Comprehensive Genomic Analysis of Cemento-Ossifying Fibroma.

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.

Odontogenic tumours in a Chilean population: a retrospective study of 544 cases based on 2022 WHO classification.

BACKGROUND: Odontogenic tumours are infrequent lesions. Studies on the frequency of odontogenic tumours from Latin America are scarce. This work aimed to determine the relative frequency of odontogenic tumours in a Chilean population using the 2022 World Health Organization classification. MATERIAL AND METHODS: This is a case series retrospective study. We reviewed 35,530 samples from 1975 to 2022 from the Oral Pathology Referral Institute and the Pathological Anatomy Service, Faculty of Dentistry, University of Chile. We utilized the 2022 World Health Organization classification for histological typification. RESULTS: According to 2022 World Health Organization classification, 544 odontogenic tumours were confirmed. The most frequent odontogenic tumours were: odontoma (n=241; 44.3%), ameloblastoma (n=109; 20.0%) and cemento-ossifying fibroma (n=71; 13.1%). Benign odontogenic tumours corresponded to 538 cases (98.9%) and malignant tumours were only six cases (1.1%). CONCLUSIONS: In our population, odontoma was the most frequent odontogenic tumour followed by ameloblastoma and cemento-ossifying fibroma. Malignant odontogenic tumours were very rare. The results of this study are similar to reports from America, but there are some differences concerning the data from Africa and Asia.

Quantitative proteomic study reveals differential expression of matricellular proteins between fibrous dysplasia and cemento-ossifying fibroma pathogenesis.

BACKGROUND: Fibrous dysplasia (FD) and cemento-ossifying fibroma (COF) are the most common gnathic fibro-osseous lesions. These diseases exhibit remarkable overlap of several clinicopathological aspects, and differential diagnosis depends on the combination of histopathological, radiographic, and clinical aspects. Their molecular landscape remains poorly characterized, and herein, we assessed their proteomic and phosphoproteomic profiles. METHODS: The quantitative differences in protein profile of FD and COF were assessed by proteomic and phosphoproteomic analyses of formalin-fixed paraffin-embedded tissue samples. Pathway enrichment analyses with differentially regulated proteins were performed. RESULTS: FD and COF exhibited differential regulation of pathways related to extracellular matrix organization, cell adhesion, and platelet and erythrocytes activities. Additionally, these lesions demonstrated distinct abundance of proteins involved in osteoblastic differentiation and tumorigenesis and differential abundance of phosphorylation of Ser61 of Yes-associated protein 1 (YAP1). CONCLUSIONS: In summary, despite the morphological similarity between these diseases, our results demonstrated that COF and DF present numerous quantitative differences in their proteomic profiles. These findings suggest that these fibro-osseous lesions trigger distinct molecular mechanisms during their pathogenesis. Moreover, some proteins identified in our analysis could serve as potential biomarkers for differential diagnosis of these diseases after further validation.

Concomitant bilateral mandibular cemento-ossifying fibroma and cementoblastoma: case report of an extremely rare occurrence.

BACKGROUND: Cemento-ossifying fibroma (COF) and cementoblastoma (CB) are rare benign odontogenic tumors with a predilection for the mandible. Cemento-ossifying fibroma is a fibro-osseous lesion that originates in the tooth bearing areas of jaw and shows cementum-like tissue in a fibrotic stroma. Cementoblastoma is classically related to roots of teeth with the presence of calcified cementum-like material. To date, only a single case of concomitant unilateral COF and CB has been reported in the literature. CASE PRESENTATION: We present an unusual case of a 37-year-old female who presented with two discrete bilateral swellings in the right and left mandible for 10 years. The larger tumor involved the left posterior mandible with extension anteriorly to the left and right anterior mandibles, and the smaller tumor was present in right posterior mandible. Radiology revealed two distinct lesions involving both sides of mandible. Histopathological examination showed characteristic features of cemento-ossifying fibroma in sections of the larger tumor and cementoblastoma in sections of smaller tumor. CONCLUSION: This case shows the very unique bilateral co-existence of COF and CB, the second case reported in literature to date.

Use of the Cover-Lifting Technique in Mandibular Cemento-Ossifying Fibroma Excision to Preserve the Inferior Alveolar Nerve.

Cemento-ossifying fibroma (also known as ossifying fibroma or cementifying fibroma) is a benign osteogenic neoplasm. Pain and paresthesia are rarely associated with cemento-ossifying fibroma; thus, nerves must be preserved during excision. With the advent of computer-aided techniques, the use of virtual surgical planning and a customized template can improve the precision of resection and reconstruction, reduce operating time, and improve postoperative outcomes. In this report, we describe a case of cemento-ossifying fibroma in a female patient who underwent segmental mandibulectomy and reconstruction with an iliac bone graft. Additionally, we describe a simple and effective way to preserve the inferior alveolar nerve.

