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Primordial odontogenic tumour is a recently categorised rare benign mixed epithelial and mesenchymal odontogenic tumour which occurs most frequently in first two decades of life. It is composed of cellular myxoid connective tissue lined by cuboidal to columnar odontogenic epithelium resembling inner enamel epithelium in early stages of tooth development. Here, we are presenting a unique case of bilateral primordial odontogenic tumour of mandible in a paediatric patient. [ABSTRACT FROM AUTHOR]

Purpose: This research aimed to investigate the relative frequency of odontogenic tumours (OT) and selected odontogenic cysts in a single oral pathology center in New Zealand from 2008 to 2023. Methods: Histopathological records from the Oral Pathology Centre, University of Otago (2008–2023) were examined to identify OT. Odontogenic keratocyst (OKC) and calcifying odontogenic cyst (COC), previously classified as OT were also included. Patient demographics, clinical details and histopathologic diagnoses were recorded. Data were analyzed using SPSS. Results: Of the 34,225 biopsies over the 15-year period, 1.8% were identified as OTs, COC and OKCs and accounted for 47%, 1.5% and 51.5% respectively. The most prevalent OT types were odontoma (43.7%), ameloblastoma (27%) and cemento-ossifying fibroma (7.5%). Malignant OT, ameloblastic carcinoma, constituted 1.4% of OT. The average age at diagnosis for OKC, COC and OT patients were 48.2 ± 20.9, 33.7 ± 23.3 and 28.9 ± 19.3 years. Overall, male and mandibular site predilections were observed. Recurrence of OKC and ameloblastoma occurred in 15.2% and 13.7% of patients. The time for recurrence for OKC and Ameloblastoma were 61.7 ± 56.5 months and 122 ± 152 months respectively. Conclusion: The demographic features and range of OT, COC and OKC in New Zealand align with those of other western countries. The study also confirms need for long term follow up for patient with OKC and ameloblastoma. [ABSTRACT FROM AUTHOR]

Background: This research aimed to investigate the concordance between clinical impressions and histopathologic diagnoses made by clinicians and artificial intelligence tools for odontogenic keratocyst (OKC) and Odontogenic tumours (OT) in a New Zealand population from 2008 to 2023. Methods: Histopathological records from the Oral Pathology Centre, University of Otago (2008–2023) were examined to identify OKCs and OT. Specimen referral details, histopathologic reports, and clinician differential diagnoses, as well as those provided by ORAD and Chat-GPT4, were documented. Data were analyzed using SPSS, and concordance between provisional and histopathologic diagnoses was ascertained. Results: Of the 34,225 biopsies, 302 and 321 samples were identified as OTs and OKCs. Concordance rates were 43.2% for clinicians, 45.6% for ORAD, and 41.4% for Chat-GPT4. Corresponding Kappa value against histological diagnosis were 0.23, 0.13 and 0.14. Surgeons achieved a higher concordance rate (47.7%) compared to non-surgeons (29.82%). Odds ratio of having concordant diagnosis using Chat-GPT4 and ORAD were between 1.4 and 2.8 (p < 0.05). ROC-AUC and PR-AUC were similar between the groups (Clinician 0.62/0.42, ORAD 0.58/0.28, Char-GPT4 0.63/0.37) for ameloblastoma and for OKC (Clinician 0.64/0.78, ORAD 0.66/0.77, Char-GPT4 0.60/0.71). Conclusion: Clinicians with surgical training achieved higher concordance rate when it comes to OT and OKC. Chat-GPT4 and Bayesian approach (ORAD) have shown potential in enhancing diagnostic capabilities. [ABSTRACT FROM AUTHOR]

Background: Odontogenic myxoma is one of the benign mesenchymal odontogenic tumours with aggressive behaviour and showed slow and asymptomatic expansion, the second until the third decade of life is the most targeted age group. With high female preponderance, about the management, surgical management is the only option concerning this odontogenic pathology with a variety of treatment options. This study aims to analyse a series of 37 patients with odontogenic myxoma treated in a single institution. Materials and method: In total, 37 patients with odontogenic myxoma were treated at KTDH in Sudan and were retrospectively reviewed. With the analysis of medical records of all patients diagnosed with odontogenic myxoma and the related variables, data were analysed using the SPSS statistical program (version 23). Results: Most of the cases were females (26 patients 70.27%), and males were about (11 patients 29.73%). In most of the cases maxilla was affected more than the mandible (25 cases, 67.57%) mostly in its posterior segment (32 cases, 86.49). The most age group affected was the group of cases (0–20) which were about 18 cases (48.65%). In total, 35 of the cases noticed swelling (94.59%), while 14 noticed tooth mobility (37.84%) and paraesthesia was a positive finding in just one case (2.70%). In total, 12 patients (32.43%) had a positive history of tooth extraction related to the lesion, and recurrence was positive in (64, 86%). Conclusion: Odontogenic myxoma is locally aggressive. There is no gold standard protocol for surgical treatment so choosing the most suitable and reliable treatment option relay on the operator taking into consideration the characteristic of each case and the recurrence rate with the associated postoperative impairments. [ABSTRACT FROM AUTHOR]

Background Differentiating between ameloblastoma (AB) and ameloblastic carcinoma (AC) is difficult, especially when AB has atypical cytological characteristics or an uncommon clinical history. This systematic review and meta-analysis aimed to elucidate the differential expression of immunohistochemical markers between AB and AC. Methods We conducted a thorough search of PUBMED and SCOPUS according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify cross-sectional studies that compared the expression of immunohistochemical markers in AB and AC. We used a random-effects model to analyze the risk ratios and their corresponding 95% confidence intervals (CIs). The quality of the included studies was assessed using the Newcastle-Ottawa scale. The Egger’s test was used to assess publication bias. Results In total, 301 articles were identified. After excluding irrelevant titles and abstracts, 86 articles were selected for full-text review. We categorized the 41 markers into proliferative and non-proliferative markers. Among non-proliferative markers, nuclear markers were differentially expressed in AB and AC. SOX2 was the only marker that significantly differentiated AB and AC, with an RR of -0.19 (CI 0.10-0.36, I2=0). Conclusion The current evidence suggests the significance of SOX2 in differentiating between AB and AC, warranting prospective confirmation in well-defined extensive studies. We highlight the paucity of high-quality replicated studies of other markers in this field. Collaborative efforts with standardized techniques are necessary to generate clinically useful immunohistochemical markers.

