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Targeted therapy has the potential to be used in the neoadjuvant setting for odontogenic tumors, reducing the morbidities associated with major surgery. In this regard, the aim of this study was to summarize the current evidence on the different forms of targeted therapy, effectiveness, and drawbacks of this course of treatment. Four databases were searched electronically without regard to publication date or language. Grey literature searches and manual searches were also undertaken. Publications with sufficient clinical data on targeted therapy for odontogenic tumors were required to meet the criteria for eligibility. The analysis of the data was descriptive. A total of 15 papers comprising 17 cases (15 ameloblastomas and 2 ameloblastic carcinomas) were included. Numerous mutations were found, with BRAF V600E being most common. Dabrafenib was the most utilized drug in targeted therapy. Except for one case, the treatment reduced the size of the lesion (16/17 cases), showing promise. Most of the adverse events recorded were mild, such as skin issues, voice changes, abnormal hair texture, dry eyes, and systemic symptoms (e.g., fatigue, joint pain, and nausea). It is possible to reach the conclusion that targeted therapy for ameloblastoma and ameloblastic carcinoma may be a useful treatment strategy, based on the findings of the included studies. [ABSTRACT FROM AUTHOR]

The article focuses on the detection of the BRAF V600E mutation in cell-free DNA (cfDNA) extracted from fluid aspirates of conventional ameloblastomas. It explores the potential of using liquid biopsy as a minimally invasive alternative to traditional tissue biopsies for diagnosing this mutation, which is prevalent in ameloblastomas and could significantly impact clinical management and treatment strategies.

ABSTRACT Background Methods Results Conclusion Ameloblastoma is a locally destructive benign odontogenic tumor. While the neoplastic cells of conventional ameloblastoma can infiltrate the connective tissue and bone, in unicystic ameloblastoma the epithelium is encapsulated. The mechanisms driving ameloblastoma's bone resorption remains unclear.RNA sequencing (RNA‐seq) was performed in a discovery cohort of conventional ameloblastoma, and pathway enrichment analysis was carried out. mRNA levels of MMP13, a gene associated with bone resorption, were assessed using RT‐qPCR in a larger cohort of conventional ameloblastoma and in unicystic ameloblastoma. Zymogram gels and the immunoexpression profile of collagenase 3 (encoded by MMP13 gene) were evaluated as well.Enriched pathways related to bone mineralization and upregulation of MMP13 were observed in ameloblastomas. Collagenolytic activity of collagenase 3 was detected in the tumor lysates. Collagenase 3 immunopositivity was observed in ameloblastomatous epithelium infiltrating the fibrous capsule of unicystic ameloblastoma. At the tumor–bone interface, collagenase 3 expression was detected in stromal cells, osteoblasts, and osteocytes.The results indicate a potential involvement of MMP13 in ameloblastoma‐related bone resorption and progression. [ABSTRACT FROM AUTHOR]

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Adenoid ameloblastoma is a newly recognized epithelial odontogenic tumor. Herein, we present the case of a 24-year-old male patient who exhibited swelling in the anterior region and right hemi-mandible. Computed tomography demonstrated the presence of a hypodense osteolytic lesion associated with an impacted tooth. Based on the clinical hypotheses of the dentigerous cyst, odontogenic keratocyst, and ameloblastoma, an incisional biopsy was performed, and the diagnosis of ameloblastoma was rendered. A surgical resection of the tumor was performed. Histopathological examination of the specimen revealed typical areas of ameloblastoma associated with ductiform structures and cell proliferation in a solid storiform pattern, features resembling those found in adenomatoid odontogenic tumor. Based on these findings, the diagnosis of adenoid ameloblastoma was rendered. The accurate diagnosis of this locally infiltrative tumor is essential due to its similarity to other odontogenic neoplasms. [ABSTRACT FROM AUTHOR]

Unicystic ameloblastoma (UAM) of the jaw can be effectively reduced in volume through decompression, which promotes bone regeneration and restores jaw symmetry. This study quantitatively evaluated changes in mandible volume and symmetry following decompression of mandibular UAM. This study included 17 patients who underwent surgical decompression followed by second-stage curettage for mandibular UAM. Preoperative and postoperative three-dimensional computed tomography (CT) images were collected. Bone volume and the area of cortical perforation were measured to assess bone growth during decompression. Mandibular volumetric symmetry was analyzed by calculating the volumetric ratio of the two sides of the mandible. Twelve pairs of landmarks were identified on the surface of the lesion regions, and their coordinates were used to calculate the mean asymmetry index (AI) of the mandible. Paired t-tests and the Mann–Whitney U test were used for statistical analysis, with p < 0.05 considered indicative of statistical significance. The mean duration of decompression was 9.41 ± 3.28 months. The mean bone volume increased by 8.07 ± 2.41%, and cortical perforation recovery was 71.97 ± 14.99%. The volumetric symmetry of the mandible improved significantly (p < 0.05), and a statistically significant decrease in AI was observed (p < 0.05). In conclusion, UAM decompression enhances bone growth and symmetry recovery of the mandible. The present evaluation technique is clinically useful for quantitatively assessing mandibular asymmetry. [ABSTRACT FROM AUTHOR]

Objective: Although benign, ameloblastoma is a locally aggressive lesion in some patients and the development of additional treatments is needed. Verteporfin (VP) is a photosensitizer exhibiting considerable photocytotoxicity in various tumor cells. We aimed to investigate the effects of verteporfin photodynamic therapy (VP PDT) on ameloblastoma. Methods: Eighteen patients who underwent surgery for ameloblastoma were randomly selected. We performed an immunohistochemical assessment to investigate the expression of low‐density lipoprotein receptor (LDLR) and Yes‐associated protein (YAP), targets of VP, in human ameloblastoma tissues and cultured human ameloblastoma cell line (HAM1). The effect of VP PDT on cell proliferation and apoptosis in HAM1 was analyzed. Results: The expression of LDLR and YAP were detected in human ameloblastoma tissues and HAM1. LDLR expression was significantly higher in patients who had previously undergone surgery than in patients who were receiving it for the first time. The cytotoxic effect of the combination of low‐concentration VP administration and laser irradiation was comparable to high‐concentration VP administration with and without laser irradiation. The addition of laser irradiation to VP administration significantly accelerated apoptotic bleb formation compared with VP administration alone. Conclusion: VP PDT has the potential to become an additional treatment for large‐sized ameloblastoma. [ABSTRACT FROM AUTHOR]

