Search

Extra-axial chordomas are rare malignant tumours. As a subcategory of axial chordomas, these tumours arise outside the axial skeleton. This report describes the case of a 13-year-old male patient with a gingival mass in the left upper jaw, who was referred to Hannover Medical School with a preliminary diagnosis of a calcifying epithelial odontogenic tumour (CEOT). Pathological examination of the enucleated tumour led to the final diagnosis of a chordoma. Thereafter, a stepwise radical resection was performed with the aim of complete resection of the tumour with wide safety margins. The main tumour mass was found to be located on the maxillary gingiva, with focal infiltration into the maxillary bone. Following resection, reconstruction was performed with a free latissimus dorsi flap. Follow-up after 1 year revealed no signs of recurrence or metastasis. This case highlights that although extremely rare, extra-axial chordoma may occur at sites distant from the midline and as such must be included in the differential diagnosis of bone and soft tissue tumours in the maxillofacial region.

Primordial odontogenic tumour (POT) is a relatively newly described entity with well-defined clinicopathological features. Since its initial description in 2014, 22 cases of POT have been reported in the literature. Only five cases of POT have arisen in the maxilla. This article describes an additional patient with a POT of the maxilla and provides a review of the literature on POT.

The aim of this study was to review the literature on extra-osseous odontogenic keratocysts, and to present the best possible approach to these lesions.A comprehensive literature search was performed using the strategy: (keratocyst) and (soft tissue)). A total of 25 articles were included, 20 reported on extra-osseous odontogenic keratocysts in the soft tissues of the mouth and 17 presented as gingiva cysts.Almost all articles were published in the last 20 years and 16 even in the last 10 years. Extra-osseus odontogenic keratocysts are usually found in the cheek or present as gingiva cysts of adults. Muscle abutment of the cheek lesions is common but infiltration of muscles has also been reported.In almost none of the reported cases was a preoperative diagnosis available. Based on the clinical presentation and available laboratory tests it is suggested to always do an aspiration biopsy to ascertain the diagnosis preoperatively. This is particularly relevant for those who appear in the soft tissues of the mouth.

This study compared mandibular cortical thickness (CTh) and fractal dimension (FD) in patients with cemento-osseous dysplasia (COD) and controls, as measured with cone beam computed tomography.In total, 28 female patients with COD and 28 age-matched controls were selected retrospectively. Inferior cross-sectional CTh was measured at the symphysis (sCTh), anterior (aCTh), mental foramen (mfCTh), molar (mCTh), and posterior (pCTh) regions. The alternate measurement of mean CTh of the volume including buccal, lingual, and inferior cortices between the mental foramina (alternate CTh) was measured in ImageJ. FD was calculated in cortical and trabecular bone. Data were analyzed for significance of differences in CTh and FD between patient groups and for correlation of inferior and alternate CTh measurements.Inferior CTh values were lower overall in the patients with COD than in the controls (P = .01), specifically at sCTh, mCTh, and pCTh (P ≤ .042). Alternate CTh was also significantly lower in the COD group (P = .005). There was a significant correlation between inferior and alternate CTh measurements (r = 0.636, P.001). No significant differences were observed in cortical or trabecular FD between groups (P ≥ .072).Female patients with COD had significantly lower inferior and alternate CTh than healthy controls. Both groups had similar cortical and trabecular bone textures.

Odontogenic keratocyst (OKC) is known for its benign but aggressive clinical behaviour, and presents a challenge in its management due to high recurrence rate following surgical intervention. The sourcing of Carnoy's solution, the widely used adjunct in OKC treatment, has lately become difficult especially after its banning by the United States Food and Drugs Agency (FDA). This has generated interest in exploring alternative chemical agents such as 5-Fluorouracil (5-FU) and Modified Carnoy's solution (MCS). We conducted a systematic review and meta-analysis to assess the effectiveness of 5-FU as an adjunct following surgical intervention of OKC. A protocol was registered in PROSPERO prior to the literature search. All studies reporting the use of 5-FU in OKC treatment were included in the initial search of multiple literature databases. Of the 148 initially identified articles, three met the criteria for the final appraisal. The relevant data were extracted and a meta-analysis was undertaken in relation to recurrence rate and nerve paraesthesia. There were no recurrence observed in cases treated with 5-FU (n=56), and the incidence of nerve paraesthesia was 20% (none permanent). This systematic review has revealed early encouraging results for 5-FU as an adjunct, however a caution is recommended due to overall low quality of evidence related to individual studies. We present the cumulative evidence on the effectiveness of 5-FU in OKC treatment with discussion on its mechanism of action, safety profile, application protocol, and the implications for clinical practice.