Ameloblastoma is the most common aggressive benign odontogenic tumour of the jaws. Ameloblastoma is a benign epithelial odontogenic tumour that typically arises in the mandible or maxilla. A clinical, radiographic and histopathological report is presented of a case of giant acanthomatous ameloblastoma in the left hemi mandible of a 46-year-old healthy lady. The histopathological examination of the removed specimen revealed the histopathological pattern of an acanthomatous ameloblastoma. The radiographic appearance of the lesion showed the presence of multilocular radiolucencies, which were crossing the midline, which is rarely found in ameloblastoma. Due to its rarity and lack of data, we take this opportunity to present a case of advanced acanthomatous ameloblastoma and its surgical challenges. [ABSTRACT FROM AUTHOR]

Background Differentiating between ameloblastoma (AB) and ameloblastic carcinoma (AC) is difficult, especially when AB has atypical cytological characteristics or an uncommon clinical history. This systematic review and meta-analysis aimed to elucidate the differential expression of immunohistochemical markers between AB and AC. Methods We conducted a thorough search of PUBMED and SCOPUS according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify cross-sectional studies that compared the expression of immunohistochemical markers in AB and AC. We used a random-effects model to analyze the risk ratios and their corresponding 95% confidence intervals (CIs). The quality of the included studies was assessed using the Newcastle-Ottawa scale. The Egger’s test was used to assess publication bias. Results In total, 301 articles were identified. After excluding irrelevant titles and abstracts, 86 articles were selected for full-text review. We categorized the 41 markers into proliferative and non-proliferative markers. Among non-proliferative markers, nuclear markers were differentially expressed in AB and AC. SOX2 was the only marker that significantly differentiated AB and AC, with an RR of -0.19 (CI 0.10-0.36, I2=0). Conclusion The current evidence suggests the significance of SOX2 in differentiating between AB and AC, warranting prospective confirmation in well-defined extensive studies. We highlight the paucity of high-quality replicated studies of other markers in this field. Collaborative efforts with standardized techniques are necessary to generate clinically useful immunohistochemical markers.

Hybrid odontogenic tumours occur rarely in the oral cavity. The basic histogenesis of these lesions is not clear. Hybrid odontogenic tumours characteristically exhibit two or more distinct morphological features that may lead to a diagnostic dilemma. Unicystic Ameloblastomas (UA) are the second most common odontogenic tumour. Ameloblastic Fibro-dentinoma (AFD) is a rare mixed odontogenic tumour. Both UA and AFD commonly occur in the second decade of life, may be asymptomatic with a slight female predilection, and predominantly occur in the mandibular posterior region. Herein, the authors report a rare case of a 15-year-old female patient complaining of swelling in the right lower posterior jaw region in the last two months. The lesion was surgically enucleated and sent for histopathological examination. On histopathological examination, the lesion exhibits areas of both UA and AFD, representing a rare occurrence of a hybrid odontogenic tumour. The present case report highlights the unique combination of two odontogenic tumours of different origins. [ABSTRACT FROM AUTHOR]

Background: CTNNB1 gene encodes beta catenin, a transcriptional activator of Wnt pathway involved in the pathogenesis of odontogenic lesions. Though located intramembranously, its translocation into cytoplasm and nucleus could trigger cell proliferation, inhibition of apoptosis, invasion and migration of the tumour cell. Materials and Methods: Five electronic databases including MEDLINE by PubMed, Google scholar, Scopus, Trip, Cochrane library and EMBASE until 1 January 2023 without period restriction were thoroughly searched. Those articles that identified CTNNB1 mutation and beta catenin in odontogenic lesions were included for review. Risk of bias was analysed for each study using QUADAS 2 tool and Review Manager 5.3 was used to output its result. Results: Thirty four published articles were included for data synthesis. A total of 1092 cases of odontogenic lesions were assessed for both CTNNB1 mutation and beta catenin expression. CTNNB1 mutation was observed in ameloblastoma, calcifying odontogenic cyst, calcifying cystic odontogenic tumour and all malignant odontogenic tumours. The beta catenin expression (nuclear and cytoplasmic) was maximum in odontogenic keratocyst and calcifying odontogenic cyst. The expression was variable in ameloblastomas, membranous in odontomas, calcifying cystic odontogenic tumour and nuclear in all malignant tumours. Discussion and Conclusion: High recurrence of odontogenic keratocyst and aggressiveness of solid ameloblastoma and malignant odontogenic tumours could be associated with the nuclear translocation of beta catenin. Disparity between CTNNB1 mutation and beta catenin expression within odontogenic lesions suggests alternate routes of beta catenin activation. The review results support the unique localisation of beta catenin as a helpful diagnostic factor in the pathogenesis of odontogenic lesions. [ABSTRACT FROM AUTHOR]

Background: Reports on the proteomic studies of ameloblastoma and other common odontogenic lesions are limited. We thus explored the differential proteins among ameloblastoma, odontogenic keratocyst, dentigerous cyst, and normal gingival tissue using proteomics and identified hub proteins involved in the local aggressiveness and recurrence of ameloblastoma. Methods: Samples were obtained from 14 patients with ameloblastoma, 6 with odontogenic keratocyst, 9 with a dentigerous cyst, and 5 with normal gingival tissue. Proteins were then extracted, purified, quantified, and analysed using Easy‐nLC chromatography and mass spectrometry. Further functional annotation and enrichment analyses were performed using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes on the target protein collection. Protein clustering and protein–protein interaction network analyses were used to screen the hub proteins. Proteins with significant interactions were screened according to their degree index. These results were verified by immunohistochemical staining. Proteins meeting the screening criteria of expression difference ploidy >1.2‐fold (upregulation and downregulation) and p < 0.05 were considered differential proteins. Results: In ameloblastoma, 808 differential proteins were upregulated and 505 were downregulated compared with those in odontogenic keratocyst; 309 were upregulated and 453 were downregulated compared with those in dentigerous cyst; and 2210 were upregulated and 829 were downregulated compared with those in normal gingival tissue. The three groups of differential proteins were associated with cellular exosomes, antigen binding, complement activation, human papillomavirus infection, focal adhesion, cell adhesion molecules, and metabolic pathways. Conclusion: CDH3 is associated with the local aggressiveness and recurrence of ameloblastoma and is a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Ameloblastoma are the benign, locally aggressive, slow growing solid or cystic neoplasms of the jaws containing odontogenic epithelium in a connective tissue stroma. Their polymorphous nature is reflected by the diversity of known histological patterns of presentation. The hemangiomatous ameloblastoma is the less commonly encountered histological pattern of ameloblastoma with increased vascularity. The presence of ameloblastoma in the maxillary area is rare entity, and the hemangiomatous variation of unicystic ameloblastoma in the anterior maxillary region has never been recorded in the literature. Authors hereby, present a case of a 22-year-old man who complained of swelling in the upper front tooth region with buccal cortical expansion and wispy trabeculation. This study is noteworthy since, it is the first to reveal the hemangiomatous type of unicystic ameloblastoma in the maxillary anterior region.