Background: BRD4, belonging to the bromodomain extra‐terminal (BET) protein family, plays a unique role in tumor progression. However, the potential impact of BRD4 in ameloblastoma (AM) remains largely unknown. Herein, we aimed to assess the expression and functional role of BRD4 in AM. Methods: The expression level of BRD4 was assessed by immunohistochemistry. The proliferation, migration, invasion, and tumorigenic abilities of AM cells were assessed by a series of assays. To explore the molecular expression profile of BRD4‐depleted AM cells, RNA sequencing (RNA‐seq) was performed. Bioinformatic analysis was performed on AM expression matrices obtained from the Gene Expression Omnibus (GEO). The therapeutic efficacy of BET‐inhibitors (BETi) was assessed with AM patient‐derived organoids. Results: Upregulation of BRD4 was observed in conventional AMs, recurrent AMs, and ameloblastic carcinomas. Depletion of BRD4 inhibited proliferation, invasion, migration, and tumorigenesis in AM. Administration of BETi attenuated the aggressiveness of AM and the growth of AM patient‐derived organoids. Bioinformatic analysis indicated that BRD4 may promote AM progression by regulating the Wnt pathway and stemness‐associated pathways. Conclusion: BRD4 increases the aggressiveness and promotes the recurrence of ameloblastoma by regulating the Wnt pathway and stemness‐associated pathways. These findings highlight BRD4 as a promising therapeutic target in AM management. [ABSTRACT FROM AUTHOR]

Objective: This Bayesian network meta‐analysis was performed to analyze the associations between clinicopathological characteristics and BRAF mutations in ameloblastoma (AM) patients and to evaluate the diagnostic accuracy. Materials and Methods: Four electronic databases were searched from 2010 to 2024. The search terms used were specific to BRAF and AM. Observational studies or randomized controlled trials were considered eligible. The incidence of BRAF mutation and corresponding clinicopathological features in AM patients were subjected to Bayesian network analyses and diagnostic accuracy evaluation. Results: A total of 937 AM patients from 20 studies were included. The pooled prevalence of BRAF mutations in AM patients was 72%. According to the Bayesian network analysis, BRAF mutations are more likely to occur in younger (odds ratio [OR], 2.3; credible interval [CrI]: 1.2–4.5), mandible site (OR, 3.6; 95% CrI: 2.7–5.2), and unicystic (OR, 1.6; 95% CrI: 1.1–2.4) AM patients. Similarly, higher diagnostic accuracy was found in the younger, mandible, and unicystic AM groups. Conclusions: The incidence, risk, and diagnostic accuracy of BRAF mutation in AM were greater in younger patients, those with mandible involvement, and those with unicystic AM than in patients with other clinicopathological features. In addition, there was a strong concordance in the diagnostic accuracy between molecular tests and immunohistochemical analysis. [ABSTRACT FROM AUTHOR]

Minichromosome maintenance (MCM) protein 2 is critical for the beginning of DNA replication and is a notable marker for proliferating cells. The prognosis and management of ameloblastoma are based on histology and other factors. However, immunohistologic markers capable of detecting recurrence-prone ameloblastoma with a poor prognosis have not been adequately investigated. This study aimed to identify the association between MCM2 overexpression and recurrence prognosis and risk stratification. Thirty-two patients who had been diagnosed with ameloblastoma at our department between January 1982 and December 2019 were included in this study. Thirty-two (fifteen follicular, ten plexiform, five unicystic, two desmoplastic) subtype cases were analyzed for immunohistochemical expressions of MCM2 and Ki-67. Disease-free survival (DFS) analysis revealed that patients with MCM2high/Ki-67high ameloblastoma had a significantly shorter median survival time (63 vs. 360 months) and lower DFS survival rate (50.0% vs. 90.0%) than those with MCM2low/Ki-67low (p = 0.003). Multivariate analysis revealed that a location (maxillary primary ameloblastoma) and MCM2high/Ki-67high were independent risk factors for DFS. Our results identified MCM2high/Ki-67high ameloblastoma as a subgroup with poor recurrent prognosis and DFS. Ameloblastoma should be assessed using immunohistochemical staining. Our study revealed that tumors with a worse recurrent prognosis require appropriate clinical surveillance. [ABSTRACT FROM AUTHOR]

The current study aims at investigating gap junctions which allow cells to connect with one another. Such process is essential for cell differentiation and the preservation of diverse cell functions. It is noticeable that connexin 43 (Cnx43) was differentially expressed in ameloblasts and odontoblasts in the processes of odontogenesis. Moreover, in carcinoma in situ (CIS) and oral squamous cell carcinoma (SCC), Cnx43 expression apparently thought to be a defining feature of the neoplastic state of squamous epithelial cells. Aim : Therefore, the study has postulated that Cnx43 may be involved in the pathophysiology of ameloblastoma and certain odontogenic cysts whose epithelial constituents exhibit squamous cells. In order to prove the foregoing hypothesis, the study explored the immunohistochemical profiles of Cnx43 in ameloblastoma as well as some odontogenic cysts to assess Cnx43 trafficking and its relation with characteristic tissue architectures of odontogenic lesions. Results : The study has concluded that Cnx43 was down regulated significantly in follicular ameloblastoma with obvious ameloblasts-like cell components as well as in odontogenic keratocyst with palisaded basal cells. Additionally, other patterns of ameloblastoma (plexiform and desmoplastic) and different types of odontogenic cysts manifest heavy trafficking for Cnx43. Conclusion : Finally, altered Cnx43 expression between various patterns of ameloblastoma and odontogenic cysts might be related to their pathogenesis and is responsible for their morphological diversity. [ABSTRACT FROM AUTHOR]

Xu Huang,&ast; Feihan Gu,&ast; Mingyu Zhao, Wenkai Huang, Wenjia Han, Ran Chen, Yuanyin Wang College & Hospital of Stomatology, Anhui Medical University, Key Laboratory of Oral Diseases Research of Anhui Province, Hefei, 230032, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Ran Chen; Yuanyin Wang, College & Hospital of Stomatology, Anhui Medical University, Key Laboratory. of Oral Diseases Research of Anhui Province, No. 81, Meishan Road, Shushan District, Hefei City, 230032, People’s Republic of China, Email ahmuchenran@163.com; wyy1970548@sohu.comAbstract: Ameloblastoma (AB) is a common odontogenic tumor that develops in the mouth. Despite its benign nature, AB exhibits significant invasiveness leading to tumor metastasis and high postoperative recurrence rates. Studies have shown a relationship between the occurrence and development of various tumors and non-coding RNA (ncRNA). NcRNA, transcribed from the genomes of mammals and other complex organisms, are often products of alternative splicing and processing into smaller products. MicroRNA (miRNA), circular RNA (circRNA), and long non-coding RNA (lncRNA) are the main types of ncRNA. NcRNA play increasingly significant roles in the pathogenesis of human cancers, regulating their occurrence and progression as oncogenes or tumor suppressors. They are involved in tumor development and progression through alternative splicing of pre-mRNA, transcriptional regulation, mRNA stability, protein translation, and chromatin remodeling and modification. The importance of ncRNA in AB has received significant attention in recent years. However, the biological functions and mechanisms of ncRNA in AB remain largely unknown. In this review, we not only explore the functions and roles of ncRNA in AB, but also describe and envision their potential functional roles as biomarkers in AB diagnosis. In particular, we highlight the potential of miR-29a as a molecular marker for diagnosis and therapy. As promising novel therapeutic targets, the biological functions of ncRNA need further study, which is indispensable.Keywords: ameloblastoma, miRNA, biomarker, therapy

