone is prominent, i.e. they are referred to as mature lesions with radiopacity.
• Radiograph reveals orange peel appearance.
• In the affected area; teeth are bodily displaced and tilted.
• Bony expansion is seen on both distal and buccal aspects.
• As mandible get involved, vertical depth of bone is increased. Inferior border of mandible appears ribbon-like cortex. In various cases, area over cortex is lost, there is a curved downward projection of inferior margins of mandible. This appearance is called as thumbprint appearance.
• It also shows ground-glass appearance.

Radiographic Differential Diagnosis

Osteolytic Stage of Fibrous Dysplasia

• Central Giant cell granuloma: Trabeculae in central giant cell granuloma are faint while in firous dysplasia internal calcifiations are seen which are stippled and granular.
• Traumatic bone cyst: Cortical bulging, as well as displacement of teeth, is present in traumatic bone cyst while it is absent in firous dysplasia.

“Early warning signs of issues addressed by understanding orbital fibrous dysplasia pathogenesis: Common questions”

Mixed Stage of Fibrous Dysplasia

• Osteosarcoma: It presents its typical features as sunburst pattern and Codman’s triangle while fibrous dysplasia show granular appearance.
• Lymphoma of bone: Lymphoma of bone appears irregular as well as bizarre in radiographs while firous dysplasia is smooth and has well contoured boney margins.
• Cemento ossifying fibroma: Shape of cemento ossifying fibroma is rounded while of fibrous dysplasia is rectangular.
• Margins in cemento ossifying firoma are sharply defied while in firous dysplasia they are indistinct.

Mature Stage of Fibrous Dysplasia

• Paget’s disease: Ground glass appearance is present in both Paget’s disease and firous dysplasia. But in Paget’s disease complete effct is rarefaction.

“Role of abnormal bone remodeling in orbital fibrous dysplasia: Questions answered”

Management

• Surgical removal of the lesion should be done.
• Osseous contouring is done to correct the deformities so that esthetics of patient should be improved.