Central Cemento-Ossifying Fibroma: Primary Odontogenic or Osseous Neoplasm?

Benign fibro-osseous lesions: A retrospective study of sixty-four cases from a single institute, Riyadh, Saudi Arabia

Objective

Benign fibroosseous lesions (BFOLs) encompass a heterogenous collection of bone conditions characterized by replacing normal bone with fibro-collagenous tissue with osteoid or woven bone, and cementicles. Despite their clinical significance, the frequency of BFOLs in Saudi Arabia still needs to be assessed.

Methods

This retrospective study investigated the frequency and demographics of BFOLs in Riyadh, Saudi Arabia, by retrieving all cases recorded between January 1984 and January 2013 from a single Oral Pathology Laboratory archive.

Results

A total of 64 cases were classified as BFOLs, with a predominance in females (67.2 %) and a median age of 21.5 years. The most prevalent condition identified was fibrous dysplasia (45.31 %), followed by cemento-ossifying fibroma (26.56 %). There were significant sex differences between BFOLs, with a p-value of 0.03. FD was predominantly located in the maxilla (65.5 %), whereas COF was predominantly found in the mandible (82.3 %). Recurrence was observed in 17.2 % of patients with FD, in contrast to no reported recurrence in patients with COF.

Conclusion

This study represents the first exploration of BFOL frequency and demographics in Riyadh, Saudi Arabia, highlighting the need for further investigations to comprehensively understand the nature of these lesions in our population.

Differential diagnosis of cemento-osseous dysplasia and periapical cyst using texture analysis of CBCT

BACKGROUND

Radiolucencies found at the root apex in patients with cemento-osseous dysplasia (COD) may be mistaken for periapical cysts (PC) of endodontic origin. The purpose of this study was to examine the utility of quantitative texture analysis using cone-beam computed tomography (CBCT) to differentiate between COD and PC.

METHODS

Patients who underwent CBCT at Wonkwang University Daejeon Dental Hospital between January 2019 and December 2022 and were diagnosed with COD and PC by clinical, radiologic, and, if necessary, histopathologic examination were included. Twenty-five patients each were retrospectively enrolled in the COD and PC group. All lesions observed on axial CBCT images were manually segmented using the open-access software MaZda version 4.6 to establish the regions of interest, which were then subjected to texture analysis. Among the 279 texture features obtained, 10 texture features with the highest Fisher coefficients were selected. Statistical analysis was performed using the Mann-Whitney U-test, Welch's t-test, or Student's t-test. Texture features that showed significant differences were subjected to receiver operating characteristics (ROC) curve analysis to evaluate the differential diagnostic ability of COD and PC.

RESULTS

The COD group consisted of 22 men and 3 women, while the PC group consisted of 14 men and 11 women, showing a significant difference between the two groups in terms of sex (p=0.003). The 10 selected texture features belonged to the gray level co-occurrence matrix and included the sum of average, sum of entropy, entropy, and difference of entropy. All 10 selected texture features showed statistically significant differences (p<0.05) when comparing patients with COD (n=25) versus those with PC (n=25), osteolytic-stage COD (n=11) versus PC (n=25), and osteolytic-stage COD (n=11) versus cementoblastic-stage COD (n=14). ROC curve analysis to determine the ability to differentiate between COD and PC showed a high area under the curve ranging from 0.96 to 0.98.

CONCLUSION

Texture analysis of CBCT images has shown good diagnostic value in the differential diagnosis of COD and PC, which can help prevent unnecessary endodontic treatment, invasive biopsy, or surgical intervention associated with increased risk of infection.