Abstract Unicystic ameloblastoma (UAM) of the jaw can be effectively reduced in volume through decompression, which promotes bone regeneration and restores jaw symmetry. This study quantitatively evaluated changes in mandible volume and symmetry following decompression of mandibular UAM. This study included 17 patients who underwent surgical decompression followed by second-stage curettage for mandibular UAM. Preoperative and postoperative three-dimensional computed tomography (CT) images were collected. Bone volume and the area of cortical perforation were measured to assess bone growth during decompression. Mandibular volumetric symmetry was analyzed by calculating the volumetric ratio of the two sides of the mandible. Twelve pairs of landmarks were identified on the surface of the lesion regions, and their coordinates were used to calculate the mean asymmetry index (AI) of the mandible. Paired t-tests and the Mann–Whitney U test were used for statistical analysis, with p

Background: The current study aims at investigating gap junctions which allow cells to connect with one another. Such process is essential for cell differentiation and the preservation of diverse cell functions. It is noticeable that connexin 43 (Cnx43) was differentially expressed in ameloblasts and odontoblasts in the processes of odontogenesis. Moreover, in carcinoma in situ (CIS) and oral squamous cell carcinoma (SCC), Cnx43 expression apparently thought to be a defining feature of the neoplastic state of squamous epithelial cells. Aim: Therefore, the study has postulated that Cnx43 may be involved in the pathophysiology of ameloblastoma and certain odontogenic cysts whose epithelial constituents exhibit squamous cells. Materials and methods: In order to prove the foregoing hypothesis, the study explored the immunohistochemical profiles of Cnx43 in ameloblastoma as well as some odontogenic cysts to assess Cnx43 trafficking and its relation with characteristic tissue architectures of odontogenic lesions. Results: The study has concluded that Cnx43 was down regulated significantly in follicular ameloblastoma with obvious ameloblasts-like cell components as well as in odontogenic keratocyst with palisaded basal cells. Additionally, other patterns of ameloblastoma (plexiform and desmoplastic) and different types of odontogenic cysts manifest heavy trafficking for Cnx43. Conclusion: Finally, altered Cnx43 expression between various patterns of ameloblastoma and odontogenic cysts might be related to their pathogenesis and is responsible for their morphological diversity.

Background: Ameloblastoma, a common benign tumor found in the jaw bone, necessitates accurate localization and segmentation for effective diagnosis and treatment. However, the traditional manual segmentation method is plagued with inefficiencies and drawbacks. Hence, the implementation of an AI-based automatic segmentation approach is crucial to enhance clinical diagnosis and treatment procedures. Methods: We collected CT images from 79 patients diagnosed with ameloblastoma and employed a deep learning neural network model for training and testing purposes. Specifically, we utilized the Mask R-CNN neural network structure and implemented image preprocessing and enhancement techniques. During the testing phase, cross-validation methods were employed for evaluation, and the experimental results were verified using an external validation set. Finally, we obtained an additional dataset comprising 200 CT images of ameloblastoma from a different dental center to evaluate the model's generalization performance. Results: During extensive testing and evaluation, our model successfully demonstrated the capability to automatically segment ameloblastoma. The DICE index achieved an impressive value of 0.874. Moreover, when the IoU threshold ranged from 0.5 to 0.95, the model's AP was 0.741. For a specific IoU threshold of 0.5, the model achieved an AP of 0.914, and for another IoU threshold of 0.75, the AP was 0.826. Our validation using external data confirms the model's strong generalization performance. Conclusion: In this study, we successfully applied a neural network model based on deep learning that effectively performs automatic segmentation of ameloblastoma. The proposed method offers notable advantages in terms of efficiency, accuracy, and speed, rendering it a promising tool for clinical diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Unicystic ameloblastoma is a distinct entity of ameloblastoma characterized by slow growth and locally aggressive behavior. This retrospective study aimed to assess the efficacy of different treatment modalities of unicystic ameloblastoma, focusing on clinico-radiological and histopathological features. Data from patients diagnosed with unicystic ameloblastoma were retrospectively analyzed. Patients were categorized into luminal and intraluminal (Group A) and mural (Group B) variants based on the Ackermann classification, which has a significant influence on their biological behavior, treatment approaches, and prognosis. Patients in Group A underwent enucleation with chemical cauterization, peripheral ostectomy, and iodoform packing, whereas those in Group B were treated with resection and reconstruction. Post-operatively, the patients were subjected to radiographic assessments via digital orthopantomogram at regular intervals. Because of the rarity of unicystic ameloblastoma, only 17 patients were included in the study (Group A: 9 patients; Group B: 8 patients), with a mean follow-up of 4.9 years (range: 1.4–11.8 years). The primary outcome measure was the absence of recurrence, which indicated treatment success. No patient in either group experienced recurrence within the follow-up period. This study provides evidence supporting the successful treatment of luminal and intraluminal variants of unicystic ameloblastoma in young individuals using a conservative approach. However, the more aggressive mural variant demonstrated favorable outcomes with radical treatment. These findings emphasize the importance of the Ackermann classification in guiding treatment decisions for unicystic ameloblastoma and contribute valuable insights into optimizing therapeutic strategies based on clinico-radiological and histopathological findings. [ABSTRACT FROM AUTHOR]

The purpose of this multicentre study was to evaluate the efficacy of the 'dredging–marsupialization–curettage' (D–M–C) strategy in the treatment of conventional intraosseous ameloblastoma of the mandible. A total of 31 patients from three institutions, who had a pathological diagnosis of conventional ameloblastoma of the mandible, were treated with the D–M–C strategy. The surgical protocol comprised a dredging and marsupialization (D–M) step, with additional D–M steps as required. The patients then underwent curettage (C) once an obvious effect of the D–M step had been achieved during follow-up. Eight patients were followed up for ≥36 months but <60 months, while 23 were followed up for ≥60 months. Nineteen of the 23 patients followed up for ≥60 months were disease-free at the last follow-up, with no evidence of recurrence. The D–M step is effective for reducing the tumour size and preserving vital structures. The D–M–C surgical strategy may be a feasible treatment option for conventional ameloblastoma of the mandible. [ABSTRACT FROM AUTHOR]