Purpose Benign fibro-osseous lesions (BFOLs) are heterogeneous intraosseous disease processes sharing overlapping histopathologic features and demonstrate a wide range of biological behavior. The aim of this study is to highlight the importance of clinical and radiological findings for the definitive histopathologic diagnosis of benign fibro-osseous lesions of the jaws. Materials and Methods This is a cross-sectional retrospective study evaluating the three main groups of BFOLs: Cemento-osseous dysplasia, ossifying fibromas, and fibrous dysplasia. Previously diagnosed BFOL cases were searched for thoroughly from the archives of Istanbul University, Institute of Oncology, Department of Tumor Pathology in between 2005 and 2015. Clinical and radiological data of these cases were identified and recorded. The histopathologic features were reevaluated from the H&E-stained slides. Results A total of 276 BFOL cases were identified and reevaluated for the study. The most common BFOL type was cemento-osseous dysplasia (n = 135), followed by cemento-ossifying fibroma (n = 77), fibrous dysplasia (n = 53) and juvenile ossifying fibroma (n = 11). The female/male ratio was 3.4:1 with a strong predilection for the 4th decade (n = 102). The mandible (n = 209) was the predominantly affected jaw. Prominent osteoblastic rimming around the bony lesion was commonly observed for cemento-ossifying fibroma (n = 60/77), followed by cemento-osseous dysplasia (n = 23/135). Predominant ossification patterns showed some differences among the groups. The most common radiological feature was the mixed radiolucent/radiopaque internal structure. Conclusion Our results document various clinical, radiological and histopathologic findings of BFOLs. Even some histopathologic differences are observed, clinical and radiographic correlation is mandatory prior to the definitive histopathologic diagnosis of BFOLs for the prevention of possible misdiagnoses or inappropriate treatments.

Objectives Nevoid Basal Cell Carcinoma Syndrome (NBCS) is a rare genetic condition affecting multiple organs including the maxillofacial and dental region. The surgical removal of the odontogenic keratocystic tumors (OKT), the high rate of recurrence leads to a iatrogenic tooth loss requiring dental care. The aim of this study is therefore to describe the dental and orthodontic management, and to assess the impact of surgery on facial growth and oral development. Methods A retrospective study including 14 patients with GGS, followed at the Necker Enfants Malades Hospital. The study was carried out on the medical files and photographic records Results Patients developed on average 5.5 OKT (range: 1 to 11) and 1.7 recurrences (range:0 to 9) during the follow-up. The mean age at diagnosis of first OKT was 11.23 years (range: 6.75 to 16). KOTs were more frequently localized at the mandibular (30.9%) and maxillary molar level (25.1%). Forty-seven impacted teeth were extracted during the OKT removal. Eight patients out of 12 presented a class III skeletal relationship. The remaining ones had a skeletal class II associated with a hyperdivergent typology. Almost all patients had dental impactions with ectopic positions of the succedaneums tooth. At the inter-arch level, all patients needed orthodontic care, 3 patients did not begin their orthodontics. Orthodontic treatments began with an orthopedic phase followed by braces for the majority in 8 patients. Two patients had to undergo orthognathic surgery. Impacted teeth were treated by traction or extraction with further rehabilitation. Conclusion The objective is not to simply compensate the iatrogenic hypodontia generated by the surgical procedure but to take into consideration the maxillofacial phenotype, skeletal characteristics and numerous intra- and inter-arch dental anomalies for a healthy oral management.

The aim of this study was to evaluate the benign paediatric jaw lesions based on the 2017 World Health Organization (WHO) classification. Demographic data, symptoms, radiographic findings, location, size, histopathologic diagnosis, treatment modalities, and outcomes were analysed retrospectively. Recurrence incidence, time to recur, and follow-up time were also evaluated. One hundred seven lesions were diagnosed in 100 patients (44 female, 56 male). The mean follow-up time was 56.6 ± 45.7 months. The mean age was 12. 9 ± 3.9 years and the majority of lesions were found in the permanent dentition group (p = 0.045). There were 73 patients with odontogenic cysts, followed by 16 patients with odontogenic tumors, and 11 patients with non-odontogenic tumors. Eighty seven lesions (81%) were radiolucent and 93 lesions (86%) were well-circumscribed. The majority of the patients (n = 96) were treated by enucleation. Recurrence was seen in 3 patients. The most notable difference between the results of the present study and the results of the study conducted in medical institutions was the distributions of jaw lesions. Within the limitations of the study it seems that a conservative treatment of benign jaw lesions should be preferred in the paediatric population because this treatment yields acceptable results.

Objectives The objective of this study was to demonstrate the clinical, radiologic, and histologic features of orthokeratinized odontogenic cyst (OOC); determine the characteristics of multiple OOCs; and present rare but significant manifestations of OOC. Study Design A clinical, radiologic, and histopathologic study of 65 primary and 2 recurrent OOC cases was performed retrospectively along with a comprehensive literature review. Results OOCs shared similar radiologic findings with odontogenic keratocyst, yet some showed features that have not been previously described: root resorption and radiopaque foci. Histologic review revealed a unique histiocytic lining and some findings suggestive of the multipotentiality of the odontogenic epithelium. The analysis of patients with multiple OOCs demonstrated that multiple OOCs occurred synchronously with a marked predilection for young male adults. Two unusual cases were also identified: an OOC combined with a BRAFV600E ameloblastoma and a recurrent OOC with malignant transformation. Conclusions This largest series presents previously unreported radiographic and histopathologic features that can be seen in OOC. Multiple OOCs have clinical characteristics distinct from those of solitary cases. The first reported OOC associated with ameloblastoma suggests the involvement of oncogenic mutations in odontogenic tumorigenesis. Although OOC shows a low recurrence rate, the possibility of malignant transformation of recurrent OOCs should be emphasized.

