Central odontogenic fibroma (COF) is an extremely rare benign tumor, accounting for only about 0.1% of all odontogenic tumors occurring in the jawbone [1,2]. COF is a neoplasm composed of mature fibrous tissue, including odontogenic epithelium, and may contain calcified material [3]. Most lesions progress slowly within the jawbone and manifest as painless cortical bone expansion, with radiographic findings typically showing well-defined unilocular or multilocular radiolucent lesions. Clinically, many cases are asymptomatic and are often incidentally discovered, although some patients may present with pain and swelling due to tumor growth, tooth displacement, or evidence of root resorption [4]. In most cases, lesions are unilocular and exhibit features resembling a unicystic ameloblastoma or odontogenic cyst. Multilocular lesions of relatively larger size may exhibit features resembling an ameloblastic fibroma or odontogenic myxoma. In some instances, lesions may demonstrate indistinct borders and a mixed radiographic appearance of radiolucency and radiopacity [5,6].

Treatment of COF involves complete surgical excision, taking into account various factors such as the size and location of the tumor, the patient’s age, and general condition of patients, sometimes including reconstructive procedures following surgical removal. In most cases, clinicians may choose for relatively conservative excisional surgery, with no histologically clear evidence of encapsulation [5,7]. Due to the rarity of COF occurrence, there is a significant lack of discussion regarding the necessity of tooth extraction in conjunction with excisional surgery for COF treatment.

This case report presents cases of two female patients aged 58 and 56, diagnosed with COF at the Department of Oral and Maxillofacial Surgery, Chosun University Hospital in 2023. In contrast to the first case, the second case initially opted for preserving the affected tooth but eventually required extraction due to unfavorable outcomes. Reflecting on these two case reports prompts consideration of the prognosis of the affected tooth and the decision regarding extraction in treating COF.

The utilization of patient medical records and radiographic/clinical images in this case was conducted with approval (CUDHIRB 2401 002) from the Institutional Review Board of Chosun University Dental Hospital.

Case 1

The patient, a 58-year-old female, presented to the Department of Oral and Maxillofacial Surgery at Chosun University Dental Hospital in February 2023, reporting mobility and discomfort in the maxillary left first premolar that had begun a month prior. She was referred from a local clinic. The patient’s was diagnosed with diabetes and hyperlipidemia. Computed tomography showed radiolucent lesions with a unilocular appearance extending from the distal area of maxillary left first premolar to the mesial area of the maxillary left canine, as observed on radiographic images (Fig. 1, 2). Upon oral examination, mild mobility of tooth #24 was observed, with no signs of swelling or suppuration. Electric pulp testing was not performed on affected tooth.

Fig. 1. Pre-operative computed tomography views sections.

Fig. 2. Pre-operative panoramic view of lesion.

Under general anesthesia, extraction and curettage were performed on the maxillary left canine, first premolar, and second premolar (Fig. 3). Following this, bone grafting using allogenic bone was carried out. Palatal root resorption was observed in the extracted maxillary left first premolar. By Histopathological examination, the lesion was diagnosed with COF with an amyloid-rich variant. As of February 2024, there has been no evidence of recurrence.

Fig. 3. Extracted tooth after surgery (upper left canine, premolars).

Case 2

The patient, a 56-year-old female, visited our clinic in January 2023 for evaluation of a radiolucent lesion extending from the periapical area of the maxillary right first premolar to the buccal aspect of the right maxillary sinus, which was referred from a local clinic. Her medical history included hyperlipidemia and thyroidectomy. Radiographic findings of the affected area had been observed for two years without symptoms, but she presented with intermittent pain starting three weeks prior to the visit. Panoramic and computed tomography images showed a unilocular radiolucent lesion extending from the root surface of the maxillary right first molar to the buccal aspect of the maxillary sinus, with involvement of the adjacent cortical bone (Fig. 4). There were no signs of infection upon intraoral examination, but there was palpation and tenderness on the buccal aspect of the maxillary right first premolar. Electrical pulpal vitality test showed all positive signs from the maxillary right canine to the second premolar, with no evidence of mobility in any teeth.

Fig. 4. (A) Pre-operative (OP) panoramic view of lesion on first-visit of patient. Well-defined lesion is seen on upper right premolar area. (B) Post-OP panoramic view. Right upper canine was extracted and bone graft materials are packed on excisioned lesion area.

On the initial visit, under local anesthesia, an incisional biopsy was performed. Histopathological examination result was scattered odontogenic epithelium suspicious for COF along with fibromyxoid tissue. In March 2023, under general anesthesia, extraction and enucleation were performed on the maxillary right canine, followed by bone grafting using allograft and bone morphogenetic protein (Fig. 5). The decision was made to preserve teeth other than the maxillary right canine as their vitality and stability were maintained, and there was no mobility or signs of root resorption.

Fig. 5. (A) Post-operative 3 months after, patient came complains the swelling, and radiolucency was seen on radiographic examination and a pulp vitality of upper right lateral incisior and 1st premolar were negative. (B) After extratction of upper right lateral incisior and premolars and enucleation was done. Bone graft was done after curettage.

Three months post-surgery, the patient presented with swelling at the surgical site and clinical signs of inflammation. Upper right lateral incisior 1st premolar showed loss of vitality, negative responses to vitality and electric pulp testing and evidence of root resorption. Under local anesthesia, additional extraction and enucleation were performed on the maxillary right premolars and lateral incisior, followed by additional bone grafting using allograft. Histopathological examination did not found any tumor recurrence. As of February 2024, there have been no signs of recurrence and temporary removable partial denture was made.

Due to the rare incidence of COF, it is relatively less understood among clinicians, leading to challenges in establishing definitive treatment guidelines. Bennabi et al. [8] conducted a literature review on the etiology, epidemiology, histological classification, treatment, and prognosis of COF. Based on an analysis of 81 articles, they reported that COF tends to expand without invading adjacent structures in 40% of cases, with tooth displacement observed in 40% and external root resorption in 24.4%. Surgical intervention with tooth extraction was performed in 19.3% of cases, often due to the ease of access to the lesion or mobility caused by external root resorption [8].

Leite et al. [9] reported no recurrence following thorough enucleation and selective extraction, while Correa Pontes et al. [10] stated that complete excision is the best treatment for COF, as it is typically easily removable without adherence to surrounding bone, with no reports of malignant transformation.

In the two cases described, the affected teeth showed signs of vitality, and there were no symptoms such as mobility observed at intial examination. Consequently, instead of extracting all teeth involved in the lesion, only right upper canine was removed. However, shortly after the surgery, a loss of vitality in the affected teeth and signs of infection were detected. From the author’s perspective, it is necessary to consider extraction of teeth affected by the lesion based on surgical accessibility and anticipated prognosis. However, for adjacent vital tooth, conservative measures should be considered to maintain their function, although their prognosis may be compromised due to inadequate bone support and loss of vitality caused by the lesion. Clinicians need to carefully assess the extent of the lesion and its relationship with adjacent teeth to determine appropriate extraction.

As previously mentioned, due to the rarity of COF, there is a significant lack of clear treatment guidelines regarding tooth extraction, and clinicians often choose to selective extraction based on their clinical judgment [7]. This case report encourages clinicians to reflect on the necessity of making well-informed decisions regarding the preservation or extraction of affected teeth when making treatment decisions. It aims to assist in the development of future treatment strategies.

This study was supported by research fund from Chosun University Dental Hospital, 2023 (funding number: 2023-3).

The authors declare that they have no competing interests.