A dentinogenic ghost cell tumor (DGCT) is a rare benign odontogenic tumor that commonly shows characteristics of solid proliferation and has a relatively high risk of recurrence after surgical treatment. We herein report a case of a central DGCT that occurred in the maxilla and resulted in bone expansion. This study highlights new imaging findings (particularly magnetic resonance imaging) along with histopathological observations. In addition, we conducted a review of the existing literature on this rare tumor. A 37-year-old man developed swelling around the right cheek. A benign odontogenic tumor such as ameloblastoma was suspected based on the imaging examination findings (including bone expansion and the internal characteristics of the tumor) on panoramic imaging, computed tomography, and magnetic resonance imaging. The lesion was surgically excised from the right maxilla. Postoperative histopathological examination led to a definitive diagnosis of central DGCT. The tumor comprised epithelial neoplastic islands, resembling ameloblastoma, inside tight fibroconnective tissue; masses of ghost cells and formation of dentin were also observed. We had suspected that the minute high-density region around the molars on the imaging examinations represented alveolar bone change; however, it represented dentin formation. This led to difficulty diagnosing the lesion. Although DGCT may present characteristic findings on imaging examinations, its occurrence is infrequent, and in some cases, the findings may include the presence or absence of an impacted tooth without obvious calcification. The present case suggests that we should consider the possibility of an odontogenic tumor with calcification when high-density structures are observed inside the lesion. [ABSTRACT FROM AUTHOR]

Ameloblastic carcinoma is a rare malignant odontogenic tumor that is further classified into being primary or secondary arising from a preexisting benign ameloblastoma. It affects the mandible in two thirds of the patients. There is no standard treatment protocol for this lesion but radicalsurgical excision with or without radiotherapy is reported in the majority of cases. In this paper, we present a case of a 22 year old male diagnosed with Ameloblastic carcinoma of the mandible with a clinical course of typical aggressiveness and extensive destruction. Histopathological examination of the incised biopsy showed a parakeratinized stratified squamous epithelium with underlying fibrous connective tissue stroma. The stroma is highly myxomatous and exhibits islands of odontogenic epithelium and chronic inflammatory cell infiltrates. Interlacing strands of odontogenic epithelium shows stellate reticulum-like cells and occasional areas of squamous metaplasia with cellular and nuclear pleomorphism. In addition, mitotic figures were noted. With the correlation of clinical, radiographic, and histological features, the lesion is diagnosed as ameloblastic carcinoma. The lesion was surgical excised and post-treatment follow-up for 6 months revealed no recurrence of the malignancy.

Adenoid ameloblastoma (AA) was recently recognised as a separate tumour type in the most recent World Health Organisation (WHO) classification of head and neck tumours. This decision has been considered controversial by several groups, who have described AA as a subtype of ameloblastoma, a hybrid odontogenic tumour or to fall within the spectrum of other recognised odontogenic tumours, including dentinogenic ghost cell tumour and adenomatoid odontogenic tumour. Here we review the reasons for the WHO decision to classify AA as a separate tumour type. We also critique molecular and histological findings from recent reports published since the WHO classification. While acknowledging that the classification of tumours is constantly evolving, the balance of current evidence suggests that AA should remain a distinct tumour type, and not a subtype of ameloblastoma, pending further molecular characterisation. [ABSTRACT FROM AUTHOR]

Simple Summary: Ameloblastoma is a type of tumor that usually forms in the jaw; while typically benign, it grows aggressively and often recurs after treatment. Traditional treatment involves extensive surgery, which can significantly affect a patient's quality of life. Recent research has focused on a new approach, targeting a specific cellular pathway known as the MAPK pathway, which appears to be involved in the development of these tumors. In this study, we reviewed the outcomes of 23 patients treated with this targeted therapy to assess its safety and effectiveness. The results were promising: most patients experienced significant tumor reduction, and the side effects were generally mild. This suggests that MAPK pathway inhibitors could be a viable alternative to surgery, potentially offering improved outcomes for patients with ameloblastoma, minimizing surgical risks, and preserving quality of life. This advancement could greatly impact the approach to treating this challenging condition. Ameloblastoma, a benign yet aggressive odontogenic tumor known for its recurrence and the severe morbidity from radical surgeries, may benefit from advancements in targeted therapy. We present a case of a 15-year-old girl with ameloblastoma successfully treated with targeted therapy and review the literature with this question: Is anti-MAPK targeted therapy safe and effective for treating ameloblastoma? This systematic review was registered in PROSPERO, adhered to PRISMA guidelines, and searched multiple databases up to December 2023, identifying 13 relevant studies out of 647 records, covering 23 patients treated with MAPK inhibitor therapies. The results were promising as nearly all patients showed a positive treatment response, with four achieving complete radiological remission and others showing substantial reductions in primary, recurrent, and metastatic ameloblastoma sizes. Side effects were mostly mild to moderate. This study presents anti-MAPK therapy as a significant shift from invasive surgical treatments, potentially enhancing life quality and clinical outcomes by offering a less invasive yet effective treatment alternative. This approach could signify a breakthrough in managing this challenging tumor, emphasizing the need for further research into molecular-targeted therapies. [ABSTRACT FROM AUTHOR]

Ameloblastoma is a non-cancerous but aggressive oral tumor emerging from odontogenic epithelial tissue involved during odontogenesis. Since there is lack in unravelling the complete molecular pathogenesis of ameloblastoma, chemotherapy is less attempted and a lot of disagreement over the optimal treatment option. Hence, till date, wide surgical resection is considered to be the reliable treatment for ameloblastoma. The Neurotrophin Signaling pathway plays an important role in neuron signaling and it is closely related with the MAPK pathway, which on the other hand regulated cell differentiation, apoptosis, proliferation, plasticity and survival. Protein- Protein Interaction analysis was analysed with STRING tool using WNL value, identified that CTNNB1, HRAS, NGFR, NGFR, and SORT1 having high interacting with BDNF, NT4, p75NTR, NGF, and NT3. The results of ontology analysis revealed that Neurotrophin signaling pathway is associated with Cell surface receptor signaling pathway, regulation of cell differentiation, regulation of development process, EGFR tyrosine kinase inhibitor resistance, MAPK signaling pathway, PI3K-Akt signaling pathway and Ras signaling pathway leading to pathogenesis involving genes. Further, clustering coefficient values of proteins BDNF, NT4, p75NTR, NGF & NT3 were identified as 0.627, 0.708, 0.367, 0.644 & 0.415. The results of molecular docking studies revealed among the selected ligands Methyl-ɣ-oresellinate, N-(4-Hydroxy-phenyl)-2-phenyl-N-phenylacetyl-acetamide, Atranorin and Oresellinate exhibited high binding affinity with selected protein. The key genes involved in Neurotrophin signaling pathway leading to ameloblastoma pathogenesis is revealed, which are closely associated with cell differentiation, cell proliferation, pro-apoptosis, and pro-survival regulations. Further it can be concluded that Neurotrophin signaling pathway could be one of the promising pathway to tailor the targeted drug therapy for Ameloblastoma treatment. [ABSTRACT FROM AUTHOR]

