New tumour entities in the 4th edition of the World Health Organization Classification of Head and Neck tumours: odontogenic and maxillofacial bone tumours

Florid cemento-osseous dysplasia: A case report and review of literature

Florid cemento-osseous dysplasia (FCOD) is a benign slowly growing fibro-osseous disorder, usually diagnosed accidentally through routine radiographic examination. The lesions are generally asymptomatic, but, in the most severe cases, focal enlargement and pain may occur due to infection. Here, we report the rare case of a Caucasian middle-aged woman showing, at orthopantomography performed during routine dental check-up, the presence of multiple symmetrical, dense and lobulated radiopaque bone lesions in several areas of the jaws, surrounded by a radiolucent border. The lesions were asymptomatic. Histologically, the replacement of healthy bone by metaplastic bone and fibrous tissue, typical of FCOD, was observed. The lesion remained painless, clinically and radiologically stable over two years follow-up. In asymptomatic cases, no treatment is required, but active clinical and radiographic follow-up are recommended at long-term, to reduce the risk of dental infections and oral surgery involving the area of the lesion. The avascular nature of FCOD contributes to susceptibility to severe infection, bone sequestration and osteomyelitis, limiting the in-site penetration of the antibiotics. Therefore, a careful clinical and radiographic monitoring of the lesions is recommended together with periodical dental check-up.

Factors and management techniques in odontogenic keratocysts: a systematic review

OBJECTIVES

Odontogenic keratocysts exhibit frequent recurrence, distinctive histopathological traits, a tendency towards aggressive clinical behavior, and a potential linkage to the nevoid basal cell carcinoma syndrome. The aim of this systematic review is to compile insights concerning the control of this condition and assess the effectiveness of various treatment approaches in reducing the likelihood of recurrence.

MATERIALS AND METHODS

The following systematic review adhered to the PRISMA guidelines. The systematic revision was registered on PROSPERO and  structured around the questions related to the population, intervention, control, outcome and study design (PICOS).

RESULTS

After conducting a search on the PubMed database, we initially identified 944 records. After using end-note software to remove duplicate entries, results totally with 462 distinct records. A thorough review of the titles and abstracts of these articles led to the selection of 50 papers for in-depth examination. Ultimately, following the application of our eligibility criteria, we incorporated 11 articles into our primary outcome analysis.

CONCLUSION

Among the studies examined, the most common location for these lesions was found to be in the area of the mandibular ramus and the posterior region of the mandible. In cases where the exact location wasn't specified, the mandible emerged as the predominant site. When we considered the characteristics of these lesions in studies that mentioned locularity, most were described as unilocular in two studies, while in two other studies, the prevalence of multilocular lesions was observed. Risk factors associated with keratocyst recurrence include younger patient age, the presence of multilocular lesions, larger lesion size, and a longer anteroposterior dimension. Certain treatment methods have demonstrated a lack of relapses. These include the use of 5-fluorouracil, marsupialization, enucleation with peripheral ostectomy or resection, enucleation and curettage, as well as resection without creating continuity defects. However, it is important to note that further research is essential. Prospective studies and randomized trials are needed to collect more comprehensive evidence regarding the effectiveness of various treatment approaches and follow-up protocols for managing odontogenic keratocysts.

CLINICAL RELEVANCE

Odontogenic keratocysts still enter into differential diagnoses with other lesions that affect the jaw bones such as ameloblastama and other tumor forms, furthermore it is not free from recurrence, therefore the therapeutic approach to the lesion aimed at its elimination can influence both the possible recurrence and complications, knowledge of the surgical methods that offer the most predictable and clinically relevant result for the management of follow-up and recurrences.

Challenging pitfalls in frozen section pathology: a case of mandible ghost cell odontogenic carcinoma and the literature review

BACKGROUND

Ghost cell odontogenic carcinoma (GCOC) is a rare malignancy characterized by the presence of ghost cells, preferably in the maxilla. Only slightly more than 50 case reports of GCOC have been documented to date. Due to the rarity of this tumor and its nonspecific clinical criteria, there is a heightened risk of misdiagnosis in clinical examination, imaging findings, and pathology interpretation.

CASE PRESENTATION

A 50-year-old male patient presented to the hospital due to experiencing pain in his lower front teeth while eating for the past 2 months. Upon examination, a red, hard, painless mass was found in his left lower jaw, measuring approximately 4.0 cm × 3.5 cm. Based on the malignant histological morphology of the tumor and the abundant red-stained keratinized material, the preoperative frozen section pathology misdiagnosed it as squamous cell carcinoma (SCC). The surgical resection specimen pathology via paraffin section revealed that the tumor was characterized by round-like epithelial islands within the fibrous interstitium, accompanied by a large number of ghost cells and some dysplastic dentin with infiltrative growth. The malignant components displayed marked heterogeneity and mitotic activity. Additionally, a calcified cystic tumor component of odontogenic origin was observed. Hemorrhage, necrosis, and calcifications were present, with a foreign body reaction around ghost cells. Immunoreactivity for β-catenin showed strong nuclear positivity in tumor cells, while immunostaining was completely negative for p53. The Ki67 proliferation index was approximately 30-40%. The tumor cells exhibited diffuse CK5/6, p63, and p40 immunoreactivity, with varying immunopositivity for EMA. Furthermore, no BRAFV600E mutation was identified by ARMS-PCR. The final pathology confirmed that the tumor was a mandible GCOC.

CONCLUSION

We have reported and summarized for the first time the specific manifestations of GCOC in frozen section pathology and possible pitfalls in misdiagnosis. We also reviewed and summarized the etiology, pathological features, molecular characteristics, differential diagnosis, imaging features, and current main treatment options for GCOC. Due to its rarity, the diagnosis and treatment of this disease still face certain challenges. A correct understanding of the pathological morphology of GCOC, distinguishing the ghost cells and the secondary stromal reaction around them, is crucial for reducing misdiagnosis rates.

A Retrospective Analysis of 129 Ameloblastoma Cases: Clinical and Demographical Trends from a Single Institution

Ameloblastomas are benign neoplasms of the jaw, but frequently require extensive surgery. The aim of the study was to analyze the demographic and clinicopathological features of ameloblastoma cases at a single Oral and Maxillofacial Surgery group in the United States.

STUDY DESIGN

A retrospective chart review of patients evaluated for ameloblastoma between 2010 and 2020 at a single tertiary care center. Age, race, sex, tumor size, tumor location, and histological subtypes were recorded.

RESULTS

A total of 129 cases of ameloblastoma were recorded with a mean patient age of 42 ± 18.6 years (range 9-91 years old), male to female ratio 1.08:1. Ameloblastoma presenting in the mandible outnumbered maxilla in primary (118 to 8, respectively) and recurrent cases (8 to 1, respectively). There was a higher prevalence of ameloblastoma in Black patients (61.3%) with mean age of Black patients occurring at 40.5 years and the mean age of White patients occurring at 47.8 years and mean tumor size trended larger in the Black patients (15.7 cm2) compared to White patients (11.8 cm2).

CONCLUSION

Data suggests a strong influence of racial factors on the incidence of ameloblastoma, with regards to size, Black patients with ameloblastoma trended higher and more data is needed to clearly elucidate any relationship between the tumor size and race, as other factors may influence the size (such as time to discovery).