Peripheral odontogenic fibroma (POdF) is an uncommon benign tumour of mesenchymal origin being the soft tissue counterpart of central odontogenic fibroma. Due to its ordinary, non-distinctive clinical features, POdF is often clinically diagnosed as an oral reactive lesion as the latter is considerably more common. This article presents a case of 37-year-old man with a recurrent painless, reddish, sessile gingiva mass at the upper anteriors region. Clinical diagnosis of pyogenic granuloma was made as patient’s oral hygiene was fair with no significant radiographic findings. Excisional biopsy followed by histopathology examinations revealed the lesion to be POdF. To date, a paucity of information on POdF’s biological behaviour and recurrence rate poses significant diagnostic and therapeutic challenges. Histopathology examination of seemingly harmless gingival enlargement is highly recommended. [ABSTRACT FROM AUTHOR]

Primordial odontogenic tumour (POT) is a newly described benign mixed odontogenic neoplasm that has been included in the World Health Organization classification 2017. Only 19 cases that conform to the clinico-pathologic criteria for diagnosis have been reported worldwide. We present the 20th case of POT reported worldwide and is only the third case to be reported from India. The need for considering POT as a possible diagnosis in lesions affecting posterior mandible in patients below 10 years, the need for clinicians and pathologists to be aware of this entity and the need to draw more specific conclusions on the diagnostic criteria of POT make it necessary to report every single case of this entity from different parts of the world. Along with the case report in a 3-year-old child patient, we also present here a summary of the cases reported till date and the review of literature. [ABSTRACT FROM AUTHOR]

Odontogenic Keratocyst (OKC) is an odontogenic cyst of developmental origin arising from remnants of the dental lamina. Malignant or benign transformations though rare have been noticed from their epithelium. Ameloblastomatous transformation from an OKC is extremely rare with such lesions being referred to as combined/"hybrid" odontogenic lesions. In this article, we present an intriguing case of a 60-year-old male who was operated on for OKC of the anterior mandible 3 years before, who came back with a complaint of swelling over the same site. Incisional biopsy revealed the acanthomatous type of ameloblastoma for which segmental resection with immediate reconstruction using recon plate was done. Excision biopsy revealed a plexiform variant as well, thus exhibiting a hybrid pattern. Surgeons should be aware of this hybrid presentation of ameloblastoma arising from the epithelium of OKC as the acanthomatous subtype is known for its notorious genetic behavior leading to recurrence and aggressive nature of this tumor. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract Background Ectopic odontogenic tumours are rare and difficult to diagnose. Consequently, they are occasionally misdiagnosed as other tumours and overtreated. Dentinogenic ghost cell tumours (DGCTs) are odontogenic neoplasms characterised by a CTNNB1 mutation, ghost cell appearance, and dentinoid-like calcification. Herein, we present a case of ectopic DGCT on the floor of a patient’s mouth, providing reliable clinicopathological and genetic evidence of its odontogenicity for the first time. Case presentation A 72-year-old man presented with painless sublingual swelling. Imaging revealed a multi-lobulated, solid-cystic mass on the floor of his mouth. Cytological evaluation showed folded epithelial clusters composed of basaloid cells, keratinised material, and calcification. Histological analysis revealed a multi-cystic, cribriform to solid nest, with an odontogenic satellate reticulum-like epithelium, including ghost cells and dentinoid matrix deposition. Immunohistochemical analysis found that CK19, CK5/6, bcl-2, and p63 were diffuse positive, β-catenin was focal positive in the nuclei, and the cells in the dentinoid matrix were positive for DMP1. The CTNTTB1 mutation was detected, leading to the final diagnosis of ectopic DGCT. There was no recurrence during the 6-month follow-up. Conclusions Overall, we have presented a comprehensive clinical overview of DGCT and identified its pathological and genetic features. This report will aid in the recognition of this rare disease in the future and help to avoid misdiagnosis and overtreatment.

Simple Summary: Ameloblastoma is a benign odontogenic tumour, and the patient always presents at a later stage when the tumour is already in an aggressive state. The finding of high mutation of BRAF V600E indicates the need to explore the molecular pathogenesis of ameloblastoma. However, there is inconsistent evidence regarding this mutation occurrence and its association with clinical information. This systematic review and meta-analysis aim to pool the overall mutation prevalence of BRAF V600E in reported ameloblastoma cases and to determine its association with patient demographic and clinicopathological features. This meta-analysis shows that BRAF V600E mutation has a high pooled prevalence of 70.49% in ameloblastoma. Furthermore, there was a significant meta-analysis association for those younger than 54 years old and in the mandible. Researchers could utilise these findings to improve the treatment option and find a possible new biomarker for the early detection of ameloblastoma. The discovery that ameloblastoma has a high mutation incidence of BRAF V600E may enable a better investigation of pathophysiology. However, there is inconsistent evidence regarding this mutation occurrence and its association with clinical information. This systematic review and meta-analysis aim to pool the overall mutation prevalence of BRAF V600E in reported ameloblastoma cases and to determine its association with patient demographic and clinicopathological features. Following the PRISMA guidelines, a comprehensive article search was conducted through four databases (Scopus, Google Scholar, PubMed, and Web of Science). Seventeen articles between 2014 and 2022 met the inclusion criteria with 833 ameloblastoma cases. For each included study, the significance of BRAF V600E on the outcome parameters was determined using odd ratios and 95% confidence intervals. Meta-analysis prevalence of BRAF V600E in ameloblastoma was 70.49%, and a significant meta-analysis association was reported for those younger than 54 years old and in the mandible. On the contrary, other factors, such as sex, histological variants, and recurrence, were insignificant. As a result of the significant outcome of BRAF V600E mutation in ameloblastoma pathogenesis, targeted therapy formulation can be developed with this handful of evidence. [ABSTRACT FROM AUTHOR]