(1) Introduction and Aim: Surgical navigation has evolved as a vital tool in maxillofacial surgery, offering precise and patient-specific data. This study explores the clinical applications and accuracy of intraoperative tool tracking in maxillofacial surgery. (2) Materials and Methods: The research includes 42 patients with various pathologies who underwent surgeries assisted by a surgical navigation system using tracked instruments. Four representative cases are exhibited in the study: the first case involving coronoid hyperplasia with mouth opening deficit, the second case addressing naso-orbital-ethmoidal-frontal ossifying fibroma resection, the third case showcasing a subapical osteotomy (Köle) for a class III dentoskeletal malocclusion, and the fourth one exposing the treatment of a recurrent ameloblastoma. (3) Results: The results indicate that surgical navigation with tracked instruments provides high precision (<1.5 mm error), reduced surgical time, and a less invasive approach. (4) Conclusions: This study highlights the potential for reproducible outcomes and increased safety, especially in complex cases. Despite some limitations, the synergy between surgical navigation and tracked instruments offers a promising approach in maxillofacial surgery, expanding its applications beyond current practices. [ABSTRACT FROM AUTHOR]

In the 2022, World Health Organisation classification of odontogenic tumours, the clear cell odontogenic carcinoma is designated as a malignant odontogenic tumour with high recurrence and aggressive behaviour. Deceptive behaviour in the context of a wide range of differentials presents a significant diagnostic problem. It is the fifth most commom type of malignant odontogenic tumor. A systematic assessment of published cases, case series, and retrospective investigations of diagnostic significance of EWSR1 gene in clear cell odontogenic carcinoma is presented to determine trends in presentation, diagnostic characteristics, treatment, and patient outcome. To locate papers reporting clear cell odontogenic carcinoma and EWSR1, extensive database searches were carried out. Demographics, tumour location, immunohistochemical and molecular tests, treatment, follow-up, and recurrence were the variables. 34 cases were detected; 52.9% (n = 18) of the cases were females. The average age was 62.5 years, with a range of 43–82 years. The average size ranged from 3.4 to 8 cm. The mandibular body was the most common location, followed by the maxilla. Maximum immunohistochemistry positivity revealed by CK 19, CKAE1/3, EMA and p63. Most common gene fusion detected was EWSR1-ATF1 in 62.4% of cases contributing to its diagnostic attributes. Surgical treatment was used in 97% of cases. The average follow-up period was 30.3 months, and recurrence was reported in 52.4% of the cases. CCOC can metastasize, and the prognosis is fair. This is first systematic review, where we have attempted to consolidate the mutational expression of EWSR1 in Clear cell odontogenic carcinoma. It is difficult to identify from other clear cell tumours of the head and neck region. It is crucial to distinguish it from other clear cell lesions because of its aggressiveness. [ABSTRACT FROM AUTHOR]

Ameloblastoma (AM), periapical cyst (PC), and chronic suppurative osteomyelitis (CSO) are prevalent maxillofacial diseases with similar imaging characteristics but different treatments, thus making preoperative differential diagnosis crucial. Existing deep learning methods for diagnosis often require manual delineation in tagging the regions of interest (ROIs), which triggers some challenges in practical application. We propose a new model of Wavelet Extraction and Fusion Module with Vision Transformer (WaveletFusion-ViT) for automatic diagnosis using CBCT panoramic images. In this study, 539 samples containing healthy (n = 154), AM (n = 181), PC (n = 102), and CSO (n = 102) were acquired by CBCT for classification, with an additional 2000 healthy samples for pre-training the domain-adaptive network (DAN). The WaveletFusion-ViT model was initialized with pre-trained weights obtained from the DAN and further trained using semi-supervised learning (SSL) methods. After five-fold cross-validation, the model achieved average sensitivity, specificity, accuracy, and AUC scores of 79.60%, 94.48%, 91.47%, and 0.942, respectively. Remarkably, our method achieved 91.47% accuracy using less than 20% labeled samples, surpassing the fully supervised approach's accuracy of 89.05%. Despite these promising results, this study's limitations include a low number of CSO cases and a relatively lower accuracy for this condition, which should be addressed in future research. This research is regarded as an innovative approach as it deviates from the fully supervised learning paradigm typically employed in previous studies. The WaveletFusion-ViT model effectively combines SSL methods to effectively diagnose three types of CBCT panoramic images using only a small portion of labeled data. [ABSTRACT FROM AUTHOR]

Odontogenic tumors arise in the jawbone and originate from cells associated with tooth development. Therefore, understanding odontogenic tumors requires knowledge of all aspects of dental research, including tooth development and eruption. Ameloblastoma is the most common odontogenic tumor. Although a benign tumor, ameloblastoma progresses with marked jawbone resorption. Because of its locally aggressive features, it can be treated surgically by resecting the surrounding bone. From a molecular pathology perspective, several genetic mutations and dysregulated signaling pathways involved in ameloblastoma tumorigenesis have been identified. Histopathologically, ameloblastomas consist of peripheral ameloblast-like cells and an inner stellate reticulum. The stromal region consists of fibrovascular connective tissue, showing a characteristic sparse myxoid histology. In general, the tumor microenvironment, including the surrounding non-tumor cells, contributes to tumorigenesis and progression. In this review, we focus on the tumor microenvironment of ameloblastomas. In addition, we present some of our recent studies on osteoclastogenesis, tubulin acetylation-induced cell migration, and hypoxia-induced epithelial–mesenchymal transition in ameloblastomas. Further research on ameloblastomas can lead to the development of new treatments and improve patients' quality of life. [ABSTRACT FROM AUTHOR]

Odontogenic bone tumor (OT) is a rare pathology in the world, but it is very common in developing countries; its etiology is still unknown, and it causes serious deformities of the mandible and maxilla if it is not operated upon soon. Lassa virus (LASV) belongs to the Arenaviridae family, and its reservoir is a rodent of the genus Mastomys. The transmission of the LASV to humans can occur through ingestion or inhalation by contact with dirty objects, the consumption of contaminated food, or exposure to wounds, as rodents shed the virus in their urine and excrement. In this observational study, we aim to evaluate the presence of LASV in OT patient tissues collected in the Democratic Republic of the Congo. For this purpose, a group of nine patients affected by OT were enrolled, and the tissues derived from the surgery were collected. In total, 81.5% of the tissues were positive for LASV presence. Interestingly, we found that not only was the tumor LASV-positive, but in some cases, the bone was close to the tumor and the oral mucosa lining. These preliminary data could suggest the hypothesis that LASV may be involved with the onset of OT. [ABSTRACT FROM AUTHOR]