Expression Profiling of EMT Transcriptional Regulators ZEB1 and ZEB2 in Different Histopathological Grades of Oral Squamous Cell Carcinoma Patients

Background

Pakistan has a high burden of oral cancers, with a prevalence rate of around 9%. Oral Squamous Cell Carcinoma (OSCC) accounts for about 90% of oral cancer cases. Epithelial to Mesenchymal Transition (EMT) gets highly stimulated in tumor cells by adopting subsequent malignant features of highly invasive cancer populations. Zinc Finger E-Box binding factors, ZEB1 and ZEB2, are regulatory proteins that promote EMT by suppressing the adherent ability of cells transforming into highly motile cancerous cells. The present study aimed to analyze the expression of EMT regulators, ZEB1 and ZEB2, and their association with the clinicopathological features in different grades of OSCC patients.

Methods

Tissue samples were collected for both case and control groups from the recruited study participants. Cancer tissues (cases) were collected from the confirmed OSCC patients, and healthy tissues (controls) were collected from third-molar dental extraction patients. The study participants were recruited with informed consent and brief demographic and clinical characteristics. The case group was further segregated with respect to the histological cancer grading system into well-differentiated (WD), moderately differentiated (MD), and poorly differentiated (PD) squamous cell carcinoma (SCC) groups. RNA was extracted from the tissue samples for expression profiling of ZEB1 and ZEB2 genes through quantitative real-time PCR (qRT-PCR).

Results

All of the recruited participants had a mean age of 46.55 ± 11.7 (years), with most of them belonging to Urdu speaking ethnic group and were married. The BMI (kg/m2) of the healthy participants was in the normal range (18-22 kg/m2). However, BMI was found to be reduced with the proliferation in the pathological state of cancer. The oral hygiene of patients was better than the healthy participants, possibly due to the strict oral hygiene practice concerns of consultants. Every recruited OSCC patient had one or multiple addiction habits for more than a year. Patients reported health frailty (46.6%), unhealed mouth sores (40%), swallowing difficulties and white/reddish marks (80%), and restricted mouth opening (64.4%). Furthermore, 82.2% of the recruited patients observed symptoms within 1-12 months, and buccal mucosa was the most exposed tumor site among 55.6% of the patients. Expression profiling of EMT regulators showed gradual over-expressions of ZEB1 (8, 20, and 42 folds) and ZEB2 (4, 10, and 18 folds) in respective histological cancer grades.

Conclusion

High expressions of ZEBs have been significantly associated with cancer progression and poor health. However, no association was found between OSCC with other clinicopathological features when compared to healthy controls.

Imaging of Fibro-osseous Lesions and Other Bone Conditions of the Jaws

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.

Unicystic ameloblastoma: A retrospective study on recurrent factors from a single institute database

OBJECTIVE

Unicystic ameloblastomas are a variant of ameloblastoma with a definite recurrence rate because of the biological behaviours of the tumour. The risk factors associated with disease recurrence were analysed in this retrospective study.

METHODS

A total of 132 patients with primary unicystic ameloblastoma reported in a tertiary hospital from 2005 to 2015 were analysed to identify the clinic-pathological and radiological factors associated with recurrence using univariate and multivariate Cox regression analyses.

RESULTS

The mean volume was 30.54cm3 ± 12.55 cm3, and this value differed significantly according to recurrence (p < 0.001). Root resorption and bone cortex/soft tissue invasion were also significantly associated with recurrence among unicystic ameloblastoma patients (p = 0.017 vs. p < 0.001, respectively). A new stage classification system was developed to predict disease recurrence of patients. The multivariate Cox regression analysis revealed that the new stage classification system was the only predictor of disease recurrence in unicystic ameloblastoma patients (p < 0.001), regardless of root resorption, position and site characteristics.

CONCLUSIONS

Volume, root resorption and bone cortex/soft tissue invasion were risk factors for disease recurrence among unicystic ameloblastoma patients. The new stage classification was an independent predictor of disease recurrence in patients with unicystic ameloblastoma.

Developing Odontoma in the Mandible of an Eight-Year-Old Boy

Benign mixed odontogenic tumors have been repeatedly classified and reclassified over the past few decades. Odontoma is considered a hamartoma due to its slow growth and non-aggressive nature. We present an interesting case of developing odontoma in an eight-year-old boy. His complaint was a slow-growing swelling in the lower right back tooth region. Clinical examination revealed a carious deciduous second molar. The orthopantomogram revealed a well-defined radiolucency around the unerupted mandibular first premolar and impacted mandibular second premolar. Histopathology revealed an odontogenic epithelial lining overlying myxofibrous stroma with inflammatory cells and calcified structures with few odontogenic rests. Special staining methods including Van Gieson and modified Gallego stains led to the final diagnosis of a developing odontoma.

Odontogenic Keratocyst With Moderate Epithelial Dysplasia: A Rare Entity

We present a rare case of odontogenic keratocyst (OKC) with moderate epithelial dysplasia in a 47-year-old male patient. He presented with a history of pain and swelling on the right side of his face for the past three months. The radiograph revealed multi-locular radiolucency involving the ramus, coronoid process, and condylar process of the right mandible. We have discussed the cytology, incisional biopsy, radiological investigations, surgical management, reconstruction, excisional biopsy report, and follow-up of this rare entity.

High-grade osteosarcoma arising in DCIA flap reconstruction after a prior resection of maxillar cemento-ossifying fibroma: A case report

Cemento-ossifying fibroma is a rare benign odontogenic tumour of the tooth-bearing jaws. Its concomitant occurrence with osteosarcoma, a malignant maxillofacial bone tumour, has never been described before. We present an uncommon case of a 43-year-old woman in whom a cemento-ossifying fibroma in the right maxilla was treated by resection and reconstruction using a deep circumflex iliac artery flap. During surgical prosthetic rehabilitation one-year post-operative, an osteosarcoma extending from the contralateral maxilla was coincidentally discovered in the deep circumflex iliac artery flap. The aim of this case report is to raise awareness on the extremely rare but possible simultaneous and independent occurrence of a cemento-ossifying fibroma and an osteosarcoma.

Collision Tumour Comprising Desmoplastic Ameloblastoma and Squamous Odontogenic Tumour in the Anterior Maxilla: A Case Report

Collision tumours, characterized by the simultaneous occurrence of two distinct neoplasms within the same anatomical site, are exceedingly rare in oral pathology. This case report presents an uncommon collision tumour involving desmoplastic ameloblastoma and squamous odontogenic tumour in the anterior maxilla of a 52-year-old male from the Indian population. Desmoplastic ameloblastoma is a variant of ameloblastoma known for its unique histopathological features, while squamous odontogenic tumour is a benign epithelial odontogenic tumour with distinctive clinical behaviour. The rarity of this occurrence emphasizes the need for accurate diagnosis and effective treatment strategies. This report discusses the clinical presentation, radiographic findings, and histopathological characteristics of this collision tumour. Through the presentation of this case, we aim to contribute to the understanding of these rare entities and their management considerations.

Sclerosing odontogenic carcinoma misnomering previously as central odontogenic fibroma-A case report with review of literature

Sclerosing odontogenic carcinoma (SOC) was first described by Koutlas et al. in 2008. Despite its inclusion in the World Health Organization (WHO) as a distinct entity, it is a tumour that remains poorly defined in the literature, with only 10 reported cases to date. The mandibular premolar and molar region is more commonly affected compared to the maxilla. In the maxilla, the anterior and the molar regions are most commonly affected. This article describes a case report of a Sclerosing Odontogenic Carcinoma in a 50 year old male patient in the mandibular region. The radiograph showed a well-defined radiolucency extending from the left ramus of the mandible to the right lower molar region. SOC is low grade with mild atypia and frequent mitosis and diffused infiltrative and perineural spread.