Fibromyxoma of the jaw is a very uncommon benign mesenchymal odontogenic tumour that can be aggressive locally. In the present report, a 14-year-old female patient presented to our college hospital with the complaint of swelling and pain. Initially, a panoramic radiograph indicated multilocular radiolucency, and a CBCT examination revealed buccal cortical plate erosion. Microscopic examination revealed odontogenic fibromyxoma after incisional and excisional biopsy. The clinical features, panoramic radiograph and histological findings of this case have all been covered in this article. [ABSTRACT FROM AUTHOR]

Aim: To introduce the reader to the rare solid odontogenic keratocyst (OKC) that is different from the classic OKC and may mimic other entities. Case report: We discuss a solid OKC occurring in the body of the mandible of a 59‐year‐old female, which was treated with a local excision. Discussion: The clinical, radiological and histological findings are discussed alongside the pertinent literature. Conclusion: Awareness of the solid OKC should ensure appropriate work‐up and management of this rare entity. [ABSTRACT FROM AUTHOR]

Introduction: The recent classification of odontogenic tumours includes the entities clear cell odontogenic carcinoma (CCOC) and clear cell ameloblastoma (CCAM) under the unifying name CCOC. The lack of ameloblastic differentiation in many cases of CCOC, its more aggressive behaviour and unique molecular profile suggest a distinct entity which merits its own standing in the classification of odontogenic carcinomas. Case report: A 53‐year‐old male presented with excessive hyperplastic tissue in the anterior maxilla. Microscopic examination disclosed a biphasic clear cell neoplasm with nests of polygonal clear cells, surrounded by intensely eosinophilic flattened cells. The tumour cells were immunoreactive for MNF 116, CK 14, CK 19, CK 5 and EMA. The proliferation index, Ki67, was low and its expression, similar to the basal‐cell‐specific cytokeratins (CK 14 and CK5), was confined to the peripheral cells. Molecular studies confirmed EWSR1 gene rearrangements. An anterior maxillectomy was performed, supplemented with radiotherapy. Three years after resection, multiple metastatic bodies were detected in the lung and the patient passed away 1 year later. Conclusion: This case further supports the notion that CCOC with biphasic histomorphology appears to have a high mortality rate, and it may be wise to treat and monitor these patients more aggressively. [ABSTRACT FROM AUTHOR]

The Adenomatoid Odontogenic Tumour (AOT) is more than 100 years old, known by different names and the term AOT was coined in 1969 by Philipsen and Birn. AOT frequently occurs in intra-osseous location in gnathic skeleton and rarely seen in peripheral forms. These are rare odontogenic tumours, accounting for 2.2--7.1% of all odontogenic tumours, whereas the central or intraosseous variant of AOT in follicular and extra-follicular presentation, accounts for 95.6% of all AOTs. The peripheral variant presents as a gingival mass, which may cause slight saucerization of alveolar bone or might not affect the bone at all. These peripheral variants constitute 4.4% or less, of all AOTs of the gnathic skeleton. Here, we present a rare case of a peripheral variant of AOT in a 35-years-old female, 1.5 to 2 cm in dimension seen on the labial gingiva in right canine-premolar area. The lesion showed marked bone loss in 13 and 14 teeth region, causing mobility of 13. Histopathology showed a well encapsulated tumour mass with metaplastic bone in the capsule. A conventional AOT with ductal and rosette pattern was seen with tumour droplets and amyloid like material. The case clinically presented a moderately aggressive behaviour. [ABSTRACT FROM AUTHOR]

Odontogenic lesions are a category of lesions, which are found to be arising from the remnants of the tooth-bearing tissues of the body, that can be cystic in nature as a result of degeneration or as a result of excessive proliferation of these cells, can result in the formation of odontogenic tumours which are found in gnathic bones in the body. Since their discovery in literature and the explanation provided for their pathogenesis, these lesions have been the subject of debate and controversy amongst researchers as well as practitioners. Thereby, this review has taken into consideration one such odontogenic tumour, Calcifying Cystic Odontogenic Tumour (CCOT), which first were included under the namesake (Calcifying odontogenic cyst) as a sperate subheading under this cyst, but now has been designated under the category of tumours along with various histologic subtypes classified and described henceforth. Although the lesion has been removed in the recent classification, a wide variety of lesions in biphasic form has been reported in the past. Therefore, this present review takes a sneak-peek into this lesion with insight into its presentation, incidence, aetiology, pathogenesis, histopathology and all the controversies surrounding this category of lesion and the current literature about this lesion with proving the fact that this needs to be considered again in the category of odontogenic tumours., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier Inc.)

Sclerosing Odontogrenic Carcinoma (SOC) is a recent addition to the category of odontogenic tumours, which was first described by Koutlas et al. in 2008. It was described as primary intraosseous carcinoma with bland cytology, sclerotic stroma with presence of local infiltration showing aggressive behaviour. Following its discovery and the presentation of first case, only a handful of cases have been reported till date, which may be due to underreporting of the cases or inclusion of the case to other diagnosis since the features of this tumour overlaps with many other lesions of the oral cavity. Due to this factor, the pathogenesis of this category of tumours still remains enigmatic. The clinical features as a result of this factor are also not reported of the consistent type and overlaps with the already existing clinical features of other lesions. This lesion has only appeared till date twice in WHO classification of Odontogenic Cysts and Tumours. Thereby, the literature on this category is still in paucity. Therefore, the present review takes into account all of the features, diagnostic criteria and the markers discovered for this lesion and would provide an insight into whether this lesion is justified as a malignant lesion or should not be considered as a separate category of odontogenic tumour., Competing Interests: Declaration of competing interest This is to hereby state that, the author, have no financial support for the publication or writing of this manuscript. All the authors have significantly contributed for the writing, revising and final formatting of the manuscript and the respective files attached with it. Also, the authors have no conflicts regarding the publication of this manuscript amongst themselves., (Copyright © 2024. Published by Elsevier Inc.)

