Ossifying fibroma (OF) is a benign fibro-osseous lesion characterized by the proliferation of fibrous connective tissue containing immature bone and/or cementum-like hard tissue. Although the pathogenesis of OF remains unclear, trauma, previous extractions, and periodontitis are considered potential trigger factors. OF is more common in women aged from the second to fourth decades. Clinically, OF is characterized by slow-growing and asymptomatic swelling, often observed incidentally on radiological examinations. OF occurs more frequently in the mandible, particularly above the mandibular canal. Herein, we present a rare case of OF in an 18-year-old man initially misdiagnosed as a static bone cavity. The lesion was first observed as a radiolucent finding below the left mandibular canal on a panoramic radiograph. Later, cone-beam computed tomography (CBCT) imaging revealed the presence of calcifications within the lesion. Additionally, CBCT confirmed the presence of the lesion within the lingual cortical bone, revealing lingual swelling and thinning of the outer cortex. Enucleation was successfully performed under general anesthesia without any postoperative complications. Histopathological examination confirmed the diagnosis of OF, revealing mineralized tissue and proliferating fibrous connective tissue. This case underscores the challenges in diagnosing OF, particularly when it is located below the mandibular canal, emphasizing the importance of thorough imaging and differential diagnosis to avoid misinterpretation as a static bone cavity.

UNASSIGNED: Peripheral ossifying fibroma (POF) is a solitary gingival growth thought to arise from the gingiva, periosteum or the periodontal ligament. It is a slow-growing, benign, progressive lesion that is limited in size.
UNASSIGNED: This article describes a case of ossifying fibroma of a peripheral variant that occurred in a 26-year-old female in the anterior region of the lower jaw and presented as a growth on the gingiva. Since it was difficult to diagnose clinically, a pathological evaluation was mandatory. Upon pathological confirmation of the diagnosis, the lesion was surgically excised up to the periosteum. This was deemed to be the required treatment yet, since the recurrence rate is high for POF (8% to 20%), the patient must be followed up yearly to check for recurrence.
UNASSIGNED: Le fibrome ossifiant périphérique (FOP) est une excroissance gingivale solitaire dont on pense qu’elle provient des gencives, du périoste ou du ligament parodontal. Il s’agit d’une lésion progressive, bénigne et à croissance lente dont la taille est limitée.
UNASSIGNED: Cet article décrit le cas d’une variante périphérique du fibrome ossifiant survenue chez une femme de 26 ans, dans la région antérieure de sa mâchoire inférieure et se présentant comme une excroissance sur la gencive. Comme il était difficile d’établir un diagnostic clinique, une évaluation pathologique a été nécessaire. Après confirmation pathologique du diagnostic, la lésion a été excisée jusqu’au périoste lors d’une opération chirurgicale. On a jugé ce traitement nécessaire, puisque le taux de récidive du FOP est élevé (entre 8 % et 20 %). La patiente doit faire l’objet d’un suivi annuel pour rechercher toute récidive éventuelle.

The World Health Organization\'s (WHO) 2022 update on the classification of odontogenic and maxillofacial bone tumors has revolutionized diagnostic and treatment paradigms by integrating novel molecular insights. Fibro-osseous lesions of the maxillo-facial bones constitute a heterogeneous group encompassing fibrous dysplasia, Psammomatoid Ossifying Fibroma (PSOF), Juvenile Trabecular Ossifying Fibroma (JTOF), and other variants. Despite histological similarities, their distinct clinical manifestations and prognostic implications mandate precise differentiation. The intricacies of diagnosing fibro-osseous lesions pose challenges for pathologists, maxillofacial surgeons, dentists and oral surgeons, underscoring the importance of a systematic approach to ensure optimal patient management. Herein, we present two cases, fibrous dysplasia and Cemento-Ossifying Fibroma, detailing their clinical encounters and management strategies. Both patients provided informed consent for publishing their data and images, adhering to ethical guidelines.

OBJECTIVE: In this study, our aim was to develop and validate the effectiveness of diverse radiomic models for distinguishing between gnathic fibrous dysplasia (FD) and ossifying fibroma (OF) before surgery.
METHODS: We enrolled 220 patients with confirmed FD or OF. We extracted radiomic features from nonenhanced CT images. Following dimensionality reduction and feature selection, we constructed radiomic models using logistic regression, support vector machine, random forest, light gradient boosting machine, and eXtreme gradient boosting. We then identified the best radiomic model using receiver operating characteristic (ROC) curve analysis. After combining radiomics features with clinical features, we developed a comprehensive model. ROC curve and decision curve analysis (DCA) demonstrated the models\' robustness and clinical value.
RESULTS: We extracted 1834 radiomic features from CT images, reduced them to eight valuable features, and achieved high predictive efficiency, with area under curves (AUC) exceeding 0.95 for all the models. Ultimately, our combined model, which integrates radiomic and clinical data, displayed superior discriminatory ability (AUC: training cohort 0.970; test cohort 0.967). DCA highlighted its optimal clinical efficacy.
CONCLUSIONS: Our combined model effectively differentiates between FD and OF, offering a noninvasive and efficient approach to clinical decision-making.

Craniofacial fibro-osseous lesions represent a diverse spectrum of pathologic conditions where fibrous tissue replaces healthy bone, resulting in the formation of irregular, woven bone. They are more commonly diagnosed in young people, with treatment strategies dependent on clinical behavior and skeletal maturity. This article discusses the examples of craniofacial fibro-osseous lesions, based on the latest classifications, along with their diagnostic criteria and management.