Ameloblastoma of the Mandible in a 16-Year-Old Female-Case Report

Ameloblastoma is a benign epithelial tumor that has aggressive, destructive and unlimited growth potential, having the capacity for recurrence and malignant transformation. Regarding the symptoms and clinical signs, the presentation of ameloblastoma is poor. In children and young people, ameloblastoma can be difficult to diagnose, because it mimics other benign lesions. Its diagnosis requires a combination of imaging data, histopathological analysis and molecular tests. The methods of treatment consist of radical surgery (segmental resection) and conservative treatments (enucleation with bone curettage). The particularity of the presented case is represented by the late request for medical consultation, a direct consequence of the measures implemented to prevent and control the spread of COVID-19.

A retrospective study of the malignant change of odontogenic keratocyst

The odontogenic keratocyst (OKC) is a common cystic lesion of the maxilla and mandible. Squamous cell carcinoma (SCC) arising from OKC or dysplasia occurring in OKC is rare. This study aimed to explore the incidence and clinical features of the dysplasia and malignant transformation of OKC. In this study, 544 patients diagnosed with OKC were collected. Among them, 3 patients were diagnosed as SCC arising from OKC, and 12 patients were diagnosed as OKC with dysplasia. The incidence was calculated. Clinical features were analyzed by chi-square test. In addition, a representative case reconstructing mandible with vascularized fibula flap under general anesthesia was reported. And cases reported before were reviewed. The incidence of the dysplasia and malignant transformation of OKC, which are highly associated with the clinical features of swelling and chronic inflammation, is about 2.76%. But the relevance between the dysplasia and malignant transformation and age, gender together with pain is not statistically high. All in all, the clinical features of swelling and chronic inflammation can be considered as characteristics of the dysplasia and malignant transformation of OKC. Although the pain isn't statistically relevant, it may be a dangerous clew. Also, combined with earlier literatures, the dysplasia and malignant transformation of OKC shows unique features of radiographs and histopathology.

Cemento-ossifying fibroma resection combined with heterotopic canine autotransplantation: a case report

Cemento-ossifying fibroma (COF) is a mesenchymal benign odontogenic tumor, which may lead to impacted or ectopic permanent teeth. Autotransplantation of teeth is a surgical process, in which a tooth is transplanted from one position to another in the same individual. This method can effectively restore the patient's mastication and aesthetics and is feasible in replacing missing teeth. This study reports a case of simultaneous COF resection combined with heterotopic canine autotransplantation to repair dentition defect, which effectively promotes the restoration of bone continuity and stability and achieves immediate and long-term aesthetic function requirements.

MXene-Integrated Silk Fibroin-Based Self-Assembly-Driven 3D-Printed Theragenerative Scaffolds for Remotely Photothermal Anti-Osteosarcoma Ablation and Bone Regeneration

Aiming to address the bone regeneration and cancer therapy functionalities in one single material, in this study, we developed a dual-functional theragenerative three-dimensional (3D) aerogel-based composite scaffold from hybridization of photo-cross-linked silk fibroin (SF) biopolymer with MXene (Ti3C2) two-dimensional (2D) nanosheets. To fabricate the scaffold, we first develop a dual-cross-linked SF-based aerogel scaffold through 3D printing and photo-cross-linking of the self-assembly-driven methacrylate-modified SF (SF-MA) gel with controlled pore size, macroscopic geometry, and mechanical stability. In the next step, to endow a remotely controlled photothermal antiosteosarcoma ablation function to fabricated aerogel scaffold, MXene 2D nanosheets with strong near-infrared (NIR) photon absorption properties were integrated into the 3D-printed scaffolds. While 3D-printed MXene-modified dual-cross-linked SF composite scaffolds can mediate the in vitro growth and proliferation of preosteoblastic cell lines, they also endow a strong photothermal effect upon remote irradiation with NIR laser but also significantly stimulate bone mineral deposition on the scaffold surface. Additionally, besides the local release of the anticancer model drug, the generated heat (45-53 °C) mediated the photothermal ablation of cancer cells. The developed aerogel-based composites and chosen therapeutic techniques are thought to render a significant breakthrough in biomaterials' future clinical applications.

Pediatric Oral Pathology: Odontogenic Cysts

Cysts encountered in the head and neck typically arise from epithelium that would normally be programmed to form teeth or tooth-supporting structures (odontogenic epithelium). These cysts come with a confusing array of similar-sounding names and histopathologic features that are sometimes shared between conditions. Here we describe and contrast the relatively-common lesions: hyperplastic dental follicle, dentigerous cyst, radicular cyst, buccal bifurcation cyst, odontogenic keratocyst, glandular odontogenic cyst, and the less-common gingival cyst of the new-born and thyroglossal duct cyst. The goal of this review is to help clarify and simplify these lesions for the general pathologist, pediatric pathologist, and surgeon.

Clinico-pathological and prognostic overview of metastasizing ameloblastoma: An overview of the systematic reviews

Background

Metastasizing Ameloblastoma (MA) is an aggressive variant of ameloblastoma (AM) with the ability to metastasize without cytological malignant changes. Thus it aims to comprehensively review the clinico-pathological and prognostic aspects of MA through integration of current literature.

Methods

Electronic searches were conducted in PubMed-MEDLINE, Scopus, Web of Science and Google Scholar. Two independent reviewers screened abstracts and evaluated paper eligibility. AMSTAR2 checklist was used to assessed methodological quality of included systematic reviews (SRs).

Results

From 390 initial papers, 279 underwent eligibility screening, with five systematic reviews (SRs) meeting inclusion criteria. Six hundred sixty-one MA cases were found in five SRs that were included. MA predominantly affects men, exhibits mandible preference, and occurs in individuals in their fourth or fifth decade. Benign metastatic deposits commonly manifest in lungs and lymph nodes. Distant metastasis probability rises with multiple recurrences and incomplete surgical removal. Tumor recurrence and metastasis unfavorably impact clinical outcomes. Quality of evidence assessment was absent across SRs; four SRs were critically low in methodological quality.

Conclusions

AM's metastatic potential lacks predictability. Early/multiple recurrences post-treatment may signal poor prognosis, warranting vigilant follow-up. Methodical analysis of each AM case is imperative to comprehend the metastatic-benign histology relationship.

Pediatric Odontogenic Tumors

Odontogenic tumors are rare tumors of the jaws that arise from remnants of the tooth forming apparatus. Some odontogenic tumors demonstrate strong predilection for pediatric patients including the unicystic ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma, ameloblastic fibro-odontoma, odontoma, and primordial odontogenic tumor. In this review, we discuss the clinical, radiographic, histopathologic, and molecular characteristics of select odontogenic tumors that demonstrate pediatric predilection and review management.

Primordial Odontogenic Tumor; Archival Review of 19380 Cases in a 55-Year Retrospective Study

BACKGROUND AND OBJECTIVE

Primordial odontogenic tumor is a rare odontogenic tumor reported for the first time in 2014. It was included in the latest edition of World Health Organization classification of Head and Neck Tumors as a new benign mixed epithelial-mesenchymal neoplasm. To date, 26 cases has been reported in literature. The aim of this study was to determine the possible presence of primordial odontogenic tumor in the previously diagnosed cases with myxoid stroma.