[A painful periapical radiopacity in the lower jaw]. / Een pijnlijke periapicale radiopaciteit in de onderkaak.

A periapical radiopacity is frequently encountered by chance on a conventional periapical or panoramic x-ray. However, local pain and/or swelling in the area of a radiopacity is seldom seen. Here, we report on 2 cases of patients referred to the oral and maxillofacial surgeon with a painful periapical radiopacity in the lower jaw. The clinically and radiologically assumed diagnosis was a cementoblastoma, which was confirmed by histopathological examination following its surgical removal. A cementoblastoma is a rare, benign odontogenic tumor, mostly found in patients younger than 30. Treatment consists of surgical removal of the tumor, almost always together with the attached tooth. The recurrence rate after complete removal is approximately 12%. A cementoblastoma is clinically distinguished from other periapical radiopacities by local pain and sometimes swelling and radiologically by a relationship with the roots of a (pre)molar, a radiolucent rim surrounding the opacity, bone and/or root resorption and expansive growth.

Bringing benign ectomesenchymal odontogenic tumours to the lab: An in vitro study using an organotypic culture model.

BACKGROUND: Benign neoplasms exhibit most of the cellular phenomena considered hallmarks of cancer, except the capacity to metastasize. Thus, the elucidation of the mechanisms associated with the progression of benign neoplasms may complement and clarify the mechanisms involved in carcinogenesis. Benign odontogenic tumours often result in facial deformities and morbidities, and have complex pathogenesis, mainly due to the diversity of interactions between the odontogenic epithelium and the ectomesenchyme. Primary cell culture of such tumours is not only difficult to be established and maintained, but also tumour cells lose characteristic cellular morphology. Considering gene expression, growth, migration, proliferation and cellular morphology are controlled by cell-cell interactions and cell-extracellular matrix interactions, cell culture in 3D substrates has gained space as a way to overcome some of the limitations of traditional monolayer cell culture systems. METHODS: In this study, fragments obtained from mesenchymal odontogenic tumours were cultured in type I collagen scaffolds. Invasion tests were performed in these models, as well as phenotypic characterization of the cultured tumours. RESULTS: The results obtained for the odontogenic myxoma and the cemento-ossifying fibroma demonstrate a good reproduction of the growth pattern of these tumours under ex vivo conditions. Microscopic evaluation showed maintenance of cell viability in the explants for more than 30 days, without the presence of necrosis. CONCLUSION: This is the first study involving long-term 3D primary cultures of benign odontogenic tumours, which is expected to support complex approaches to cell and molecular biology, and to serve as an experimental model for testing molecular therapies.

Conservative Treatment of a Periapical Cementoblastoma: A Case Report.

Cementoblastoma is a rare benign odontogenic neoplasm of ectomesenchymal origin, accounting for fewer than 6% of all odontogenic tumors. Although the tumor characteristics are well known, the standard practice to treat this lesion is surgical excision and extraction of the affected tooth, with few reported cases using a tooth-conservative treatment approach. This report presents the case of a 33-year-old woman with cementoblastoma who underwent conservative treatment to preserve her tooth in the oral cavity. Endodontic treatment of the tooth was performed; 30 days later, the lesion was removed with the apical third of the root of the tooth. After 7 years of follow-up, no recurrence was observed, and the tooth retains its masticatory function. In certain cases of cementoblastoma, the affected tooth can be kept in the oral cavity instead of being extracted, thereby preserving the oral health of patients.

Retrospective Study of 383 Cases of Fibro-Osseous Lesions of the Jaws.

PURPOSE: The aims of this study were to describe the clinical and radiologic features of 383 fibro-osseous lesions (FOLs) from an oral pathology reference service in Brazil and to compare the findings with previous studies. The hypothesis of the study was that the most common type of FOL would differ from other investigations. MATERIALS AND METHODS: We conducted a descriptive and retrospective study with review of the records of the clinical and biopsy services (1990 to 2015). All records of the patients included showed a definitive diagnosis of FOL. The primary outcome variable was the type of FOL, and the predictor variables were gender, age, ethnicity, location, and clinical and radiologic characteristics. Descriptive analyses and χ2 tests were performed. The P value was set at .05. RESULTS: From the 27,998 records available, 383 showed FOLs, with 187 (48.8%) being cemento-osseous dysplasias (CODs), 103 (26.9%) being fibrous dysplasias (FDs), and 93 (24.3%) being ossifying fibromas (OFs). The mean age of the patients was 38.5 ± 17.5 years. CODs presented a predilection for female gender (n = 314, 82.0%), African descent (n = 134, 71.6%), and the mandible (n = 248, 64.6%). The most common radiologic feature was a mixed radiolucent-radiopaque image (n = 149, 51.7%). FDs and OFs were commonly diagnosed during the first and second decades of life (P < .001), whereas CODs were more frequently diagnosed beyond the third decade (P < .001). Secondary osteomyelitis was more significantly observed in CODs (P < .001) than in FDs and OFs. Swelling was more frequently reported for FDs and OFs than for CODs (P < .001). CONCLUSIONS: CODs were the most frequently observed FOLs in this Brazilian population. Female patients, patients of African descent, and patients with mandibular localization were most commonly affected by these conditions. The most common type of FOL differed from that in similar case reports or series from various geographic locations. It is believed that the data source (clinical and/or biopsy services) can directly influence the outcome.

