Mandible & maxilla
Benign odontogenic tumors
Odontogenic fibroma
Last author update: 1 February 2018
Last staff update: 11 August 2022
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PubMed Search: Odontogenic fibroma maxilla
Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Sites | Clinical features | Diagnosis | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Clinical images | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Martinez, A. Odontogenic fibroma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxillaodontogenicfibroma.html. Accessed January 17th, 2025.
Definition / general
- Rare, benign mesenchymal odontogenic tumor composed of mature fibrous tissue with variable amounts of inactive appearing odontogenic epithelium
- Calcification may be present
- Two common variants:
- Intraosseous or central odontogenic fibroma
- Extraosseous or peripheral odontogenic fibroma, centered in gingival tissues associated with tooth bearing regions of jaws
- Rare variants (see Microscopic (histologic) description)
Essential features
- Strands or nests of odontogenic epithelium, with or without calcification, set in a variably cellular fibrocollagenous stroma
Terminology
- Odontogenic fibroma
- Central odontogenic fibroma
- Peripheral odontogenic fibroma
Epidemiology
- Peak age is 20 - 40 years
- Peripheral odontogenic fibroma is more common than central odontogenic fibroma
- Peripheral odontogenic fibroma: occurs 2x as often in females (El-Naggar: WHO Classification of Head and Neck Tumours, 4th Edition, 2017)
- Odontogenic fibroma: slight female predilection
Sites
- Mandible and maxilla affected equally
- Peripheral odontogenic fibroma
- More common along anterior gingival region
- Central odontogenic fibroma
- Most involving mandible are posterior to first molar
- Most involving maxilla are anterior to first molar
Clinical features
- Can be asymptomatic
- If symptomatic, can present with swelling and pain
Diagnosis
- Diagnosis dependent on clinical, radiologic and pathologic correlation
Radiology description
- Can present as a unilocular or multilocular radiolucency with distinct borders
- Root resorption and displacement of teeth have been reported
- ~10% exhibit radiopaque flakes that correlate with calcification
Radiology images
Images hosted on other servers:
IOPA showing irregular radiopaque masses
Multilocular radiolucency near 21, 22, 63, 24 and 25
Prognostic factors
- Peripheral odontogenic fibromas
- High recurrence rate, up to 50% (El-Naggar: WHO Classification of Head and Neck Tumours, 4th Edition, 2017)
- Central odontogenic fibromas
- Recurrence uncommon
Case reports
- 12 year old boy with a slow growing, asymptomatic gingival mass distal to the mandibular right first molar (Ann Med Surg (Lond) 2015;5:14)
- 14 year old boy with an asymptomatic firm and sessile gingival mass (Int J Clin Pediatr Dent 2017;10:103)
- 14 year old boy with concurrent central odontogenic fibroma and dentigerous cyst in the maxilla (J Oral Maxillofac Pathol 2017;21:149)
- 18 year old man with odontogenic fibroma of the posterior maxilla (Iran J Pathol 2016;11:435)
Treatment
- Peripheral odontogenic fibromas are usually treated by excision
- Central odontogenic fibromas are usually treated by enucleation and curettage
Clinical images
Images hosted on other servers:
Gingival masses
Gross images
Images hosted on other servers:
Surgical intervention of odontogenic fibroma
Microscopic (histologic) description
- Calcification can be seen in association with odontogenic epithelium and when extensive could consider classification as ossifying variant of odontogenic fibroma
- Ossifying variant of odontogenic fibroma: epithelial odontogenic islands intimately admixed with bone trabeculae (see Fig. 8 below)
- Granular cell odontogenic fibroma: variant characterized by granular cell appearance within the odontogenic epithelium or stromal granular cells
- Central odontogenic fibroma (COF) with amyloid-like protein deposition
- Characteristic COF with ovoid or globular acellular hyalinized structures and possible areas of periepithelial amyloid deposition (cuffing)
- Deposits positive for Congo red and demonstrated green birefringence under polarized light examination
- A positive immunohistochemical reaction pattern employing antibodies to odontogenic ameloblast associated protein (ODAM) confirmed that this protein is, in fact, odontogenic amyloid, as found in developing tooth germs (see Fig. 9 below)
- Central odontogenic fibroma associated with central giant cell granuloma (CGCG)
- In some cases, the COF and CGCG histologic components were not intimately admixed; rather, they were arranged in a juxtaposed yet separate dimorphic pattern
- In other cases, the two patterns comingle (see Fig. 7 below, Head Neck Pathol 2017 Aug 7 [Epub ahead of print])
Microscopic (histologic) images
Contributed by Kelly Magliocca, D.D.S., M.P.H.