MATERIALS AND METHODS

This study was a retrospective descriptive study that was concluded in Oral and Maxillofacial Pathology Department, School of Dentistry, Tehran University of Medical Sciences. We reviewed all 19,380 cases from 19,66 to find the lesions with myxoid stroma which were in differential diagnosis with primordial odontogenic tumor. These cases should be associated with an impacted or unerupted tooth and belong to the patients under 20 years old.

RESULTS

We find 503 pericoronal lesions with myxoid stroma. Three cases were isolated after recut and reevaluation for finding fulfill histologic features. After immunohistochemical analysis, we find a new case of developing primordial odontogenic tumor associated with odontoma.

DISCUSSION

Primordial odontogenic tumor a recently described odontogenic tumor has a well-defined clinicopathological and immunohistochemical profile and should be differentiated from the others pericoronal lesions. It is the first time that this archival review has been done to find probable cases of primordial odontogenic tumor.

A Current Review of Machine Learning and Deep Learning Models in Oral Cancer Diagnosis: Recent Technologies, Open Challenges, and Future Research Directions

Cancer is a problematic global health issue with an extremely high fatality rate throughout the world. The application of various machine learning techniques that have appeared in the field of cancer diagnosis in recent years has provided meaningful insights into efficient and precise treatment decision-making. Due to rapid advancements in sequencing technologies, the detection of cancer based on gene expression data has improved over the years. Different types of cancer affect different parts of the body in different ways. Cancer that affects the mouth, lip, and upper throat is known as oral cancer, which is the sixth most prevalent form of cancer worldwide. India, Bangladesh, China, the United States, and Pakistan are the top five countries with the highest rates of oral cavity disease and lip cancer. The major causes of oral cancer are excessive use of tobacco and cigarette smoking. Many people’s lives can be saved if oral cancer (OC) can be detected early. Early identification and diagnosis could assist doctors in providing better patient care and effective treatment. OC screening may advance with the implementation of artificial intelligence (AI) techniques. AI can provide assistance to the oncology sector by accurately analyzing a large dataset from several imaging modalities. This review deals with the implementation of AI during the early stages of cancer for the proper detection and treatment of OC. Furthermore, performance evaluations of several DL and ML models have been carried out to show that the DL model can overcome the difficult challenges associated with early cancerous lesions in the mouth. For this review, we have followed the rules recommended for the extension of scoping reviews and meta-analyses (PRISMA-ScR). Examining the reference lists for the chosen articles helped us gather more details on the subject. Additionally, we discussed AI’s drawbacks and its potential use in research on oral cancer. There are methods for reducing risk factors, such as reducing the use of tobacco and alcohol, as well as immunization against HPV infection to avoid oral cancer, or to lessen the burden of the disease. Additionally, officious methods for preventing oral diseases include training programs for doctors and patients as well as facilitating early diagnosis via screening high-risk populations for the disease.

Self-Assembly-Driven Bi2S3 Nanobelts Integrated a Silk-Fibroin-Based 3D-Printed Aerogel-Based Scaffold with a Dual-Network Structure for Photothermal Bone Cancer Therapy

Multifunctional all-in-one biomaterial combining the therapeutic and regeneration functionalities for successive tumor therapy and tissue regeneration is in high demand in interdisciplinary research. In this study, a three-dimensional (3D) aerogel-based composite scaffold with a dual-network structure generated through self-assembly and photo-cross-linking with combined properties of photothermally triggered controlled anticancer drug release and photothermal cancer cell ablation was successfully fabricated. The fabrication of composites consists of self-assembly of a silk fibroin methacrylate (SF-MA) biopolymer incorporated with hydrothermally driven bismuth sulfide (Bi₂S₃) methacrylate nanobelts, followed by a photo-cross-linking-assisted 3D-printing process. The developed scaffolds presented hierarchically organized porosity and excellent photothermal conversion thanks to the strong near-infrared (NIR) photon absorption of incorporated Bi₂S₃ nanobelts inside the scaffold matrix. The heat generated in the scaffold mediated by laser irradiation has not only triggered controlled and prolonged release of the anticancer drug but also significantly ablated the bone cancer cells adhered on the scaffold. In addition, the developed 3D composite scaffolds have demonstrated excellent biodegradability for organic and inorganic network constituents at different media, enabling them as potential implants to be replaced by de novo tissue. In combination of chemotherapy and photothermal therapy, the multifunctional 3D-printed composite aerogel scaffold is expected to be an excellent implantable material in bone tissue engineering (BTE) for successive cancer therapy and tissue regeneration.

Sclerosing odontogenic carcinoma of maxilla: A case report

BACKGROUND

Sclerosing odontogenic carcinoma is a rare primary intraosseous neoplasm that was featured recently as a single entity in the World Health Organization classification of Head and Neck Tumors 2017, with only 14 cases published to date. The biological characteristics of sclerosing odontogenic carcinoma remain indistinct because of its rarity; however, it appears to be locally aggressive, with no regional or distant metastasis reported to date.

CASE SUMMARY

We reported a case of sclerosing odontogenic carcinoma of the maxilla in a 62-year-old woman, who presented with an indolent right palatal swelling, which progressively increased in size over 7 years. Right subtotal maxillectomy with surgical margins of approximately 1.5 cm was performed. The patient remained disease free for 4 years following the ablation surgery. Diagnostic workups, treatment, and therapeutic outcomes were discussed.

CONCLUSION

More cases are needed to further characterize this entity, understand its biological behavior, and justify the treatment protocols. Resection with wide margins of approximately 1.0 to 1.5 cm is proposed, while neck dissection, post-operative radiotherapy, or chemotherapy are deemed unnecessary.

Histopathological diagnosis in pediatric stomatology: A 43-year retrospective study of 1,480 cases from a Brazilian institution

OBJECTIVES

the aim of this study was to analyze the prevalence of histopathological diagnoses in oral biopsied tissues obtained from a Brazilian pediatric population.

METHODS

an analytical, cross-sectional retrospective study was performed with biopsy files of patients ≤14 years of age from a Brazilian oral pathology laboratory over a 43-year period. Data included sex, age, location, and diagnoses. The prevalence was calculated by means of relative frequency. Associations between sex, age groups and diagnoses were verified with Pearson's chi-square test.

RESULTS

from 19,456 oral biopsies, 1480 (7.6%) were obtained from patients aged ≤14 years. Most children were 10-14 years of age (60.1%) and females (55.1%), with an overall M:F of 1:1.2. Children aged 0-9 years and males had a higher frequency of lesions of the oral mucosa, whilst the 10-14 year age group showed a higher frequency of cysts, odontogenic tumors, and salivary gland lesions. The latter was also significantly higher in females. Samples consisted mostly of soft tissue lesions (53%) obtained from the lower lip (30.7%). Intraosseous lesions showed a slight predilection for the mandible (21.2%). Salivary gland lesions (28.8%) was the most common diagnostic category, followed by reactive lesions (18.8%), and cysts (16.1%). Mucocele (33.5%), dentigerous cyst (6.7%), and fibrous hyperplasia (5.9%) were the top three histopathological diagnoses. Malignant lesions affected only 0.9% of this population.