Odontogenic myxofibroma is a benign tumour that is rarely encountered in any bone other than jaws. It accounts for only 3–11% of all odontogenic tumours. The pathogenesis of these tumours is still controversial and may arise from myxomatous degeneration or fibrous stroma or from the mesenchymal portion of the tooth germ. Clinically, they are slow-growing and can cause gradual expansion of the cortical plates, loosening, displacement of teeth, and rarely root resorption. Biologically, the tumour is locally aggressive with a high recurrence rate, which warrants extensive surgical treatment. Here, we present a case of central odontogenic myxofibroma in a 45-year-old female resulting in the extensive involvement of the mandible within a month. [ABSTRACT FROM AUTHOR]

Ameloblastoma are the benign, locally aggressive, slow growing solid or cystic neoplasms of the jaws containing odontogenic epithelium in a connective tissue stroma. Their polymorphous nature is reflected by the diversity of known histological patterns of presentation. The hemangiomatous ameloblastoma is the less commonly encountered histological pattern of ameloblastoma with increased vascularity. The presence of ameloblastoma in the maxillary area is rare entity, and the hemangiomatous variation of unicystic ameloblastoma in the anterior maxillary region has never been recorded in the literature. Authors hereby, present a case of a 22-year-old man who complained of swelling in the upper front tooth region with buccal cortical expansion and wispy trabeculation. This study is noteworthy since, it is the first to reveal the hemangiomatous type of unicystic ameloblastoma in the maxillary anterior region. [ABSTRACT FROM AUTHOR]

Cementoblastoma is a rare benign odontogenic neoplasm of mesenchymal origin. The benign cementoblastoma was previously classified as one of the cementoma neoplasias by the World Health Organisation’s (WHO) classification of odontogenic tumours. The benign cementoblastoma in 2005 has been added to the list of odontogenic tumours that involve “mesenchyme and/or odontogenic ectomesenchyme, with or without odontogenic epithelium”. It accounts for around 0.69-8% of all odontogenic tumours. The lesion usually is asymptomatic and slow growing causing cortical plate expansion of both buccal and lingual plates. Cementoblastoma has male predilection, commonly seen involving mandibular first molar diagnosed in early age. There are very few incidents of an infected cementoblastoma in the literature. Radiological examinations can reveal a blend of radiolucent and radiopaque mass presenting a wheel spoke pattern. The histopathological results for both cementoblastoma and osteoblastoma are comparable. The relationship of the lesion with the tooth is the distinguishing element. Hereby, authors present a case of infected cementoblastoma in a 51-year-old female patient involving impacted mandibular second molar, clinically aggressive with unique radiologic features. Cementoblastoma is usually an incidental finding while the present case was associated with an impacted tooth and was symptomatic with infection. The uniqueness of the present case was the complete involvement of the root structure and the cyst like expansion of the lesion instead of the usual thin radiolucent rim. Also, the lesion was infected with no dental caries associated with the tooth.

Purpose: To examine whether a difference exists in the relapse rate between the conservative and radical approaches after the treatment of solid/multicystic ameloblastoma (SMA), a systematic review of the literature based on evidence of the last decade was performed. Materials and Methods: The search strategy incorporated examinations of electronic databases, supplemented by hand searches. A search of four electronic databases, including Ovid MEDLINE, PubMed, EMBASE and Web of Science, was carried out for relevant studies published in the English language from January 2005 to September 2015. Cross referencing and hand research was used to identify further articles. Relative Risk (RR) as effect estimates was calculated in both fixed and random effects models. Results: Of 4234 abstracts screened, only 26 articles met the inclusion criteria and were screened in full text. Of these, only 4 were included in the final meta-analysis. Conclusion: The inverse of variance test revealed a statistical difference in the relapse rate for SMA treatment with the conservative vs radical approach. The higher recurrence rate after a conservative approach compared to the surgical approach is significant. However, this review cannot give any recommendation due to the lack of clinical evidence. [ABSTRACT FROM AUTHOR]

Abstract Background Malignant odontogenic tumours are extremely rare tumours occurring within the jaws. Our study was performed to determine the demographic and clinico-pathological features of malignant odontogenic tumours amongst a multi-ethnic Asian population. Methods This was a retrospective cross-sectional study of malignant odontogenic tumours diagnosed at the Institute for Medical Research, Malaysia, from 2009 to 2019. All cases were independently reviewed and reclassified following the criteria set out in the latest edition of the World Health Organization 2017 reference text. Demographic and clinico-pathological data were recorded for each case. Results Twenty-four cases of malignant odontogenic tumours were identified. The patients’ age ranged from 16 to 79 years with the mean age at diagnosis being 50.8 years (SD = 16.18). There was a male predominance (66.7%) in this cohort of patients. The ethnic distribution appeared to reflect the Malaysian population with most cases seen amongst the Malay ethnic group (66.7%). Ameloblastic carcinoma was the most frequently diagnosed malignant odontogenic tumour (45.8%) and was also predominantly seen in males (90.9%). All patients with clear cell odontogenic carcinoma were females. There was no obvious sex predilection in primary odontogenic carcinoma not otherwise specified (NOS). The mandible (79.2%) was more frequently involved compared to the maxilla. Conclusions Diagnosis and management of malignant odontogenic tumours are challenging due to the rarity of these tumours. Our study has elucidated the clinico-pathological features of malignant odontogenic tumours seen in a multi-ethnic Asian population.

Background: Ectopic odontogenic tumours are rare and difficult to diagnose. Consequently, they are occasionally misdiagnosed as other tumours and overtreated. Dentinogenic ghost cell tumours (DGCTs) are odontogenic neoplasms characterised by a CTNNB1 mutation, ghost cell appearance, and dentinoid-like calcification. Herein, we present a case of ectopic DGCT on the floor of a patient's mouth, providing reliable clinicopathological and genetic evidence of its odontogenicity for the first time. Case presentation: A 72-year-old man presented with painless sublingual swelling. Imaging revealed a multi-lobulated, solid-cystic mass on the floor of his mouth. Cytological evaluation showed folded epithelial clusters composed of basaloid cells, keratinised material, and calcification. Histological analysis revealed a multi-cystic, cribriform to solid nest, with an odontogenic satellate reticulum-like epithelium, including ghost cells and dentinoid matrix deposition. Immunohistochemical analysis found that CK19, CK5/6, bcl-2, and p63 were diffuse positive, β-catenin was focal positive in the nuclei, and the cells in the dentinoid matrix were positive for DMP1. The CTNTTB1 mutation was detected, leading to the final diagnosis of ectopic DGCT. There was no recurrence during the 6-month follow-up. Conclusions: Overall, we have presented a comprehensive clinical overview of DGCT and identified its pathological and genetic features. This report will aid in the recognition of this rare disease in the future and help to avoid misdiagnosis and overtreatment. [ABSTRACT FROM AUTHOR]

