AtlasFibro-osseousOssifying Fibroma

Fibro-osseous Lesions

Ossifying Fibroma

aka Cemento-ossifying Fibroma · COF

Benign well-demarcated encapsulated fibro-osseous neoplasm of tooth-bearing regions of the jaws; unlike fibrous dysplasia, it can be shelled out.

Border
Well defined
Rx
Enucleation
Variant risk
Juvenile aggressive

§ overviewOverview

Benign encapsulated fibro-osseous neoplasm composed of cellular fibrous tissue with variable bone/cementum-like mineralisation.

§ epidemiologyEpidemiology

Adults 20–40 y; F > M; mandibular premolar/molar region most common site.

§ clinicalClinical Features

  • 01Slow-growing painless jaw swelling with bucco-lingual expansion
  • 02Displacement of teeth
  • 03Well-defined lesion — key distinction from fibrous dysplasia

§ differentialDifferential Diagnosis

  • 01Fibrous dysplasia (poorly demarcated, ground-glass)
  • 02Cemento-osseous dysplasia (multifocal, no capsule)
  • 03Ameloblastoma

§ histopathHistopathology

  • 01Fibrous stroma with variable cellularity
  • 02Trabeculae of woven bone and basophilic cementum-like calcifications
  • 03True capsule (allows enucleation)

§ radiographicRadiographic Features

  • 01Well-defined unilocular radiolucent-to-mixed lesion with thin sclerotic border
  • 02Progressive centripetal mineralisation
  • 03Downward bowing of inferior mandibular border

§ investigationsInvestigations

  • 01OPG, CBCT to define margins
  • 02Incisional biopsy for diagnosis

§ classificationClassification

  • 01Conventional (cemento-)ossifying fibroma
  • 02Juvenile trabecular OF
  • 03Juvenile psammomatoid OF

§ treatmentTreatment

  • 01Complete surgical enucleation with curettage of the bony cavity — curative
  • 02Segmental resection for large or recurrent juvenile variants

§ complicationsComplications

  • 01Recurrence <10% for adult OF, higher for juvenile variants

§ prognosisPrognosis

Excellent for classical OF; juvenile variants more aggressive with higher recurrence.

§ examKey Examination Points

  • 01Well-circumscribed vs FD's diffuse border
  • 02Cortical bowing on CBCT

§ revisionQuick Revision Summary

  • 01Encapsulated · enucleation curative · JOF more aggressive

§ vivaBDS Viva Questions

  • 01Differentiate OF from fibrous dysplasia.
  • 02Juvenile variants?
  • 03Treatment approach?

§ mcqsMCQs — Assessment (3)

Question 1

Key feature separating OF from FD:

Question 2

Treatment of choice:

Question 3

Most aggressive variant:

References

  1. WHO Head & Neck Tumours 2022

Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.