CONCLUSION

our results were similar to other retrospective studies. Due to the low frequency of oral biopsies in children, data on the prevalence of oral pathology in this population might aid in the clinical and histopathologic diagnoses.

Homeobox Genes in Odontogenic Lesions: A Scoping Review

BACKGROUND

Homeobox genes play crucial roles in tooth morphogenesis and development and thus mutations in homeobox genes cause developmental disorders such as odontogenic lesions. The aim of this scoping review is to identify and compile available data from the literatures on the topic of homeobox gene expression in odontogenic lesions.

METHOD

An electronic search to collate all the information on studies on homeobox gene expression in odontogenic lesions was carried out in four databases (PubMed, EBSCO host, Web of Science and Cochrane Library) with selected keywords. All papers which reported expression of homeobox genes in odontogenic lesions were considered.

RESULTS

A total of eleven (11) papers describing expression of homeobox genes in odontogenic lesions were identified. Methods of studies included next generation sequencing, microarray analysis, RT-PCR, Western blotting, in situ hybridization, and immunohistochemistry. The homeobox reported in odontogenic lesions includes LHX8 and DLX3 in odontoma; PITX2, MSX1, MSX2, DLX, DLX2, DLX3, DLX4, DLX5, DLX6, ISL1, OCT4 and HOX C in ameloblastoma; OCT4 in adenomatoid odontogenic tumour; PITX2 and MSX2 in primordial odontogenic tumour; PAX9 and BARX1 in odontogenic keratocyst; PITX2, ZEB1 and MEIS2 in ameloblastic carcinoma while there is absence of DLX2, DLX3 and MSX2 in clear cell odontogenic carcinoma.

CONCLUSIONS

This paper summarized and reviews the possible link between homeobox gene expression in odontogenic lesions. Based on the current available data, there are insufficient evidence to support any definite role of homeobox gene in odontogenic lesions.

Oral giant cell tumor or giant cell granuloma: How to know?

Introduction

The distinction between giant cell tumors and giant cell granulomas is challenging, as both entities have overlapping diagnostic criteria, especially in oral locations. The two entities have similar clinical and radiological presentations, but they differ in their prognoses.

Objective

The main objective of this study was to list the clinical, radiological, histological, and prognostic features of maxillomandibular giant cell tumors and giant cell granulomas cases n order to assess their value as a diagnostic referral factor that may allow the distinction between maxillo-mandibular giant cell granuloma and giant cell tumor.

Study design

Data of maxillomandibular giant cell granulomas and giant cell tumors were assessed through a scoping review and a pre-existing systematic review of literature. We have also realized a bicentric retrospective study.

Results

Various criteria facilitate the differential diagnosis like age, size, locularity and presence of necrosis zone but not the gender. The most discriminating factors was symptomatology (reported in 72% of GCTs while only 15% of GCGs) and the distribution pattern of giant cells in the stroma (homogeneously dispersed in 80% of GCTs versus grouped in clusters in 86.7% of GCGs). Recurrences were most described for giant cell tumors than giant cell granulomas. Malignant transformation and pulmonary metastasis were exclusively reported for giant cell tumors.

Conclusion

As clinical and radiological elements are not sufficient to distinguish between these two entities, immunohistochemistry and molecular genetics can be represent diagnostic biomarkers to distinguish giant cell granulomas and giant cell tumors in oral cavity. We have attempted to define the main criteria for the differentiation of giant cell tumor and giant cell granuloma and propose a decision tree for the management of single maxillomandibular giant cell lesions.

Odontogenic keratocyst in the mandibular condyle base region: A case report

Odontogenic keratocysts (OKCs) often occur in the molars in the mandibular ramus; they often progress asymptomatically and are discovered only after widespread development. Some cases of OKC progress to the mandibular condyle; however, very few cases exist only in the condyle. To the best of our knowledge, in all of the previously reported cases, OKCs occurred in the mandibular ramus, which underwent resection. The present study reports the case of a 31-year-old man in whom an OKC (13x12x6 mm) occurred discretely in the base of the condyle, in which the condylar head was successfully preserved. The tumor was removed under general anesthesia using the approach of shaving the anterior surface of the mandible. The extraction cavity was managed using the packed open technique and with an obturator. Approximately 20 months post-operation, the patient remained recurrence-free. This report presents a rare case of an OKC in the mandibular condyle base region. Resection was performed under general anesthesia and the condylar process was successfully preserved.

Surgical treatment of jaw inflammatory odontogenic cysts in primary teeth: a retrospective analysis

Relevance. Odontogenic cysts in children are the most common bone pathology. The study aimed to conduct a retrospective descriptive analysis of inflammatory odontogenic cysts cases associated with primary teeth in children.Material and methods. The study analysed the medical records of children diagnosed with "radicular cyst associated with a primary tooth" from 2015-2020. We studied the following characteristics, namely, sex, age, location of the process, condition of the teeth in question, surgical treatment techniques and outcome. The data obtained were processed by methods of variational statistics. The Student t-test assessed the significance of differences.Results. The study analysed 60 cases of inflammatory odontogenic cysts in children aged 6 to 13 years. Cysts were more often associated with the primary lower second molars previously treated with the resorcinol-formaldehyde resin therapy. The period from the tooth treatment to the cyst diagnosis was 3 to 5 years. The treatment of cysts applied methods of a gentle and traditional cystotomy. Fifty-one children (85.0%) had follow-up examinations. All children showed bone tissue restoration during the period of 4 to 12 months and spontaneous eruption of permanent teeth in 3-8 months. Only 4 cases (7.8%) required orthodontic correction of permanent teeth position.Conclusion. Primary lower molars, previously treated with resorcinol-formaldehyde resin, are the most common cause of jaw inflammatory odontogenic cysts in children. Low-traumatic surgical methods preserving the follicles of permanent teeth are highly effective (88.2%).

Evaluating histopathological factors of predicting the recurrence rate of odontogenic keratocyst

Background

Odontogenic keratocyst (OKC) is one of the most common jaw cysts with high recurrence rate. Some possible factors affecting recurrence that have not been evaluated in previous studies are examined in this study. This study aimed to predict the recurrence rate of OKC and more viable treatment of OKC.

Materials and Methods

In this descriptive, analytical, and cross-sectional study, 10 recurrent OKCs, which both slides before and after recurrence were accessible, were collected from oral and maxillofacial pathology department's archive. First, they were evaluated based on common histopathologic features. In the second phase, the frequency of these findings in 36 OKCs (24 samples with recurrence and 12 without recurrence after 5 years) was evaluated based on clinical, radiological, and histopathologic features. Data were analyzed by SPSS, Wilcoxon signed-rank test, McNamara, t-test, Chi-square, Mann-Whitney, Fisher's exact test, Cohen's kappa coefficient, and odds ratio (P < 0/05).

Results

According to this study, OKC in women, with multilocular radiolucency and mitosis in basal layer of epithelium as well as diffused inflammation, were statistically associated with probability of recurrence (P = 0.05, 0.035, 0.033, and 0.045, respectively). The corrugated surface, reverse polarity, hypercellularity in parabasal, and satellite cysts can affect the recurrence of OKC with odds ratios = 2.364, 2.364, 1.190, and 1.500, respectively).