Ameloblastic fibrodentinoma (AFD) is a rare benign odontogenic tumor that resembles an ameloblastic fibroma with dysplastic dentin. This report presents a rare case of mandibular AFD with imaging features in a young patient. Panoramic radiography and computed tomography revealed a well-defined lesion with internal septa and calcified foci, causing inferior displacement of the adjacent molars as well as buccolingual cortical thinning and expansion of the posterior mandible. The lesion was surgically removed via mass excision, and the involved tooth was extracted under general anesthesia. During the 5-year follow-up period, no evidence of recurrence was observed. Radiologic features of AFD typically reveal a moderately to well-defined mixed lesion with varying degrees of radiopacity, reflecting the extent of dentin formation. Radiologists should consider AFD in the differential diagnosis when encountering a multilocular lesion with little dense radiopacity, particularly if it is associated with delayed eruption, impaction, or absence of involved teeth, on radiographic images of young patients. [ABSTRACT FROM AUTHOR]

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

Background: Ameloblastoma (AM) is a benign tumor locally originated from odontogenic epithelium that is commonly found in the jaw. This tumor makes aggressive invasions and has a high recurrence rate. This study aimed to investigate the differentially expressed genes (DEGs), biological function alterations, disease targets, and existing drugs for AM using bioinformatics analysis. Methods: The data set of AM was retrieved from the GEO database (GSE132474) and identified the DEGs using bioinformatics analysis. The biological alteration analysis was applied to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Protein-protein interaction (PPI) network analysis and hub gene identification were screened through NetworkAnalyst. The transcription factor-protein network was constructed via OmicsNet. We also identified candidate compounds from L1000CDS2 database. The target of AM and candidate compounds were verified using docking simulation. Results: Totally, 611 DEGs were identified. The biological function enrichment analysis revealed glycosaminoglycan and GABA (γ-aminobutyric acid) signaling were most significantly up-regulated and down-regulated in AM, respectively. Subsequently, hub genes and transcription factors were screened via the network and showed FOS protein was found in both networks. Furthermore, we evaluated FOS protein to be a therapeutic target in AMs. Candidate compounds were screened and verified using docking simulation. Tanespimycin showed the greatest affinity binding value to bind FOS protein. Conclusions: This study presented the underlying molecular mechanisms of disease pathogenesis, biological alteration, and important pathways of AMs and provided a candidate compound, Tanespimycin, targeting FOS protein for the treatment of AMs. [ABSTRACT FROM AUTHOR]

Introduction. A postsurgical ciliated cyst (PSCC) is an epithelial cyst that usually develops in the maxilla, although in rare cases, it can affect the mandible or other facial bones. The typical age of diagnosis is 40-50 years, with no gender prevalence, and the mean cyst development occurs approximately 10-15 years following a surgical or traumatic event. Some epithelial respiratory cells can be trapped into the bone tissue during maxillary surgical procedures or maxillary fractures. The pathogenetic mechanism can be attributed to an inflammatory process that stimulates epithelial proliferation, leading to cyst expansion caused by osmotic pressure difference. Methods. This study presents case series involving three surgical ciliated cysts located in the left maxilla, affecting two female patients (aged 49 and 55 years) and one male patient (aged 39 years). In all three cases, symptoms such as pain or swelling were mild and not consistently present. Two cases showed cyst development 10 and 15 years after implant placement, while one case was not associated with any surgical or traumatic event. CT scan identified well-defined unilocular lesions in the maxillary bone in each patient. Results. Histopathological examination of the surgical specimens confirmed the suspected diagnosis of a PSCC of maxilla. The cystic walls consisted of fibrous connective tissue with chronic inflammatory infiltrate, lined exclusively by a thin layer of ciliated pseudostratified columnar epithelium. In the third patient, it was not possible to rule out an unusual radicular cyst. Conclusions. Although PSCCs are not commonly encountered in daily practice, clinicians should consider this possibility including it in the differential diagnosis of odontogenic jaw cysts and benign jaw tumors, particularly in patients who have undergone previous surgeries in the maxillary area. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of key pathogenic genes involved in the development of jaw ameloblastoma (AB) and its associated extracellular matrix (ECM) on osteogenic differentiation in order to provide a theoretical foundation for future research into bone aggressiveness of AB. Methods: The essential genes were identified by five AB patients for whole‐exome sequencing and the microarray datasets GES38494 and GES132472. Moreover, the expression of key genes and their encoded proteins in AB tissues was explored. In addition, AB‐derived the decellularized ECM (ABdECM) tissues were generated by the decellularization technique. Furthermore, the osteogenic development of periodontal ligament stem cells (PDLSCs) was mimicked by simulating the effects of the AB tumor microenvironment (TME). Results: The AB essential genes including COL1A2, COL4A2, FBN1, and HPSE were discovered. Among them, the expression of HPSE was down‐regulated, while that of COL1A2, COL4A2, and FBN1 was noticeably upregulated in AB compared with normal gingival tissues of the jaws. In vitro osteogenic differentiation of PDLSCs was suppressed by the ABdECM. Conclusions: Abnormal ECM proteins encoded by COL4A2, COL1A2, FBN1, and HPSE genes can cause disturbance in the ECM environment of AB and promote bone resorption. [ABSTRACT FROM AUTHOR]

Odontogenic tumors (OTs) are distinct conditions that develop in the jawbones, exhibiting diverse histopathological features and variable clinical behaviors. Unfortunately, the literature on this subject in Saudi Arabia remains sparse, indicating a pressing need for more comprehensive data concerning the frequency, demographics, treatment modalities, and outcomes of OTs. Objectives: The study aims to evaluate the frequency, demographic features, treatment, and outcomes of OTs across three tertiary medical centers. Methods and Material: OT cases were identified in King Abdulaziz Medical City (KAMC), King Fahad Medical City (KFMC), and Prince Sultan Military Medical City (PSMMC) from January 2010 to December 2021. Results: Ninety-two OT cases were identified from the anatomical pathology laboratories of three tertiary hospitals. KFMC contributed the highest number of cases (43.5%), followed by KAMC (30.4%) and PSMMC (26.1%). The median age of OT patients was 29 years (range: 5–83), with males representing more than half of the patients (56.5%). The mandible was the most frequent site of OT occurrence (72.5%), with ameloblastoma being the predominant OT (63.0%), followed by odontoma (19.5%). Among the treatment modalities, bone resection was employed the most (51.0%), followed by enucleation (25.6%). Notably, 11.5% of OT cases with available follow-up data exhibited recurrence, with ameloblastoma accounting for eight recurrent cases. Conclusions: Although OTs are relatively common in the jaws, they are rare in anatomical pathology laboratories and the general population. This study contributes valuable insights into the epidemiology characteristics, treatment trends, and recurrence rates of OTs in Saudi Arabia. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 1-year-old feline with maxillary mass in a 1-year-old feline, with topics including the history of the mass, clinical and gross findings, and diagnostic imaging findings. The history includes the excision of the mass three years prior, followed by progressive swelling, dysphagia, and epiphora. Transgingival fine needle aspirate showed blood and mild mixed inflammation.