Thoughts on the Etiology of Cherubism

Cherubism is nowadays classified as an autoimmune disease and was first described in 1933. Although suspected at that time to be the result of defective tooth development, it was primarily classified as a bone disease caused by a mutation in the SH3BP2 gene. Despite a knock-in mouse model, phenotypic signs in the jaw area were not reproducible in this model. The features of classical cherubism can be attributed to a disturbed formation of the dental placode of the second molar. Since 2019, it has become clear that inhibition of the WNT pathway leads to the accumulation of SH3BP2 via tankyrase inhibition. As the dental placode is triggered via WNT (in epithelia) and MSX1 (in mesenchyme), aplasia of the second and third molars occurs due to a block in the WNT pathway. The mesenchymal part, which occurs prior to the body plan regulation of the WNT/MSX1 pathway, remains unaffected and provides the substrate for the giant cell granuloma. Considering macrophage polarization and the role of the extracellular matrix in general, cherubism is situated in the field of tension between autoimmune diseases and cancer. In this sense, we see the cause of cherubism in a WNT-related dysregulation, which can be proven postnatally in the neural crest-related tooth development of the replacement tooth ridge, both genotypically and phenotypically.

Periapical Cemento-Osseous Dysplasia: A Journey from Diagnostic Dilemma to Accurate Diagnosis with Use of 3D Imaging

Cemento-osseous dysplasia is a subgroup of fibro-osseous dysplasia commonly invading the tooth-bearing regions of the mandible quite often. These bony pathologies are asymptomatic and are seen on radiographs as an incidental finding. Accurate diagnosis of periapical cemento-osseous dysplasia is very crucial as it will help in the proper management of the patient as the incorrect diagnosis can lead to the unnecessary endodontic treatment of the concerned teeth as it may be misdiagnosed as a periapical pathology. We describe a case of periapical cemento-osseous dysplasia in which a 52-year-old woman had been experiencing discomfort in the right mental area of her mandible for the previous 6 months and had finally sought help at the outpatient department. This case study aims to highlight the significance of making an accurate diagnosis of cemento-osseous dysplasias in the tooth-bearing area.

Small biopsies in the head and neck: Bone and soft tissue

Bone and soft tissue lesions in the head and neck encompass not only a broad morphologic spectrum but also significant inherent clinicopathologic overlap. Epidemiology, radiology, and location - similar to the diagnostic assessment in other sites - are especially important considerations in the context of an established mesenchymal proliferation. Herein, the approach towards diagnosis is stratified by morphology (spindle, sarcomatoid, epithelioid, round cell), cellular lineage (fibroblastic, nerve sheath, rhabdomyogenic), and tumor grade (benign, low- to high-grade malignant) as the basis of further immunohistochemical or molecular investigation.

Large cemento-ossifying fibroma of the mandible involving the infratemporal and parapharyngeal spaces

Cemento-ossifying fibroma is a benign fibro-osseous lesion of the jaws. Cemento-ossifying fibroma develops from the periodontal ligament and contains multipotent stem cells that can form cementum, lamellar bone, and/or fibrous tissue. These tumours occur in the third and fourth decades of life with higher predilection of occurrence in the female population and seldom attain a large size. We report a rare case of cemento-ossifying fibroma in a 45-year-old man involving the body of the mandible and extending into the para-pharyngeal and infratemporal region. This article describes the clinical, radiographic, and histological features of a large cemento-ossifying fibroma of the mandible.

Clinical assessment of cemento-osseous dysplasia based on three-dimensional diagnostic imaging: A case report

Cemento-osseous dysplasia (COD) is a lesion in which periapical bone is replaced by fibrous tissue, including osseous or cementum-like tissue. In the initial stage of COD, radiolucencies are noted at the root apex on periapical radiography, which can be confused with apical periodontitis. Understanding of correct pathological condition and careful assessment of COD is critical to avoid unnecessary endodontic interventions in healthy teeth. This report describes the ability and usefulness of cone-beam computed tomography (CBCT) and multi-slice computed tomography (MSCT) to detect COD. The findings in this case suggest that MSCT is more appropriate than CBCT, especially for patients with early- to middle-stage COD. However, the radiation dose is higher in MSCT than in CBCT; the application of MSCT should be limited to assessment of whether treatment or surgical management is necessary.