Unicystic ameloblastoma is a distinct pathological variant with varying evidence published about its behaviour and surgical management. Due to a paucity of large studies in the literature with long-term follow up, the aim of this study was to analyse its surgical management and identify clinicopathological features associated with recurrences. All histopathologically confirmed lesions diagnosed at two referral centres between 1995 and 2020 were retrospectively analysed. Demographic, clinical, radiological, and histopathological features were analysed along with surgical methods and follow-up data. Univariate regression analyses were performed to identify risk factors for recurrence. Sixty-three patients were included in the study with mean age of 26.3 years and a male to female ratio of 1:0.75. The majority of lesions occurred in the posterior mandible (57.1%) and were unilocular (88.9%). Most lesions were managed with enucleation followed by application of Carnoy's solution (ferric chloride: 1g; chloroform: 3 mL; glacial acetic acid: 1 mL; ethyl alcohol 96%: 6 mL) and burring of the peripheral bone margin which resulted in the lowest recurrences (9.1%) besides resection. Significantly associated clinicopathological features with recurrences included patients who were male, large lesions (>90 mm), presence of root resorption, cortical perforation, mural subtype, and retention of associated teeth. In conclusion, decision making in the management of unicystic ameloblastoma should be based on the clinicopathological features and not be solely based on the histopathological subtype. Enucleation followed by application of Carnoy's solution and burring of the peripheral bone margin was demonstrated to be the least invasive method with an acceptable low recurrence rate. [ABSTRACT FROM AUTHOR]

Introduction: Ameloblastoma is an odontogenic tumour with high recurrence rate. The objective of the present study was to evaluate existing literature regarding clinical, radiographic, histopathologic features, treatment, and recurrence rate of ameloblastomas and compare it with features of recurrent ameloblastomas. Materials and methods: A systematic review was done based on the PRISMA statement. Search was performed in "Pubmed" database with search terminology "recurrent ameloblastoma", "ameloblastoma recurrence" for articles published between 2010 and 2020. Data were extracted from full‐text articles and discussed. Results: Out of 515 articles, 16 articles fulfilled the inclusion and exclusion criteria. Data was analysed in two sections. The first with 10 publications assessed features of ameloblastoma in general and their recurrence rate while the second section evaluated features of only recurrent ameloblastomas in 6 publications. There were 234 recurrences in 936 cases with recurrence rate of 23.50%. Male predominance was noted and mandible was commonly affected. Solid/multicystic ameloblastomas formed 74.5% of the tumours and unicystic formed 23.3%. The recurrence rate after conservative treatment was 64.9% and after radical treatment was 12%. Conclusions: The main factors for recurrence were multilocular ameloblastomas, follicular histopathology and conservative treatment. [ABSTRACT FROM AUTHOR]

Background: Hybrid odontogenic lesions combine histopathological characteristics of two or more odontogenic cysts and/or tumours. The aim of this study was to evaluate the available data on hybrid odontogenic lesions (HOL) and to analyse their epidemiological/clinical features and biological behaviour. Methods: An electronic search was done in January 2021 using multiple databases. Eligibility criteria encompassed publications with sufficient clinical and histological information to confirm the tumours' diagnoses. Results: A total of 147 articles were included in this study, comprising 203 cases. Calcifying odontogenic cyst associated with odontoma (COC/OD) (37/18.2%) was the most common HOL. Females were more affected with a mean age of 24.9 years. Lesions presented as asymptomatic swellings, with a mean evolution time of 8.2 months (0.3–96), and mean tumour size of 4.8 cm (0.3–7). Radiographic aspects frequently showed radiolucent (139/68.4%) and unilocular (52/25.6%) images with well‐defined limits (48/23.6%). The lesions mostly affected mandibular pre‐molars (69/34%) and mandibular molars (69/34%) regions. Enucleation (89/43.8%) and surgical excision (59/29%) were the most common treatment modalities. The mean follow‐up time was 33.8 months (0.5–216 months) and recurrences were observed in four cases (1.9%), all of which were central odontogenic fibroma associated with central giant cell granuloma (COF/CGCG). Conclusion: COC/OD is the most common HOL and recurrence is a rare event, being usually associated with the diagnosis of COF/CGCG. [ABSTRACT FROM AUTHOR]

Maxillary ameloblastoma is one of the rarest odontogenic epithelial tumors encountered, as 80% of ameloblastomas are seen within the mandible. Ameloblastoma is usually incidentally detected in the third to fourth decades of life, as most patients remain asymptomatic; yet some patients may complain of a slowly growing, painless swelling. We present a case of maxillary ameloblastoma with pulmonary metastasis along with a brief literature review. A 17-year-old male initially presented with painless right facial swelling, which, on examination, was non-tender, immobile, irregular, pink in color, with a high tendency to bleed, and located in the mucogingival sulcus with a size of around 3x2.5 cm. Following comprehensive radiological and histopathological evaluation, the diagnosis of ameloblastoma characterized by the coexistence of plexiform and follicular patterns was confirmed. The patient underwent a partial right maxillectomy with an obturator sealing the hard palate. Unfortunately, multiple local recurrences were identified afterward, and eventually, pulmonary metastasis was detected. Early and adequate surgical resection of the primary tumor is crucial to prevent further recurrences in patients with ameloblastoma. This could be achieved by providing a tight postoperative follow-up schedule while paying special attention to the lungs, neck, and other suspicious areas to detect metastasis as early as possible., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Al-Hakami et al.)

Background: Malignant odontogenic tumours (MOTs) arise either de novo from the tooth forming tissues, their developmental residues or from existing odontogenic epithelial or mesenchymal neoplasms in the jaws. Their management requires extensive surgery due to their infiltrative nature and risk of metastasis. There is a need to understand the clinical and pathological features of MOTs to inform both treatment algorithms and prognostication. This is an area of diagnostic pathology which presents substantial difficulties in diagnosis, compounded by inconsistent use of terminology. Thus, this systematic review aimed to describe the clinical and pathological features of MOTs with a view to consolidating the literature and defining problematic areas in diagnosis and classification.Methods: An electronic database search was conducted in Web of Science, PubMed/Medline, and Embase. Additionally, the grey literature and reference lists of selected papers searched for completeness. Nine hundred and sixty articles were initially identified. Following removal of duplicates and application of inclusion/exclusion criteria, 312 articles were included for qualitative analysis.Results: The 312 articles encompassed a total of 507 patients with most lesions located within the mandible (74.3%). The most common first histological diagnosis was ameloblastic carcinoma (25.7% of all diagnoses), but there is considerable variation in how and when various diagnostic terms are used, and several misdiagnoses were reported. An initial benign diagnosis was made in 24.7% of patients, followed by a later malignant diagnosis and in this sub-group, the most common benign first diagnosis was ameloblastoma (42.4%). Cervical lymph nodes were the most common site of metastasis (9.3% of patients). With respect to distant metastasis (DM), the lungs were the most common organ affected (11.2% of DM patients) with metastasising ameloblastoma the most commonly reported tumour which metastasised to the lungs. Overall, 26.8% of patients developed recurrence.Conclusion: Overall, the quality of the literature on MOTs is poor. This review of the literature has highlighted variations in diagnostic terms and criteria which has resulted in areas of confusion with potential for misdiagnosis. This consolidation of primary data has identified key areas for targeted research including further discussion on the malignant potential of ameloblastoma.

