Painless unilateral maxillary swelling in an adolescent
14-year-old female
§Chief complaint
Gradual enlargement of the left cheek over 3 years
§Medical & dental history
- 01No cafe-au-lait macules, no endocrine abnormality
- 02Menarche normal
- 03No trauma or infection at the site
§Clinical examination
- 01Diffuse, bony hard, non-tender enlargement of the left maxilla with facial asymmetry
- 02Buccal expansion obliterating the sulcus; teeth displaced but vital
- 03Overlying mucosa normal; no paraesthesia
- 04No proptosis or visual disturbance
§ figuresFigures (5)
Fig. 1Medium power shot with the classic 'Chinese character' bone spicules.
“Bone FibrousDysplasia LP CTR” · Sarahkayb · CC BY-SA 4.0 · Wikimedia Commons
Fig. 2Immature bony trabeculae in a fibrous stroma.
“Bone FibrousDysplasia Jaw MP3 PA” · Sarahkayb · CC BY-SA 4.0 · Wikimedia Commons
Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Fibrous Dysplasia figures pending faculty review.
§Differential diagnosis
§Final diagnosis
Monostotic fibrous dysplasia of the left maxilla
The imaging signature is a ground-glass matrix with margins that blend imperceptibly into normal bone — the opposite of the sharply demarcated ossifying fibroma. Absence of cafe-au-lait macules and endocrinopathy excludes McCune-Albright syndrome.
§Investigations
- 01CT — ground-glass matrix, expansion, cortical thinning, indistinct borders
- 02Serum alkaline phosphatase mildly raised; calcium and phosphate normal
- 03Incisional biopsy where the diagnosis is not radiologically certain
- 04Endocrine screen and skeletal survey to exclude polyostotic disease
§Treatment plan
- 01Observation until skeletal maturity where function and appearance permit
- 02Conservative surgical recontouring for aesthetic or functional problems
- 03Avoid radiotherapy — risk of sarcomatous transformation
- 04Long-term clinical and radiographic review
§Surgical procedure
- 01Recontouring osteoplasty via an intraoral vestibular approach after growth stabilised
§Histopathology report
Irregular, curvilinear trabeculae of woven bone (Chinese-letter pattern) without osteoblastic rimming, lying in a cellular fibrous stroma that merges with surrounding bone. Fibrous dysplasia.
§Follow-up & outcome
- 01Facial symmetry improved after recontouring
- 02Stable at 3 years with no regrowth
- 03Advised on the small risk of malignant change
§Clinical pearls / learning points
- 01Fibrous dysplasia tends to stabilise after skeletal maturity — timing surgery matters.
- 02Never irradiate fibrous dysplasia.
- 03The absence of osteoblastic rimming histologically helps separate it from ossifying fibroma.
§References
- WHO Classification of Head and Neck Tumours, 5th ed. (2022).
§Similar cases
41 cases in the library