Protection of Inferior Alveolar Neurovascular Bundle in Alveolar Bone Operation.

PURPOSE: The aim of this study was to investigate the protection of the inferior alveolar neurovascular bundle in alveolar bone operation in conditions such as chronic osteomyelitis and cementoma. PATIENTS AND METHODS: The study enrolled 7 cases, 4 with chronic osteomyelitis and 3 with cementoma with pain. Computed tomography scan and 3-dimensional reconstruction were performed for the diseases. Data were processed by ProPlan CMF 1.3 software. The edge of lesion was defined and the inferior alveolar nerve was marked. Template was designed to guide the osteotomy line. Piezosurgery was used for osteotomy, with the avoidance of nerve canal. Current perception threshold (CPT) was performed to evaluate the nerve function after operation. RESULTS: The CPT difference of the affected side before and after operation showed no statistically significant differences compared with that of the unaffected side (P = 0.0556). CONCLUSIONS: Digital template protects the inferior alveolar neurovascular bundle with the aid of piezosurgery during alveolar bone resection, which obtained satisfying clinical results. As powerful assistive tools of functional surgery, digital template and piezosurgery achieve both the purposes of treatment and function.

Juvenile Ossifying Fibroma of Maxilla.

Ossifying fibroma (OF) is a rare, benign, non-odontogenic tumor of the jaw which comes under the group of fibro-osseous lesions. Ossifying fibromas of the mandible are more common than in the maxillary region. Juvenile ossifying fibroma has been distinguished from conventional ossifying fibroma on the basis of patient's age, site predilection, and clinical behavior. The lesion should be differentiated from other fibro-osseous lesions as its management varies from surgical enucleation to complete resection. Present report describes the case of juvenile ossifying fibroma of anterior maxillary region in a 7 year old male patient, with a detailed description of clinical, radiographic, histopathologic features, and its surgical management.

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.

Can Differences in Vascularity Serve as a Diagnostic Aid in Fibro-Osseous Lesions of the Jaws?

PURPOSE: Different lesions in the fibro-osseous group share microscopic features; thus, establishing a definitive diagnosis based on microscopic features alone can be a challenge. There is a need for additional microscopic tools to aid in differentiating these lesions. This study compared parameters related to vascularity among 3 lesions in the fibro-osseous group: fibrous dysplasia (FD), central ossifying fibroma (COF), and cemento-osseous dysplasia (COD). MATERIALS AND METHODS: This study was a cross-sectional analysis of biopsied lesions retrieved from 3 medical centers over a 14-year period. The primary predictor variables were the vascularity parameters (number, perimeter, and area). The outcome variables were diagnoses of FD, COF, and COD. Diagnosis was based on clinical, microscopic, and radiologic correlations. From each histopathologic slide, 5 representative fields were captured with a computerized digital camera. The number of blood vessels was counted, and the surface area and vascular perimeter were measured by tracing the perimeter of each vessel. Data were statistically analyzed using analysis of variance with logarithmic transformation and a Tukey adjustment. RESULTS: Sixty-six cases were included in the study (26 in FD group, 26 in COF group, and 14 in COD group). The mean number of vessels showed only a tendency to be larger in the FD group compared with the COF and COD groups (5.4 ± 2.6, 3.7 ± 2.3, and 3.6 ± 1.7, respectively), but the results did not reach the threshold for significance. The mean vascular perimeter was 1,385.8 ± 859.2 pixels in the FD group and 742.6 ± 661.8 in COF group after logarithmic transformation (P = .012). The perimeter in the COD group was smaller (941.1 ± 502) compared with that in the FD group, but the difference did not reach the threshold for significance. The mean area was 25,061 ± 24,875.6 in the FD group and 11,773.8 ± 21,734.4 in the COF group after logarithmic transformation (P = .004). The perimeter in the COD group was smaller (13,011.1 ± 8,338.3) compared with the FD group, but the difference did not reach the threshold for significance. CONCLUSION: The vascular content of the FD group was markedly higher than of the COF group. These vascular changes can aid in differentiating these lesions microscopically.