Odontogenic fibroma
Case 1: Odontogenic fibroma with extensive calcification
Case 2: Odontogenic fibroma with giant cell reaction / giant cell granuloma
Case 3: Odontogenic fibroma
Images hosted on other servers:
Odontogenic fibroma of the maxilla
COF and dentigerous cyst in the maxilla
Islands of odontogenic epithelium within a cellular fibrous stroma
Features of peripheral odontogenic fibroma
Fig. 7 Odontogenic fibroma with central giant cell lesion
Fig. 8 Ossifying variant of COF
Fig. 9 Amyloid variant of COF
Differential diagnosis
-
Central odontogenic fibroma
- Ameloblastic fibroma
- Composed of odontogenic epithelial component strands, cords and islands that may exhibit peripheral palisading, reverse polarization and stellate reticulum
- Primitive appearing stroma that is delicate and lobular in appearance
- Desmoplastic fibroma
- Composed of fascicles of variably SMA positive myofibroblasts
- Consider desmoid tumor of bone
- Hyperplastic dental follicles with odontogenic fibroma-like islands
- Clinicoradiographically enlarged follicle surrounding impacted tooth
- Collections of odontogenic islands, lack dispersed nature of odontogenic fibroma (Oral Surg Oral Med Oral Pathol 1988;66:78)
- Odontogenic myxoma
- Spindled to stellate cells with eosinophilic cytoplasm set in myxoid matrix
- Binucleated "heart shaped" cells, mitoses and minimal atypia can be seen
- If abundant collagen is present, the term myxofibroma or fibromyxoma has been used
- Occasional scattered epithelial rests can be seen
- Sclerosing odontogenic carcinoma
- Rare, primary intraosseous carcinoma of the jaws with bland cytology, markedly sclerotic stroma and aggressive pattern of infiltration
- Single file thin cords, nests and strands of epithelium in a densely sclerotic stroma
- Epithelium or stroma may dominate in different areas
- Epithelium may be so compressed so as to be best seen with immunohistochemistry (such as cytokeratin AE1 / 3)
- Cytologically, individual epithelial cells are bland with uncommon mitoses
- Cytoplasm may show vacuolation or partial clearing
- Despite the bland cytological appearance, there is invasion of skeletal muscle and commonly, perineural invasion
Peripheral odontogenic fibroma
- Irritation fibroma
- Nodular lesion with a dermal proliferation of haphazard collagen bundles in response to local irritation
- Peripheral giant cell granuloma
- Proliferation of multinucleated giant cells, plump oval mononuclear cells and hemorrhage
- Has similar appearance to solid aneurysmal bone cyst but without USP6 rearrangements
- Pyogenic granuloma (lobular capillary hemangioma)
- Lobular proliferation of well formed, small capillary vascular channels with larger, feeder vessels
- Can show ulceration
Board review style question #1
- A mandibular mass that is radiolucent by plain radiograph, is characterized by strands or nests of inactive appearing odontogenic epithelium, with or without calcification, set in a variably cellular fibrocollagenous stroma.
- Central odontogenic fibroma
- Desmoplastic fibroma
- Odontogenic myxoma
- None of the above
Which of following is the best diagnosis?
Board review style answer #1