Ameloblastoma (AM) is a benign, although aggressive, epithelial odontogenic tumour originating from tooth‐forming tissues or remnants. Its aetiopathogenesis remains unclear; however, molecular analysis techniques have allowed researchers to progress in understanding its genetic basis. The high frequency of BRAF p.V600E as a main driver mutation in AM is well established; nevertheless, it is insufficient to explain its tumourigenesis. In this review, we aimed to integrate the current knowledge about the biology of AM and to describe the main genetic alterations reported, focusing on the findings of large‐scale sequencing and gene expression profiling techniques. Current evidence shows that besides BRAF mutation and activation of the MAPK pathway, alterations in Hedgehog and Wnt/β‐catenin pathway‐related genes are also involved in AM pathogenesis. Recently, a tumour suppressor gene, KMT2D, has been reported as mutated by different research groups. The biological impact of these mutations in the pathogenesis of AM has yet to be elucidated. Further studies are needed to clarify the impact of these findings in the identification of novel biomarkers that could be useful for diagnosing, classifying, and molecular targeting this neoplasm. [ABSTRACT FROM AUTHOR]

An approximately 30-year-old intact female Asiatic black bear (Ursus thibetanus) was presented for annual examination and a history of ptyalism. A large 9.5 cm × 5 cm × 5 cm, firm, round mass was identified attached to the hard palate on physical examination. A computed tomography scan was performed, and the heterogeneous, mineral-attenuating mass was seen arising from the right aspect of the palatine bone and extending rostrally to the level of the last maxillary molars, caudally into the oropharynx, and dorsally into the nasal choana. Surgical debulking was performed to remove the portion of the mass within the oral cavity. Histopathologic analysis was consistent with a keratinizing ameloblastoma. Nine months postoperatively, the patient was asymptomatic for the tumor. The patient was euthanized 23-months postoperatively, and severe diffuse pustular dermatitis, growth of the ameloblastoma on the hard palate, and various degenerative and aging changes were noted on necropsy at that time. This is the first report of an ameloblastoma in a member of the Ursidae family. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Almost 60% of mucoepidermoid carcinomas (MEC) are found in salivary glands, and 2-4% of all mucoepidermoid carcinomas are intraosseous (central) mucoepidermoid carcinomas (CMC). The treatment for these is most frequently surgical resection with long-term follow-up.10 OBJECTIVES: The primary objective in this case is to obtain a differential diagnosis. Based upon the clinical and pathological features observed, to then arrive at a diagnosis. METHODS: This case utilized microscopic examination with clinical and radiographic correlation to reach a definitive diagnosis that led to appropriate treatment. After an initial patient examination, an immediate referral was determined to be Indicated. An incisional biopsy was performed, which included the gingival lesion and the enucleated mass. RESULTS: The tumor consisted of solid and cystic components. Histologically appearing mucous cells were confirmed to be mucicarmine positive. Surgical treatment consisted of tumor removal, jaw resection, and neck dissection. Plastic surgery included bone graft utilizing the right fibula. Radiation therapy followed at two weeks. Seven months post-surgery, the patient was seen for dental treatment and prosthetic placement. CONCLUSION: Five years and 5 months post-surgery, the patient was seen at the dental school for reevaluation. She reported no recurrence of the tumor at that time; however, she complained of residual, lingering discomfort, tongue numbness and deviation, and neck stiffness. [ABSTRACT FROM AUTHOR]

Introduction: Ameloblastoma is one of the most frequent benign odontogenic tumours of the jaw, accounting for approximately 10% of all tumours in the mandible and maxilla. It is a slow‐growing, locally invasive tumour that causes painless swelling of the jaw or maxilla. Diagnosis: Ameloblastoma is diagnosed through computerised tomography imaging and a biopsy. A biopsy can help distinguish ameloblastoma from other cancers, such as ossifying fibroma, osteomyelitis, giant cell tumour, cystic fibrous dysplasia, myeloma, and sarcoma. Treatment: Ameloblastoma is best treated with vigorous en bloc excision and concomitant repair. Ameloblastoma therapy has long been plagued by high recurrence rates and extensive tissue abnormalities. Recent molecular findings strongly imply that ameloblastoma patients may benefit from targeted treatment. We offer a case report of unicystic ameloblastoma with a step‐by‐step customised therapeutic plan that prioritises patients' desire. [ABSTRACT FROM AUTHOR]

Adenoid ameloblastoma with dentinoid had been perceived as a rare odontogenic tumor with bridging histopathological features between ameloblastoma and adenomatoid odontogenic tumor. Due to the mixture of histopathological features of two separate and well-recognized entities, adenoid ameloblastoma was also regarded as a hybrid lesion. The diversity in the histopathological presentation among the cases has disaccorded the nature, behaviour, and prognosis of this pathology. Despite the literature acknowledging the histopathological diversity, categorizing all these variations into one and addressing them as a single entity was lagging till the 5th edition of the odontogenic tumor classification by the WHO was forwarded. With the establishment of the new terminology of adenoid ameloblastoma and the enlistment of its diagnostic criteria, the scientific literature has advocated updating, contributing, and redefining the various aspects of this pathology. Here, we present a case of a 34-year-old male who presented with a chief complaint of swelling in the lower front region of his jaw in the past one month. The swelling was associated with pain that was sudden in onset with a progressive increase in size. The swelling was also associated with discharge that resembled pus. A panoramic radiograph showed a mixed radiopaque and radiolucent area, extending from the distal aspect of 32 up to the distal aspect of 43. The entire cystic lining along with the growth was excised and sent for histopathological examination. Correlating clinically, the histopathological features are suggestive of adenoid ameloblastoma. Scientific literature has stood as a boon to evidence-based practice. The diagnosis for the present case report is truly an outcome of the literature-based update which helped the diagnosis of the case as a separate entity rather than as a hybrid pathology. The goal was to enhance the understanding of the lesions in terms of their clinical characteristics and diverse histopathological morphology. [ABSTRACT FROM AUTHOR]

Ameloblastoma in dogs most often has a highly conserved acanthomatous cell morphology and is recognized as canine acanthomatous ameloblastoma (CAA) while conventional ameloblastoma (CA) makes up a smaller yet morphologically diverse group of epithelial odontogenic tumors. In humans, a rare desmoplastic histological subtype has distinctive clinical, radiological, and microscopic features. Desmoplastic ameloblastoma (DA) has not previously been described in dogs, although it has been rarely referenced in the veterinary literature. This is the first thorough description of a case series of DA in dogs and describes clinical presentation, diagnostic imaging findings, histopathological features for diagnosis, and treatment outcome. Clinically, DA most often presents as a mass or swelling in the rostral mandible or maxilla of middle age to older dogs. On diagnostic imaging, the lesion has a radiolucent or mixed pattern with well-defined borders and variable loculation. As a solid, fibrous tumor with obscured odontogenic epithelium, DA is challenging to diagnose histologically and can mimic several other oral tumors, both benign and malignant. As an ameloblastoma, the biological behavior of DA is locally destructive yet benign and prognosis is favorable following surgical excision. [ABSTRACT FROM AUTHOR]

