Odontogenic Fibroma

Odontogenic fibroma is a benign mesenchymal odontogenic tumor typically characterized by a varying number of odontogenic epithelium in a mature fibrous matrix. It is divided into two types, namely, intraosseous /central odontogenic fibroma (COF) and extraosseous /peripheral odontogenic fibroma (POF) [1–6]. Histologically, COF has two main subtypes, namely simple COF (epithelial-poor) and complex COF (epithelial-rich) [7–10]. In the 2017 WHO classification, the panel excluded the subtype pf “epithelial-poor or simple” of odontogenic fibroma for poor definition [8–13]. COF typically includes granular cell odontogenic fibroma, odontogenic fibroma consisting of pleomorphic fibroblasts, and odontogenic fibroma exhibiting giant cell response [9, 14–17]. COF is a rare odontogenic tumor, which occurs mostly in females, with a male to female ratio of about 1:2.2. The age of onset is 4–80 years old (average 40 years old). It can occur in both maxilla and mandible, usually before the maxillary first molar and behind the mandibular first molar [9]. About 1/3 of COF may be associated with unerupted third molar. Peripheral odontogenic fibroma is more common than COF, with a wide age range of onset. It has been reported in literature that odontogenic fibroma may strike to people at the age between 11 and 90, with a peak at the age between 20 and 40 years. It is more common in females, and can occur in both maxilla and mandible, usually in mandibular buccal gums. The main treatment of odontogenic fibroma is surgical curettage or excision. Odontogenic fibroma has a prognosis with no tendency of recurrence.