This review directs the focus on the imaging features of various fibro-osseous lesions and other bone lesions that can be of similar presentation. Broad diagnosis of \"fibrous osseous lesion\" may culminate in improper treatment and management. Radiographic discriminating factors between these entities are highlighted and summarized to improve the diagnostic process when encountering these lesions.

UNASSIGNED: Preoperative imaging for some unusual lesions in the sellar region can pose challenges in establishing a definitive diagnosis, impacting treatment strategies.
UNASSIGNED: This study is a retrospective analysis of eight cases involving unusual sellar region lesions, all treated with endoscopic endonasal transsphenoidal surgery (EETS). We present the clinical, endocrine, and radiological characteristics, along with the outcomes of these cases.
UNASSIGNED: Among the eight cases, the lesions were identified as follows: Solitary fibrous tumor (SFT) in one case, Lymphocytic hypophysitis (LYH) in one case, Cavernous sinus hemangiomas (CSH) in one case, Ossifying fibroma (OF) in two cases; Sphenoid sinus mucocele (SSM) in one case, Pituitary abscess (PA) in two cases. All patients underwent successful EETS, and their diagnoses were confirmed through pathological examination. Postoperatively, all patients had uneventful recoveries without occurrences of diabetes insipidus or visual impairment.
UNASSIGNED: Our study retrospectively analyzed eight unusual lesions of the sellar region. Some lesions exhibit specific imaging characteristics and clinical details that can aid in preoperative diagnosis and inform treatment strategies for these unusual sellar diseases.

Juvenile psammomatoid ossifying fibroma (JPOF) is an osteofibrous neoplasm that originates in the craniofacial skeleton typically during the first three decades of life. JPOFs usually involve the orbit, paranasal sinuses or the jaws. Extensive involvement of the anterior cranial base with compromised visual function is a rare phenomenon. In such clinical context, a definite diagnosis can only be made on the basis of histopathological findings, given the absence of pathognomonic radiological features. Despite being considered a benign entity, JPOFs present a locally aggressive behavior. Therefore, these neoplasms must be included in the differential diagnosis in every patient harboring a skull base osteofibrous lesion, and, once diagnosed, gross total surgical removal should be attempted. In this study, we present our experience in the diagnosis and treatment of a patient diagnosed with a giant JPOF involving the cranial base.

Cemento-ossifying fibroma (COF) of the jaws is currently classified as a benign mesenchymal odontogenic tumor, and only targeted approaches have been used to assess its genetic alterations. A minimal proportion of COFs harbor CDC73 somatic mutations, and copy number alterations (CNAs) involving chromosomes 7 and 12 have recently been reported in a small proportion of cases. However, the genetic background of COFs remains obscure. We used a combination of whole-exome sequencing and RNA sequencing to assess somatic mutations, fusion transcripts, and CNAs in a cohort of 12 freshly collected COFs. No recurrent fusions have been identified among the 5 cases successfully analyzed by RNA sequencing, with in-frame fusions being detected in 2 cases (MARS1::GOLT1B and PARG::BMS1 in one case and NCLN::FZR1 and NFIC::SAMD1 in the other case) and no candidate fusions identified for the remaining 3 cases. No recurrent pathogenic mutations were detected in the 11 cases that had undergone whole-exome sequencing. A KRAS p.L19F missense variant was detected in one case, and 2 CDC73 deletions were detected in another case. The other variants were of uncertain significance and included variants in PC, ACTB, DOK6, HACE1, and COL1A2 and previously unreported variants in PTPN14, ATP5F1C, APOBEC1, HDAC5, ATF7IP, PARP2, and ACTR3B. The affected genes do not clearly converge on any signaling pathway. CNAs were detected in 5/11 cases (45%), with copy gains involving chromosome 12 occurring in 3/11 cases (27%). In conclusion, no recurrent fusions or pathogenic variants have been detected in the present COF cohort, with copy gains involving chromosome 12 occurring in 27% of cases.

OBJECTIVE: The purpose of this study is to evaluate the association between hyperparathyroidism (PHPT), parathyroid hormone levels, and calcium levels in patients diagnosed with benign fibro-osseous lesions such as fibrous dysplasia (FD), ossifying fibroma (OF), central giant cell granulomas (GCG).
METHODS: This is a retrospective, single-center study from a sample of patients who underwent surgical treatment of FD, OF, and GCG at Mayo Clinic between 1996 and 2021. Patient demographics, history of PHPT, histopathological diagnosis, and relevant laboratory values such as parathyroid hormone (PTH), serum calcium, vitamin D, and alkaline phosphatase were collected.
RESULTS: Of the patients diagnosed with FD (n = 64), OF (n = 24), and GCG (n = 5), a diagnosis of PHPT was found in 2 patients (3.1%), 1 patient (4.2%), and 0 patients (0%), respectively. Elevated PTH levels (>65 pg/mL) were observed in 3 patients (4.7%) with FD, 1 patient (4.2%) with OF, and 1 patient (20%) with GCG. Mean (standard deviation) calcium levels were 9.3 (0.6) mg/dL in the FD group, 9.4 (0.5) mg/dL in the OF group, and 9.3 (0.6) mg/dL in the GCG group. Patients with fibro-osseous jaw tumors including FD, OF, and GCG may have increased risk of PHPT compared to the general population.
CONCLUSIONS: Patients with benign jaw tumors including FD, OF, and GCG may have increased risk of PHPT compared to the general population. Surgeons treating these benign tumors need to be cognizant of these findings, obtain appropriate laboratory studies, and incorporate multidisciplinary care including endocrinologists, endocrine surgeons, and maxillofacial surgeons.