Ameloblastic carcinoma is a rare malignant odontogenic tumor that is further classified into being primary or secondary arising from a preexisting benign ameloblastoma. It affects the mandible in two thirds of the patients. There is no standard treatment protocol for this lesion but radicalsurgical excision with or without radiotherapy is reported in the majority of cases. In this paper, we present a case of a 22 year old male diagnosed with Ameloblastic carcinoma of the mandible with a clinical course of typical aggressiveness and extensive destruction. Histopathological examination of the incised biopsy showed a parakeratinized stratified squamous epithelium with underlying fibrous connective tissue stroma. The stroma is highly myxomatous and exhibits islands of odontogenic epithelium and chronic inflammatory cell infiltrates. Interlacing strands of odontogenic epithelium shows stellate reticulum-like cells and occasional areas of squamous metaplasia with cellular and nuclear pleomorphism. In addition, mitotic figures were noted. With the correlation of clinical, radiographic, and histological features, the lesion is diagnosed as ameloblastic carcinoma. The lesion was surgical excised and post-treatment follow-up for 6 months revealed no recurrence of the malignancy. [ABSTRACT FROM AUTHOR]

Background Ameloblastoma is a rare odontogenic neoplasm frequently located in the mandible. Standard treatment involves radical bone resection and immediate reconstruction, causing functional, aesthetic, and psychological impairments. The BRAF V600E mutation is present in approximately 80% of mandible ameloblastomas, and BRAF inhibitors have demonstrated sustained responses in unresectable cases. Methods We identified ameloblastoma patients planned for ablative surgery and screened them for BRAF V600E mutation. Neoadjuvant BRAF inhibitors were offered to facilitate jaw preservation surgery. Retrospective data collection encompassed treatment regimens, tolerability, tumor response, and conversion to mandible preservation surgery. Results Between 2017 and 2022, a total of 11 patients received dabrafenib (n = 6) or dabrafenib with trametinib (n = 5). The median age was 19 (range = 10-83) years. Median treatment duration was 10 (range = 3-20) months. All (100%) patients achieved a radiological response. Ten (91%) patients successfully converted to mandible preservation surgery with residual tumor enucleation. One patient attained complete radiological response, and surgery was not performed. Among the 10 surgically treated patients, all exhibited a pathological response, with 4 achieving near complete response and 6 partial response. At a median follow-up of 14 (range = 7-37) months after surgery, 1 case of recurrence was observed. Grade 1-2 adverse effects were reported in 8 (73%) patients, with a single case of grade 3 (hepatitis). Dose modification was necessary for 3 patients, and 4 experienced treatment interruptions, while 1 patient permanently discontinued therapy. Conclusions Neoadjuvant BRAF inhibition may offer a safe and effective strategy for organ preservation in mandible ameloblastoma treatment. [ABSTRACT FROM AUTHOR]

Background: The primary lesions of the mandible have a wide range of pathological features but similar imaging appearances, which often pose a great diagnostic dilemma. Objective: To devise a diagnostic algorithm using audit information obtained by correlating clinical, radiological and pathological characteristics of mandibular lesions and subsequent histopathological diagnosis available. Methods: A total of 64 cases were taken. Out of the 64 cases, 4 (6 %) had only OPG available, 42 (65 %) cases had only CT and 5 (7.8 %) patients had only MRI available. Results: The most common lesions encountered were Ameloblastoma comprising of 25 cases (39 %), followed by Osteosarcoma-7 (10.9 %) and Odontogenic keratocyst-5 (7.8%). The majority of the cases had both OPG and CT done, whereas in 3 (4%) cases all three imaging modalities were performed. Conclusions: Imaging is very helpful in diagnosis of the primary lesion of the jaw. It gives a clue about the type of periosteal reaction and effect on the surrounding bone (lytic, blastic or mixed tumors). [ABSTRACT FROM AUTHOR]

Ameloblastoma is a rare odontogenic tumor which may be complicated by hypercalcemia in advanced disease. Tumoral parathyroid hormone-related peptide (PTHrP) production and local osteolysis from paracrine factors have been proposed as mechanisms. Mitogen-activated protein kinase (MAPK) inhibitors have been successfully used in ameloblastomas with BRAF V600E mutation to reduce symptoms and decrease tumor burden. Serum calcium has been observed to normalize following treatment with MAPK inhibitors; however, the response of PTHrP and markers of bone turnover has not been reported. We describe a case of a 55-year-old female with PTHrP-mediated hypercalcemia secondary to BRAF V600E-positive ameloblastoma with pulmonary metastases. Following treatment with dabrafenib and trametinib, the patient experienced the regression of pulmonary lesions and normalization of serum calcium, PTHrP, and markers of bone turnover. Tissue samples of ameloblastoma carrying BRAF V600E mutation are more likely to express PTHrP than tissue samples carrying wild-type BRAF. In our case, resolution of PTHrP-mediated hypercalcemia following initiation of BRAF/MEK inhibition provides additional evidence that the MAPK pathway contributes to PTHrP synthesis. It also raises the question of whether MAPK inhibitors would be effective in treating PTHrP-mediated hypercalcemia associated with other malignancies harboring BRAF V600E mutation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: Deep carious lesions and their complications are possible causes of odontogenic infections. Although their location and clinical symptoms may mimic non-odontogenic infections, they are characterised by specific features that are helpful in their diagnosis and treatment. It seems worthwhile to create their clinical and microbiological profile. Aim of the research: To compare the clinical and microbiological features of odontogenic and non-odontogenic infections. Material and methods: The study was based on the medical records of 403 patients affected by the diseases. Results and conclusions: There were statistically significant differences in the white blood cell count, the number of accompanying diseases, dysphagia and the occurrence of neck swelling, and the duration of hospitalisation between odontogenic and non-odontogenic infections. We identified the most common pathogens as well as the clinical parameters specific to these infections. Although bacterial distribution was similar in both groups with a predominance of aerobic cocci, non-odontogenic infections were characterised by a relatively high contribution of Staphylococcus aureus and Klebsiella pneumoniae in comparison to odontogenic infections. We also indicated submandibular and peritonsillar spaces as commonly involved fascial spaces in odontogenic and non-odontogenic infections, respectively. Circulatory diseases and connective tissue diseases were identified as a factor predisposing to odontogenic infections. Comorbidities are the most important risk factor for the development of odontogenic infections and their severe course requiring hospitalisation. [ABSTRACT FROM AUTHOR]