Conclusion

Gender (women), multilocular radiolucency, diffused inflammation in stroma, and mitosis in basal layer of epithelial lining, can statically predict the possibility of recurrence rate. In addition, findings regarding the age (in younger patients), corrugated surface, reverse polarity, and sub-basal cleft can be helpful in predicting recurrence.

Transformation of Cemento-Ossifying Fibroma into Osteosarcoma after Radiotherapy and Nine Endoscopic Surgeries

Cemento-ossifying fibromas (COFs) are benign fibro-osseous tumors usually found in the mandible and maxilla that can show malignancy in rare situations. COFs usually grow slowly and asymptomatically until they produce local bulges, pain, headaches, and visual impairment, and have a Ki-67 index within 3%, even in aggressive and recurrent cases. Surgical resection can usually provide a satisfactory prognosis. However, no cases of COF transforming into osteosarcoma have been reported. We present a case of COF involving a 58-year-old woman whose initial symptom was hearing loss in the right ear accompanied by tinnitus. Enhanced magnetic resonance imaging revealed a 3.1 cm x 3.2 cm mass centered on the right pterygoid process of the sphenoid bone. Postoperative pathology revealed a COF with a high Ki-67 index (8%-10%). Over the next two years, the tumor relapsed repeatedly. The patient underwent nine endoscopic surgeries and radiotherapy. The sixth postoperative biopsy showed that the COF had transformed into an osteosarcoma. The patient subsequently experienced respiratory and cardiac arrests and was receiving treatment in the intensive care unit with a poor prognosis at the time of writing this manuscript. Thus, a high Ki-67 index may be a risk factor for malignant transformation for COFs.

Ameloblastomatous calcifying cystic odontogenic tumour involving the mandibular anterior region: An unusual case report

Ameloblastomatous calcifying odontogenic cyst (COC) is a very rare histopathological variant of COC, which is an odontogenic cyst of the jaw. The term "calcifying odontogenic cyst" is not covered in the World Health Organisation (WHO) Classification of Tumors 2005 and was re-named as calcifying cystic odontogenic tumour (CCOT). There are only a few reports containing details on CCOT being associated with ameloblastoma. This variant has been classified as ameloblastomatous CCOT (type 3) as per the WHO 2005 classification. In this article, we reported an exceptional case of ameloblastomatous CCOT in a 15-year-old boy involving the mandibular anterior region, which is a rare combination for age and site of the lesion, along with an impacted tooth which is again an uncommon association.

MR appearance of a rare ameloblastic fibroma with formation of dental hard tissues with histopathologic correlation: a case report

An ameloblastic fibroma with formation of dental hard tissues, which the classical name is ameloblastic fibro-odontoma (AFO), is a rare type of mixed odontogenic tumor. An 8-year-old boy was diagnosed with AFO, with an inhomogeneous high signal within the lesion shown by T2-weighted magnetic resonance imaging (MRI). Computed tomography (CT) imaging revealed a unilocular low CT value area of 24 × 19 × 26 mm with buccolingual bony expansion and cortical bone thinning on the left side of the mandible including the crown of the mandibular left second molar. In addition, multiple calcified bodies were detected within the lesion, one of which had a CT value of approximately 2200 HU, equivalent to that of enamel. MRI indicated the lesion to be sized 24 × 19 × 25 mm along with buccolingual bony expansion in the left side of the mandible. Additionally, the lesion showed an internal inhomogeneous high signal, while a portion had an especially high signal in T2-weighted images. That particularly high signal area coincided with the nodular growth area of mucus-rich mesenchymal components without the epithelial component in histopathology findings. The particularly high signal revealed by T2-weighted imaging could be attributed to the mucus-rich component. MRI was found useful for revealing differences in the internal histopathological properties of an AFO in our patient.

Ossifying Fibroma in the Maxilla and Mandible: A Case Report With a Brief Literature Review

Fibro-osseous lesions in the jaw bones include fibrous dysplasia, ossifying fibroma (OF), cemento-ossifying fibroma, florid osseous dysplasia, and focal osseous dysplasia. OF is the most common fibro-osseous tumor that presents as a slow-growing well-encapsulated benign neoplasm composed of varying amounts of bone or cement-like tissue in a fibrous stroma well-demarcated from the adjacent normal bone. OF is most common in the jaw bones, with a predilection for the mandible. OF usually occur as solitary lesions and rarely as multiple lesions in a patient. We present clinical and radiologic features, histopathology, and surgical management of a rare case with large synchronous OFs in the mandible and maxilla and a brief review of the literature.

Jaw Cysts: A Retrospective Study in a Turkish Subpopulation

Objectives: Cysts seen in the jaws may be odontogenic or non-odontogenic, depending on the tissue of origin. Although there are different methods to diagnose these lesions, histopathological examination of tissue biopsy of the lesion is accepted as the 'gold standard' in cases where the diagnosis is insufficient. Although there are different methods to diagnose these lesions, histopathological examination of tissue biopsy of the lesion is accepted as the 'gold standard' in cases where the diagnosis is insufficient. Materials and Methods: Pathology results of 436 patients who applied to Zonguldak Bülent Ecevit University Faculty of Dentistry, Oral and Maxillofacial Radiology Clinic between 2016-2021 for any reason and underwent biopsy were retrospectively scanned using digital archives. While classifying the cyst, the criteria published by the World Health Organization (WHO) in 2017 were taken into account. Obtained results were recorded for statistical analysis. SPSS 22.0 Software Package Program (SPSS 22.0 Software Package Program, Inc. Chicago, IL, USA) was used as statistical software in the study. Results: Of the 436 patients included in the study, 250 (57.3%) were male and 186 (42.7%) were female. The ages of the patients ranged between 7 and 82 years, and the mean age of the patients was 35.5±15.8. As a result of the findings, it was determined that the most common cysts were radicular cysts (53.7%). Radicular cysts were most commonly located in the posterior mandible and anterior maxilla anatomically. Conclusions: In addition to clinical and radiological examination, histopathological examination of biopsy samples taken from tissues is of great importance in the correct diagnosis and treatment planning of jaw cysts.

Factors Influencing the Aggressive Behavior of Odontogenic Keratocyst: A Narrative Review

During odontogenesis, the dental lamina disintegrates, leaving behind the remnants. Odontogenic pathologies such as cysts and tumors can arise from these remnants. The odontogenic keratocyte (OKC) arises from dental lamina remnants. Among the cysts, the odontogenic keratocyst is the most controversial. There is convincing evidence that inflammation plays a significant role in the pathogenesis and expansion of OKCs. Several factors mediate the proliferative capacity of the epithelial lining. The presence of mast cells close to the epithelial lining, cystic pressure build-up by vascular endothelial growth factors (VEGFs), and other cytokines contribute to the cystic expansion. Fibroblast activation by inflammation in the connective tissue stroma and changes in the epithelial lining are responsible for the aggressive nature of OKC. The use of molecular methodologies gives more profound insights into the factors influencing the progression of the lesion and helps develop newer treatment modalities for OKC. This review describes the characteristics that determine the aggressive behavior of this unique cyst.

