Prominent osteolysis in the maxilla: case report of an odontogenic fibroma mimicking a cyst

BMC Oral Health (2023) 23:297 Raabe et al. BMC Oral Health https://doi.org/10.1186/s12903-023-03008-9 Open Access CASE REPORT Prominent osteolysis in the maxilla: case report of an odontogenic fibroma mimicking a cyst Clemens Raabe1* , Matthias Dettmer2,3 , Daniel Baumhoer4   and Valerie G. A. Suter1    Abstract Background Odontogenic fibroma (OF) is a rare benign odontogenic tumor of ectomesenchymal origin, mostly affecting the tooth-bearing portions of the jaws in middle-aged patients. Whilst small lesions tend to be clinically asymptomatic, varying unspecific clinical symptoms occur with an increase in size and may mimic odontogenic or other maxillofacial bone tumors, cysts, or fibro-osseous lesions of the jaws. Case presentation A 31-year-old female patient presented with a hard, non-fluctuating protrusion in the vestibule of the upper right maxilla. It was visualized on cone beam computed tomography (CBCT) as space-occupying osteolysis with the displacement of the floor and facial wall of the maxillary sinus, mimicking a cyst-like lesion. The tissue was surgically removed and identified as an OF in the histopathological examination. One year after the surgery, restitution of regular sinus anatomy and physiological intraoral findings were observed. Conclusions This case report emphasizes that rare entities, like the maxillary OF presented, often demonstrate nonspecific clinical and radiological findings. Nevertheless, clinicians need to consider rare entities as possible differential diagnoses and plan the treatment accordingly. Histopathological examination is essential to conclude the diagnosis. OF rarely recur after proper enucleation. Keywords Odontogenic Tumors, Jaw Neoplasms, Osteolysis, Fibroma Background Odontogenic fibroma (OF) is a rare neoplasm of mature fibrous or fibromyxoid connective tissue occurring in the jawbones and accounting for < 1% of all odontogenic tumors [1–4]. The current WHO classification lists OF in the chapter on benign mesenchymal odontogenic tumors *Correspondence: Clemens Raabe 1 Department of Oral Surgery and Stomatology, School of Dental Medicine, ZMK Bern, University of Bern, Bern, Switzerland 2 Institute of Pathology, University of Bern, Bern, Switzerland 3 Institute of Pathology, Klinikum Stuttgart, Katharinenhospital, Stuttgart, Germany 4 Bone Tumor Reference Center at the Institute of Pathology, University Hospital Basel, University of Basel, Basel, Switzerland [4], including the even rarer amyloid, granular cell, ossifying, and hybrid subtypes that can show features of central giant cell granuloma [4]. According to the site of presentation, central and peripheral OF can be distinguished. The OF usually represents a locally aggressive lesion originating from ectomesenchymal elements of the tooth-forming structures with unknown etiology and molecular pathogenesis [4–8]. The reported mean age for the diagnosis of OF is 34 years, although all age groups (range 3 – 80 years) may be affected [6]. Slight predilections were found for females (2.2:1 males) and the maxilla (53%, mandible 47%) [4, 8]. In the mandible, OF is predominant in the molar region (58%), followed by the premolar region (39%), and the ramus (26%). In the maxilla, OF is usually located in the premolar region (63%), followed by the incisor © The Author(s) 2023. 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The Creative Commons Public Domain Dedication waiver (http://creativeco mmons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Raabe et al. BMC Oral Health (2023) 23:297 region (49%) and the molar region (19%) [6]. Lesion sizes of 3 – 130 mm (mean 28 mm) were reported in a recent systematic review of cases [7]. Usually, small lesions tend to be clinically asymptomatic and present as well-defined unilocular radiolucencies with corticated margins in the radiological examination [4, 7, 8]. With an increase in size, pain, expansion, or depression of the alveolar bone, and displacement or loosening of teeth are frequently observed symptoms [4, 7, 8]. More expansive lesions may present as multilocular radiolucencies with signs of cortical expansion in the radiological examination [4, 7, 8]. Furthermore, root resorption can occur [8]. More rarely, a mixed radiolucent-radiopaque appearance has also been described in the literature [8, 9]. As the clinical and radiologic features are non-specific and may mimic odontogenic or other maxillofacial bone tumors, cysts, or fibro-osseous lesions of the jaws, OF represents diagnostic challenges for the clinician. Histopathological examination is mandatory for proper diagnosis and demonstrates mature fibrous connective tissue with a proliferation of bland spindle cells. Varying amounts of inactive-looking odontogenic epithelium may be present or completely absent [9] Focal calcifications are commonly observed [4]. Generally, enucleation with preservation of surrounding structures is the treatment of choice for OF. Recurrences only rarely occur and are generally related to incomplete removal of the tumor [8, 9]. This case documents the rare occasion of an OF in the upper jawbone with expansion into the maxillary sinus, Page 2 of 6 presenting clinical and radiographic aspects that resemble those of odontogenic cysts or other osteolytic lesions. Case presentation A 31-year-old female patient felt a slowly growing swelling and mild pain in the right maxilla and consulted her private dentist, who performed a local incision and drainage. As symptoms persisted, the dentist referred the patient to the Department of Oral Surgery and Stomatology at the University of Bern. The patient was a smoker (10 cigarettes per day, cumulative dose of 10 pack years). Chronic bronchitis and penicillin intolerance were noticed in the medical history. The clinical head and neck examination showed a mild prominence of the right cheek and intact sensorimotor functions. No lymph nodes were palpable. Intraorally, a hard, non-fluctuating, and painless swelling in the vestibule of the right maxilla (FDI regions 15–17) was present (Fig. 1A). The dentition was unsuspicious, (...truncated)