Cementoma of the calcaneus: a case report.

BACKGROUND: The cementoma is a common disease of the dental root apex, which generally occurs in the maxilla and the mandible, but the cementoma occurring in the long bone is rare. Moreover, the incidence of cementoma in the calcaneus is extremely infrequent. CASE PRESENTATION: The present study reports an unusual case of a 19-year-old girl, who complained of pain in the left heel. Subsequent radiographs and computed tomography (CT) were used in the diagnosis. The imaging features of the lesion included a radiopaque matrix and radiolucent tissue, particularly an arc-shaped fat band. An excisional biopsy was performed. Histopathological examination confirmed the diagnosis of cementoma in the calcaneus. After the operation, the patient was followed up without recurrence. CONCLUSIONS: Imaging examination plays an important role in the differential diagnosis of cementoma of the calcaneus.

Giant Cementoblastoma Of Left Maxilla Involving A Deciduous Molar.

Cementoblastoma is a relatively rare benign tumour. The clinicopathologic features, radiological findings, treatment and prognosis are reported here in a 10-year-old girl who presented to us from Afghanistan. The tumor was managed surgically and the histopathology confirmed the diagnosis of cementoblastoma. There was no evidence of recurrence at one year of follow up.

Peripheral Cemento-Ossifying Fibroma.

Peripheral cemento-ossifying fibroma (PCOF), a relatively uncommon lesion, reactive in nature is seen as an overgrowth of the gingival tissues often leading to periodontal problems. It is a benign tumor with slow-growing potential commonly affecting the anterior maxilla whose pathogenesis till date is uncertain. It is usually challenging to diagnose peripheral cemento-ossifying fibroma based on clinical observation and examination, hence histopathological examination is mandatory to arrive at an accurate diagnosis. Recurrence of the lesion is common unless and until it is completely excised. We present the report of two cases of peripheral cemento-ossifying fibroma of our department, complaining of a mass in the gingiva of posterior maxilla and mandible.

[Radiolucent and opaque lesions on a panoramic radiograph; a cyst or not?] / Radiolucente en opake laesies op de panoramische röntgenopname; wel of geen cyste?

In the context of pain diagnostics, several lesions, partially radiolucent and partially opaque, were identified by chance in the mandible and maxilla. On the basis of the characteristic x-ray image, it was assumed to be cemento-osseous dysplasia. At an early stage, this cannot easily be distinguished from apical periodontitis. An incorrect diagnosis could lead to needless endodontic treatment.

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

Currently, central cemento-ossifying fibroma is classified by the World Health Organization as a primary bone-forming tumor of the jaws. However, histopathologically, it is often indistinguishable from cemento-osseous dysplasias in that it forms osteoid and cementicles (cementum droplets) in varying proportions. It is believed that pluripotent cells within the periodontal membrane can be stimulated to produce either osteoid or woven bone and cementicles when stimulated. If this is true, cemento-ossifying fibroma would be better classified as a primary odontogenic neoplasm arising from the periodontal ligament. Cemento-ossifying fibromas also do not occur in the long bones. The present report compares several entities that fall within the diagnostic realm of benign fibro-osseous lesions and reviews the evidence for reclassifying central cemento-ossifying fibroma as a primary odontogenic neoplasm.

Periapical cemento-osseous dysplasia: a case report with twelve-year follow-up and review of literature.

AIM: To present a case report describing the long-term behaviour of periapical cemento-osseous dysplasia by observing the radiographic changes that took place over a period of 12 years. A review of the pertinent literature is also presented. SUMMARY: A healthy 26-year-old white female was referred to the Wilford Hall USAF Medical Center Endodontic Department for evaluation of an asymptomatic radiolucency at the apex of the right mandibular lateral incisor. Following a clinical evaluation that included pulp testing, a diagnosis of periapical cemento-osseous dysplasia (PCOD) was made. No treatment was rendered but follow-up visits were recommended. The patient was subsequently re-evaluated 8 times over a period of 12 years. During that time the lesion changed in appearance, displaying the various phases of PCOD. At the same time, lesions affecting the three adjoining incisors appeared and behaved in a similar manner. At the 12-year recall, the right lateral and both central incisors revealed no evidence of PCOD and an almost normal trabecular pattern of bone could be seen. Misdiagnosis and unnecessary treatment of PCOD may be avoided with careful pulp testing and knowledge of its most common locations of occurrence, radiographic appearances (phases) and benign behaviour.