Recurrent Ameloblastoma: Long Term Outcomes with Free Fibular Bone Graft

Ameloblastoma is a locally aggressive benign neoplasm of jaw that has high propensity to recur. Pathological subtype and intent of surgical excision during primary surgery are two factors that are known to affect the prognosis in these cases. Nevertheless, there are hardly any studies which have studied recurrent ameloblastoma cases. Apart from sharing a tertiary care cancer center's experience in managing a series of recurrent ameloblastoma cases, we discuss some of the recent literature related to pathophysiology and principles related to their surgical management. Retrospective chart review of all those recurrent ameloblastoma cases which were operated between October 2013 and January 2016 and were subsequently followed up for minimum of 3 years. Total of 9 recurrent ameloblastoma cases were operated in the study period. All our patients had less-radical or non-curative intent surgical treatment in the past, and current treatment consisted wide excision of the involved segment of mandible with free fibular reconstruction. Among the 6 patients who were followed up for more than 3 years, none developed recurrence at 56.5 months of mean follow up duration. Almost all these patients had optimal results with good quality of life in terms of oral speech intellectuality and cosmetic perception of self. Complete excision of the involved segment of bone with reconstruction using the composite free fibular graft can provide optimal functional outcomes and can significantly lessen the chances of further recurrences.

Intraosseous jaw lesions: A 25-year experience

Context

Jaw bones can be afflicted by to a diverse group of lesions ranging from developmental, reactive/inflammatory, cystic lesions to tumors and tumor-like lesions.

Objectives

The objective of this study is to determine the relative frequency, demographic and pathologic profiles of patients with intraosseous jaw lesions from Thailand.

Subjects and Methods

Biopsy records from 1995 to 2019 were reviewed. Age, gender and location of the lesions were collected from the biopsy records. Data were analyzed by appropriate statistics using the IBM SPSS software version 22.0.

Results

From 23,344 accessioned cases, 7382 cases (31.62%) were encountered within the jaw bones. Age of the participants ranged from 1 to 96 years with the mean ± standard deviation = 36.05 ± 17.80 years. Pediatric participants (aged ≤16 years) comprised 13.80% of all the participants, whereas the geriatric ones (aged ≥65 years) accounted for 7.55%. The male-to-female ratio was 0.89:1. The majority of lesions were observed in the mandible. The most prevalent intra-osseous jaw lesion was radicular cyst followed by dentigerous cyst and ameloblastoma. The most common malignant tumor was osteosarcoma followed by ameloblastic carcinoma and lymphoma. Among the pediatric participants, dentigerous cyst was the most prevalent jaw lesion, while that in the geriatric participants was radicular cyst.

Conclusions

This is the largest study on intra-osseous jaw lesions encompassing several pathological entities ever conducted from Thailand. It thus provides an invaluable database for clinicians to formulate a differential diagnosis as well as for the pathologists to render the final diagnosis. The results of this study are in accordance with previous studies in general.

Clinical, Diagnostic and Histological Findings Involving Cheek Teeth Hypercementosis in Nine Horses

Hypercementosis is infrequently reported to affect the cheek teeth of horses and presents as mineral deposits either attached (peripheral) or solitary ovoid (nodular) structures in the tooth bearing region. There is overlap between radiological and histological appearance of hypercementosis, cementoma, and equine odontoclastic tooth resorption and hypercementosis (EOTRH). The clinical presentation, imaging features, surgical management, and histological findings of nine horses that presented for dental lesions and associated hypercementosis of cheek teeth are reported. Horses were 4-15 years old and presented for either nasal discharge or facial swelling. Peripheral and nodular mineral structures were identified using radiographs or computed tomography in six and three horses, respectively. Eight of nine cases involved maxillary cheek teeth. Of six cases with peripheral hypercementosis, three had enlargement of the apical cross-sectional area that was greater than the coronal cross-sectional area thus preventing extraction along the normal eruption pathway and necessitating sectioning (two cases) and repulsion. Nodular hypercementosis lesions were extracted in three of the four cases. Post-extraction complications occurred in five cases; four cases required additional procedures. All horses returned to their intended use, ie riding or pasture. Histology of extracted dental and proliferative mineral material revealed hypercementosis characterized by large sheets of eosinophilic matrix with lacunae (usually empty; presumed artifact) and frequent, irregular, basophilic cement lines. All cases had evidence of chronic inflammation, such as caries, chronic fractures and/or pulpitis. The findings of this case series share many features with previous published descriptions of cementoma and with histological findings of hypercementosis lesions of EOTRH. Further investigation into differentiation of these entities is warranted.

Keratoameloblastoma: A Report of Seven New Cases and Review of Literature

BACKGROUND

Keratoameloblastoma (KA) is an uncommon and controversial variant of ameloblastoma exhibiting central keratinisation. Due to their rarity, there is limited information in the literature on their clinical, radiologic and histologic features. This study adds seven additional cases of KA to the literature, and reviews the current published literature on this rare entity.

METHODS

KAs were retrospectively reviewed over a 20-year period from three Oral and Maxillofacial Pathology Laboratories. Included cases were examined and the diagnosis confirmed under conventional microscopy. Immunohistochemistry with the use of a monoclonal antibody against calretinin was performed on included cases. The clinical, radiologic and histologic features of the seven new cases of KA were analysed and compared to existing cases in the literature.

RESULTS

KAs presented at a mean age of 40 years with a nearly equal gender distribution and a mandibular predilection (65%). The majority (92%) of cases presented with localised swelling with associated pain in 32% of cases. Mixed density or internal calcifications were noted in 40% of cases. All tumours presented with bony expansion, with cortical destruction noted in 62% of cases. Histologically, all tumours consisted of solid and cystic follicles with surface parakeratinisation and lamellated accumulations of central keratin. In areas the cystic follicles had an epithelial lining suggestive of an OKC. There were focal luminal areas of loosely arranged polygonal cells reminiscent of the stellate reticulum. The basal cells consisted of columnar cells with evidence of palisading and prominent subnuclear vacuolisation. Of the cases treated via tumour resection, 27% presented with tumour recurrence.

CONCLUSION

This case series reports seven additional cases of KA, taking the total to 26 reported cases. The identification of subtle histologic features, including focal stellate reticulum-like central areas, subnuclear vacuolisation and lamellated-type central keratinisation, are key in diagnosing KA. The radiologic features will often indicate signs of aggressiveness such as cortical destruction, differentiating KA from OKC. All cases were completely negative for calretinin IHC, limiting its use in distinguishing KA from OKC. Further large series are needed to expand the current understanding of this rare variant of ameloblastoma.

Expression of Matrix Metalloproteinases 7 and 9, Desmin, Alpha-Smooth Muscle Actin and Caldesmon, in Odontogenic Keratocyst Associated with NBCCS, Recurrent and Sporadic Keratocysts

Nevoid basal cell carcinoma syndrome (NBCCS) associated odontogenic keratocysts (OKCs) show more aggressive behavior and it has a higher frequency of relapse than non-syndromic OKCs. Stromal myofibroblasts (MFs), characterized by α-smooth muscle actin (αSMA), desmin and caldesmon expression, and metalloproteinases (MMPs) have an essential role in the remodeling of the extracellular matrix (ECM). The aim of the study is to analyze the immunohistochemical expression of MMP-7, MMP-9, αSMA and other new markers in the study of OKCs MFs such as desmin and caldesmon in NBCCS-associated OKCs compared to recurrent and sporadic keratocysts. Fourty 40 patients (23 M and 17 F) underwent surgery to remove the OKCs. The histological sections in paraffin were incubated with markers antibodies and a semi-quantitative score was used to evaluate the immunoreactivity. Densitometric analysis showed a very significantly increased expression of αSMA, caldesmon, MMP-7 and MMP-9 in NBCCS-OKCs compared to non-syndromic OKCs (p < 0.001). However, desmin showed a not significant increased expression in non-syndromic OKC compared to NBCCS-OKCs specimens in which desmin was slightly or not at all expressed. NBCSS-OKCs showed a greater distribution of MFs compared to the other OKCs subtypes. Further studies will be needed to evaluate whether the different expressions of these markers can be correlated to a different clinical behavior.