Odontogenic myxomas are rare clinical entities, comprising benign mesenchymal tumours arising from odontogenic cells. Bone involvement in considered a central odontogenic myxoma, whereas a peripheral odontogenic myxoma involves only the soft tissues. The latter is extremely rare, with only a few cases reported in the literature. In the present study, a peripheral odontogenic myxoma in the right mandibular area of a 35-year-old woman is reported, along with a thorough review of the literature.

Background: BRAF p.V600E is reported in up to 80% of ameloblastomas. Despite the high frequency, the presence of this mutation in different histopathological areas of the tumour has not been investigated. This information has an important role in the use of BRAF p.V600E assessment as an auxiliary tool in the differential diagnosis between unicystic ameloblastoma and other odontogenic cystic lesions, especially when only incisional biopsies are available. Therefore, the purpose of the present study was to investigate BRAF p.V600E heterogeneity in unicystic ameloblastoma. Methods: Five cases of ameloblastoma and two dentigerous cysts were analysed. The regions exhibiting different microscopic characteristics were selected from each ameloblastoma case and manually dissected. TaqMan allele‐specific qPCR or Sanger sequencing was performed to determine BRAF p.V600E status. Results: We screened the mutation in a small cohort of UA and no molecular heterogeneity was found. Four cases of ameloblastoma (80%) exhibited BRAF p.V600E in all different areas evaluated. One case did not harbour the mutation in any microscopic region analysed. The BRAF mutation was absent in the dentigerous cysts. Conclusion: Ameloblastomas appear to exhibit a homogeneous profile regarding the BRAF p.V600E no matter what histological feature is observed under light microscopy, suggesting that this molecular test may contribute to establish the correct diagnosis in cases microscopically resembling other odontogenic lesions. [ABSTRACT FROM AUTHOR]

Background: Malignant odontogenic tumours are extremely rare tumours occurring within the jaws. Our study was performed to determine the demographic and clinico-pathological features of malignant odontogenic tumours amongst a multi-ethnic Asian population. Methods: This was a retrospective cross-sectional study of malignant odontogenic tumours diagnosed at the Institute for Medical Research, Malaysia, from 2009 to 2019. All cases were independently reviewed and reclassified following the criteria set out in the latest edition of the World Health Organization 2017 reference text. Demographic and clinico-pathological data were recorded for each case. Results: Twenty-four cases of malignant odontogenic tumours were identified. The patients' age ranged from 16 to 79 years with the mean age at diagnosis being 50.8 years (SD = 16.18). There was a male predominance (66.7%) in this cohort of patients. The ethnic distribution appeared to reflect the Malaysian population with most cases seen amongst the Malay ethnic group (66.7%). Ameloblastic carcinoma was the most frequently diagnosed malignant odontogenic tumour (45.8%) and was also predominantly seen in males (90.9%). All patients with clear cell odontogenic carcinoma were females. There was no obvious sex predilection in primary odontogenic carcinoma not otherwise specified (NOS). The mandible (79.2%) was more frequently involved compared to the maxilla. Conclusions: Diagnosis and management of malignant odontogenic tumours are challenging due to the rarity of these tumours. Our study has elucidated the clinico-pathological features of malignant odontogenic tumours seen in a multi-ethnic Asian population. [ABSTRACT FROM AUTHOR]

Background: Although immunohistochemistry (IHC) along with molecular tests has been investigated in ameloblastoma for BRAF V600E detection, VE1 IHC has not been studied in odontogenic carcinomas (OCs) and benign mixed epithelial and mesenchymal odontogenic tumours (BMOTs). Here, we performed BRAF V600E mutation analysis, examined the expression pattern of VE1 IHC, and comparatively evaluated the performance of two VE1 antibodies in ameloblastomas, OCs and BMOTs. Methods: BRAF V600E detection was performed using Sanger sequencing in a total of 47 odontogenic tumours: 28 ameloblastomas, 6 OCs and 13 BMOTs. VE1 IHC was conducted using two different antibodies (IHC‐A and IHC‐V), and their performance was analysed by calculating the sensitivity and specificity compared with sequencing. Results: BRAF V600E mutations were identified in 24/28 (85.7%) ameloblastomas, 2/5 (40.0%) ameloblastic carcinomas (ACs), 3/7 (42.9%) ameloblastic fibromas and 1/2 (50.0%) ameloblastic fibro‐odontomas. In the presence of the mutation, VE1 showed diffuse cytoplasmic staining in ameloblastomas and ACs, whereas all BMOTs were negative for VE1. IHC‐A and IHC‐V yielded a sensitivity of 76.7% and 60.0%, respectively, although both antibodies showed 100% specificity. Conclusion: OCs and BMOTs have BRAF V600E mutations in common at lower frequencies than ameloblastoma. Diffuse VE1 cytoplasmic staining in AC suggests the utility of MAPK‐targeted therapy as selectively applied in ameloblastoma, and consistent VE1 false‐negative expression in BMOTs requires further investigation. Considering the high specificity but low sensitivity of VE1 IHC, molecular tests should be performed to determine the presence of BRAF V600E mutations in odontogenic tumours. [ABSTRACT FROM AUTHOR]

Odontogenic fibromyxoma typically presents as painless swelling in the jaw, and clinically, it grows slowly, becoming benign and asymptomatic. It causes the cortical plates to expand gradually, which leads to mobility and drifting of the teeth. Root resorption is also common. The tumor is locally aggressive in nature. It is also known to have a high recurrence rate. We present the case of a 30-year-old female patient who was diagnosed and treated for odontogenic fibromyxoma of the maxilla conservatively with enucleation. The radiograph showed a multilocular lesion, which can be confused with ameloblastoma, aneurysmal bone cyst, or odontogenic keratocyst. Hence, with proper clinical, radiographic, and histopathological examination, a correct diagnosis can be made and adequate treatment can be planned., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Hurkat et al.)