Differential Diagnosis of Periapical Radiopacities and Radiolucencies

Periapical pathoses represent changes noted at the apices of teeth within the alveolar process that are suspected on examination, visualized via imaging, and confirmed via histopathology. They can be bone forming or destructive. There are pathologic entities that show both types of changes at the apical regions. These lesions must be identified if they are odontogenic in origin because treatment modalities differ. This article discusses identification of radiopaque and radiolucent lesions noted on radiographs. The common opacities and lucencies are described. When required, advanced imaging is used to depict changes within the bone near the periapical regions of mandibular and maxillary teeth.

[Differential diagnosis of cemento-osseous dysplasia of the maxilla. A case report]

Cemento-osseous dysplasia is a benign lesion which affects the jaw bones. It is a frequent incidental finding but no aggressive therapy is necessary. However, it may be confused with more aggressive entities, such as ossifying and cementifying fibroma, which do require treatment. There are no clear-cut histopathological criteria to differentiate between these entities. We present a case of a 13-year old boy who underwent a biopsy of a clinically undiagnosed maxillary lesion. Histopathological analysis revealed moderately cellular fibrous tissue with bone trabeculae with no osteoblastic rimming and clusters of intensely basophilic material corresponding to cementum. The final diagnosis was cemento-osseus dysplasia. The main histopathological features important in the distinction of these entities are discussed.

Central Osteoma of Maxilla Associated with an Impacted Tooth: Report of a Rare Case with Literature Review

Osteomas are benign osteogenic neoplasms caused by proliferation of mature compact or cancellous bone. Clinically they may be classified as peripheral, central or extraskeletal. Osteomas usually involve the craniofacial region with mandible being the most common site. Central osteoma of the jaws is a very rare entity with only 13 cases reported in the literature till date of which only five cases occurred in the maxilla. Here we present a case of a large central osteoma of anterior maxilla associated with an impacted tooth, the first of its kind and a review of literature.

Deletion of Menin in craniofacial osteogenic cells in mice elicits development of mandibular ossifying fibroma

Ossifying fibroma (OF) is a rare benign tumor of the craniofacial bones that can reach considerable and disfiguring dimensions if left untreated. Although the clinicopathological characteristics of OF are well established, the underlying etiology has remained largely unknown. Our work indicates that Men1-a tumor suppressor gene responsible of Multiple endocrine neoplasia type 1-is critical for OF formation and shows that mice with targeted disruption of Men1 in osteoblasts (Men1^Runx2Cre) develop multifocal OF in the mandible with a 100% penetrance. Using lineage-tracing analysis, we demonstrate that loss of Men1 arrests stromal osteoprogenitors in OF at the osterix-positive pre-osteoblastic differentiation stage. Analysis of Men1-lacking stromal spindle cells isolated from OF (OF-derived MSCs (OFMSCs)) revealed a downregulation of the cyclin-dependent kinase (CDK) inhibitor Cdkn1a, consistent with an increased proliferation rate. Intriguingly, the re-expression of Men1 in Men1-deficient OFMSCs restored Cdkn1a expression and abrogated cellular proliferation supporting the tumor-suppressive role of Men1 in OF. Although our work presents the first evidence of Men1 in OF development, it further provides the first genetic mouse model of OF that can be used to better understand the molecular pathogenesis of these benign tumors and to potentially develop novel treatment strategies.

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions

Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions.

Diagnosis and management of benign fibro-osseous lesions of the jaws: a current review for the dental clinician

Benign fibro-osseous lesions of the maxillofacial skeleton constitute a heterogeneous group of disorders that includes developmental, reactive (dysplastic) and neoplastic lesions. Although their classification has been reviewed multiple times in the past, the most common benign fibro-osseous lesions are fibrous dysplasia, osseous dysplasia and ossifying fibroma. For the dental clinician, the challenges involve diagnosis and treatment (or lack thereof). A careful correlation of all clinical, radiologic and microscopic features is essential to establish a proper diagnosis and a clear treatment plan. This article aimed to review the clinical, radiologic and histopathologic characteristics of benign fibro-osseous lesions of the jaws, with emphasis on their differential diagnoses. With a deeper understanding of benign fibro-osseous lesions, clinicians will be better prepared to manage these lesions in their practice.