Compound odontoma associated with a calcifying odontogenic cyst. Case report and systematic review

The objectives of the present study were to comprehensively evaluate all the published cases on compound odontoma associated with calcifying odontogenic cyst (COaCOC) in the English literature and to describe the clinical, imaging and therapeutic variables for this condition. In August 2020, an electronic search of the PubMed / MEDLINE, Web of Science, ScienceDirect, Springer, and Scopus databases was carried out. The eligibility criteria included publications with enough information to confirm the diagnosis. Furthermore, we present a clinical case of a 16-year-old male patient with OCCaC, who was treated with enucleation, obtaining favorable and functional results. A total of 32 cases reported in the literature that met the inclusion and exclusion criteria, including ours, were analyzed and discussed. The mayority of the patients were women (n = 17) with an average age of 14.4 years, the maxilla was the most affected bone (n = 22) and the maxillary anterior region was the area with the highest number of cases (n = 18), the main clinical presentations were the volume increase (n = 14) and asymptomatic (n = 14). The choice treatment was enucleation (n = 26) and, in most cases, no recurrence was reported (n = 20). This study allows to update the characteristics of the OCCaC, giving an effective vision of how to treat this rare pathological association made up of two conditions that are completely different from each other.

Compound Odontoma Associated with Dentigerous Cyst Incidentally Detected in an Adult Patient: Tomography and Histological Features

Odontoma is the most common benign odontogenic tumor of epithelial and mesenchymal origin. The standard treatment involves a conservative approach. While this procedure is generally well accepted and tolerated, some difficulties may arise in case of odontomas associated with cystic lesions. In general, the expansive nature of cystic lesions requires their surgical excision, different from isolated nonsymptomatic odontomas that can be monitored radiographically. However, to the best of our knowledge, there is scarce evidence currently available reporting on the presence of odontoma-associated cystic lesions in the oral cavity. Therefore, the present case report is aimed at describing the diagnostic clinical, radiological, and histological features together with the surgical management of a dentigerous cyst associated with a compound odontoma. Following surgical removal of the lesion, no recurrence was observed after 12 months of follow-up.

Immunoexpression of CXCL12 and CXCR4 in sporadic and Gorlin-Goltz syndrome-related odontogenic keratocysts

Background

Differences in the pathogenesis and biological behavior of sporadic and Gorlin-Goltz syndrome-related odontogenic keratocysts (OKCs) have been reported, but the underlying mechanisms are not fully elucidated. Chemokine CXCL12 and its main receptor CXCR4 regulate important events in the pathogenesis of several lesions.

Material and Methods

This study evaluated the immunoexpression of CXCL12 and CXCR4 in sporadic and syndromic OKCs. Twenty-two sporadic OKCs and 22 syndromic OKCs were subjected to immunohistochemistry. The percentages of cytoplasmic (CXCL12 and CXCR4) and nuclear (CXCR4) staining in epithelial and fibrous capsule cells were determined. The results were analyzed statistically using the nonparametric Mann-Whitney test and Spearman correlation test (p<0.05).

Results

Higher cytoplasmic expression of CXCL12 was observed in the epithelial lining and fibrous capsule of sporadic OKCs compared to syndromic OKCs (p<0.001). No statistically significant differences in the cytoplasmic expression of CXCR4 were observed between syndromic OKCs and sporadic OKCs (p>0.05). Compared to syndromic OKCs, sporadic OKCs exhibited higher nuclear expression of CXCR4 in the epithelial lining and lower immunoexpression in the fibrous capsule (p<0.05). In the epithelial lining of syndromic OKCs, positive correlation was observed between cytoplasmic and nuclear expressions of CXCR4 (p=0.003). In the fibrous capsule of syndromic OKCs and sporadic OKCs, cytoplasmic and nuclear expressions of CXCR4 were positively correlated (p<0.001).

Conclusions

The results suggest a potential participation of CXCL12 and CXCR4 in the development of OKCs. The heterogeneous expression of these proteins in syndromic and sporadic OKCs may reflect differences in their pathogenesis and biological behavior. Key words:Odontogenic keratocyst, CXCL12, CXCR4, Immunohistochemistry.

Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts

BACKGROUND

The odontogenic jaw cyst is a cavity containing liquid, semifluid or gaseous components, with the development of the disease. In recent years, with the rapid development of oral materials and the transformation of treatment of jaw cysts, more options are available for treatment of postoperative bone defect of jaw cysts. Guided bone regeneration (GBR) places biomaterials in the bone defect, and then uses biofilm to separate the proliferative soft tissue and the slow-growing bone tissue to maintain the space for bone regeneration, which is widely used in the field of implantology.

AIM

To observe the clinical effect of GBR in repairing bone defect after enucleation of small and medium-sized odontogenic jaw cysts.

METHODS

From June 2018 to September 2020, 13 patients (7 male, 6 female) with odontogenic jaw cysts were treated in the Department of Oral Surgery, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine. Adults without hypertension, heart disease, diabetes or other systemic diseases were selected. The diagnosis was based on the final pathological results: 11 cases were diagnosed as apical cysts, one as primordial cyst, and one as dentigerous cyst. The lesions were located in the maxilla in seven cases, and in the mandible in six cases. All cases were treated with the same method of enucleation combined with GBR.

RESULTS

Three to four months after the operation, the boundary between the implant site and the surrounding normal stroma was not obvious in patients with small-sized odontogenic jaw cysts. The patients with tooth defects were treated with implant after 6 mo. For the patients with medium-sized odontogenic jaw cysts, the density of the center of the implant area was close to the normal mass at 6 mo after surgery, and there was a clear boundary between the periphery of the implant area and the normal mass. The boundary between the periphery of the implant area and the normal mass was blurred at 8-9 mo after surgery. Patients with tooth defects were treated with implants at > 6 mo after the operation.

CONCLUSION

Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts can shorten the time of osteogenesis, increase the amount of new bone formation, reduce complications, and improve quality of life.

BMPR1α promotes osteolytic lesion of oral squamous cell carcinoma by SHH‐dependent osteoclastogenesis

Oral squamous cell carcinoma (OSCC) is an aggressive tumor that usually invades the maxilla or mandible. The extent and pattern of mandibular bone invasion caused by OSCC are the most important factors determining the treatment plan and patients' prognosis. Yet, the process of mandibular invasion is not fully understood. The following study explores the molecular mechanism that regulates the mandibular invasion of OSCC by focusing on bone morphogenetic protein receptor 1α (BMPR1α) and Sonic hedgehog (SHH) signals. We found that BMPR1α was positively correlated to bone defect of OSCC patients. Mechanistically, BMPR1α signaling regulated the differentiation and resorption activity of osteoclasts through the interaction of OSCC cells and osteoclast progenitors, and this process was mediated by SHH secreted by tumor cells. The inhibition of SHH protected bone from tumor‐induced osteolytic activity. These results provide a potential new treatment strategy for controlling OSCC from invading the jawbones.