The extent to which load transfer in a diseased mandible with odontogenic tumour might influence the potential risk of pathological fracture has scarcely been investigated. The study sought to investigate the quantitative deviations in load transfer across healthy and cancer-affected (diseased) mandibles having odontogenic tumours. The effect of size of the tumours (small: 9 mm diameter, large: 19 mm diameter), and variation in bone mechanical (elastic) properties of the mandible on load transfer in cancer-affected mandibles during a mastication cycle have been investigated. Based on patient-specific computed tomography–scan datasets, detailed three-dimensional finite element models of healthy and diseased mandibles were developed. High stresses of 25–30 MPa and strains ∼700 µε were observed in the healthy mandible during the right molar bite. However, marginal deviations were observed in principal stress distributions in the diseased mandibles with small- and large-sized tumours, as compared to the healthy mandible. Maximum principal strains of ∼1474 µε were found in the body region adjacent to the symphysis region for small-sized tumour. Whereas for large-sized tumour, maximum strains of ∼2700 µε were observed in the right buccal regions. Reduction in Young's modulus due to different stages of odontogenic tumours had a localised effect on the principal stress distributions, but triggered an abrupt increase in the principal tensile strains. It appears that there is a potential risk of pathological fracture for large-sized odontogenic tumour, owing to high tensile stresses and strains. [ABSTRACT FROM AUTHOR]

Lesions arising from odontogenic tissues of the jaws vary from very common to very rare. Some, such as radicular cysts, form a routine part of the diagnostic workload for histopathologists who report specimens from the head and neck, but many other lesions are rarely seen and can cause significant diagnostic difficulty for the non-specialist. These issues are compounded by the vagaries of dental disease (and terminology used by dentists and oral surgeons) and issues in the interpretation of radiographic images, which can be crucial to making a correct diagnosis. In this review article, we will discuss a number of areas of diagnostic difficulty, largely based on the authors experience in receiving tertiary referrals. This will focus on practical advice to help avoid the pitfalls in the diagnosis of odontogenic lesions. [ABSTRACT FROM AUTHOR]

Background: Ameloblastoma is one of the most common benign odontogenic tumours in Nigeria. It is considered uncommon in children. Materials and methods: This is a retrospective study of pediatric patients with histopathological diagnosis of ameloblastoma seen over seven years at the Oral and Maxillofacial Surgery Department of the University of Nigeria Teaching Hospital, Enugu, Nigeria. Relevant information was retrieved from patients' records and data obtained were analysed using SPSS version 23, the chi-square test was used to compare qualitative variables, a p-value of <0.05 was considered as significant. Results: One hundred and thirty-six cases of ameloblastoma in all age groups were seen within the period. Thirty of the cases met the requirement. The mean age of the patients was 14.4 STD 2.03 (range from 10-17) years. Fourteen (46.7%) patients were male while 16 (53.3%) were female giving a ratio of 1:1.1. The duration of the lesion ranged from 3 months to 72 months (mean 15.07 months). Histologically, the follicular type (n=20, 66.7%) constitute the majority, while the clinical types were solid-multicystic (n=18, 60%) and unicystic (n=12, 40%). Enucleation was the treatment of choice in most (n=18, (60%)) of the patients. Conclusion: Ameloblastoma is relatively uncommon in children, especially those less than ten years of age. The solidmulticystic variety was the predominant type in the children studied. Most patients presented long after the onset of the tumour and enucleation with mechanical curettage produced satisfactory results in these patients. [ABSTRACT FROM AUTHOR]

Odontogenesis is a complex process, which involves the molecular interaction between the epithelium and ectomesenchyme called as epithelium mesenchymal interaction (EMI). Reduced enamel epithelium (REE) after tooth formation protects enamel from coming in contact with adjacent ectomesenchyme. Also, REE acts as a source of origin for odontogenic lesions, during the process of development of a lesion, disruption in REE may occur and lead to formed enamel coming in contact with adjacent ectomesenchyme leading to the formation of cementum like calcifications. REE may play a role in pathogenesis of hard tissue formation in odontogenic lesions.

INTRODUCTION: Odontogenic tumors originate from neoplastic transformation of the remnants of tooth forming apparatus. There are varying degrees of inductive interactions between odontogenic ectomesenchyme and epithelium during odontogenesis, leading to lesions that vary from benign to malignant. Malignant odontogenic tumours (MOTs) are very rare and are classified according embryonic tissue of origin. Recently, there has been a few changes to the classification of MOTs according to the World Health Organization's (WHO) classification in 2017. This study aims to evaluate and reclassify MOTs, using a multi-centre approach in some major tertiary dental hospitals in Nigeria. METHODS: this study reviewed the clinicopathological data on 63 cases of MOT diagnosed over 25 years in five major tertiary dental hospitals in Nigeria. All MOT cases were reclassified according to the recent revision to the 2017 WHO classification of odontogenic tumours. RESULTS: from a total of 10,446 biopsies of oral and jaw lesions seen at the 5 study centres over the 25-year study period, 2199 (21.05%) cases were found to be odontogenic tumours (OTs), of which 63 were MOT. MOTs constituted (0.60%) of the total biopsy cases and 2.86% of OTs. Odontogenic carcinomas presented with a mean age higher than odontogenic sarcomas. According to our 2017 WHO reclassification of MOTs, odontogenic carcinomas, ameloblastic carcinomas and primary intraosseous carcinomas were found to be the top three lesions, respectively. Carcinosarcomas were found to be extremely rare. CONCLUSION: using a multi-centre approach is a robust way to reduce diagnostic challenges associated with rare maxillofacial lesions such as MOTs.

Rationale: Peripheral odontogenic myxoma (POM) is a rare mesenchymal tumour and it is the first case report of POM involving orbital and zygoma region., Patient Concerns: A 16-year-old male presented with a painless, slow-growing swelling over his left infratemporal region., Diagnosis: The histopathological examination of the tumour was diagnosed as POM., Treatment: The patient was treated by surgical removal of tumour under general anaesthesia., Outcomes: The patient has been under follow-up for the past 2.5 years and there has been no recurrence., Take-Away Lessons: POM is a rare mesenchymal tumour. To our knowledge, this is only the second report of a POM of the infratemporal region and the first report of a myxoma, which extends into the zygomatic region and lateral wall of the orbit., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Annals of Maxillofacial Surgery.)