Abstract introduction Odontogenic Keratocysts are benign, developmental, locally aggressive odontogenic cystic lesions with a high risk of recurrence. As such, the most effective treatment modalities remain controversial. The mainstay of treatment remains enucleation with or without decompression. The use of adjunctive therapies is widely reported. Aims To review our experience of OKCs and therefore identify the treatment modality, if any single one, with the lowest rate of recurrence. We also aimed to identify any common themes linking those patients experiencing cystic recurrence. Methods Data was collected on 50 patients treated at UHCW NHS Trust over a 14 year period (2005-2018) via an anonymised database. Surgical pathways were analysed, including details of the location of the cysts and the use of adjunctive therapies, namely; mechanical debridement, cryotherapy, and the use of Carnoy’s solution. Results 56 keratocysts, both primary (91%, n = 51) and recurrent (9%, n = 5) were included. 6% of patients had a pre-existing diagnosis of Gorlin-Goltz Syndrome (n = 3). Enucleation was performed in an approximately 3:1 ratio to decompression with secondary enucleation (n = 41:15). 27% patients had adjunctive therapies (n = 15). There was a 12% recurrence rate (n = 6) found only within the group of primary cysts that had been enucleated alone. Notably, there were no recurrences in those cysts that had undergone adjunctive therapy. None of the cysts that underwent initial decompression or marsupialisation recurred. Following surgical intervention, no tertiary recurrent cysts were detected post-operatively. Conclusions This study demonstrates the advantage of establishing a correct diagnosis prior to definitive treatment. Initial decompression in selected patients followed by enucleation, along with adjunctive therapies show a benefit in reducing recurrences. However, in the absence of high-quality evidence for the most effective management of Odontogenic Keratocysts, finding a common approach will remain controversial.

In this study, we aimed to systematically review and critically appraise the available literature concerning the effectiveness of marsupialisation and decompression on the reduction of cystic jaw lesions. The 'Preferred Reporting Items for Systematic Reviews and Meta-Analysis' guidelines were followed and the study protocol was registered at the 'International Prospective Register of Systematic Reviews' (CRD42019116099). Six main databases were searched: Embase, LILACS, PubMed, Scopus, The Cochrane Library, and Web of Science. Searches were complemented with three grey literature sources: Google Scholar, ProQuest, and Open Grey. Any reduction measures, compared with preoperative status or other procedures, were considered. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tool. Thirty-one studies were included, of which five were judged with low, 24 with moderate, and two with high risk of bias. Considering surgical approach, 20 studies assessed the decompression and 11 the marsupialisation technique. Most studies considered these techniques as preliminary treatments, followed by enucleation. From 1088 lesions found, most were odontogenic keratocysts (33.8%), followed by unicystic ameloblastomas (21.0%), dentigerous cysts (20.6%), and radicular cysts (8.4%). Large lesions and younger individuals frequently presented more favourable responses to treatment and anatomical location was not associated with lesion reduction overall. The intervention duration generally ranged between one to two years. In conclusion, marsupialisation and decompression were mostly considered as preliminary treatments, followed by enucleation. Lesion reduction was generally considered insufficient for these techniques to be used as definitive therapies, although benefits concerning the diminished invasiveness of the secondary surgery were often proposed.

The odontogenic keratocyst (OKC) is a potentially aggressive odontogenic lesion and there is an ongoing debate regarding its biological behavior and classification. The present systematic review aims to assess the expression of the p53 protein in the odontogenic keratocyst in comparison to the dentigerous cyst and ameloblastoma. We searched MEDLINE, Web of Science and Scopus for immunohistochemical studies reporting OKC's, dentigerous cysts and solid/multicystic ameloblastomas. The Risk Difference between the lesions expressing the p53 was the effect measure and a P value

Purpose Carnoy's solution (CS), the gold standard for adjunctive chemical cautery in treatment of odontogenic keratocysts (OKCs), has been banned for 7 years, leading to substitution with the non-chloroform containing modified Carnoy's solution (MC) without data to support its effectiveness. We performed this study to compare the earlier data with CS to the more current outcomes with MC. Methods A retrospective cohort study was conducted on patients diagnosed with OKC and treated by a single surgeon (GHB) with enucleation and curettage (EC), peripheral ostectomy, and application of CS or MC. The primary predictor variables were use of CS or MC. The primary outcome variables were recurrence (yes vs. no) and time to recurrence. Secondary variables included demographics, anatomic location, and whether teeth adjacent to the lesion were extracted. Statistical analyses included chi-squared test/Fisher's exact test, Wilcoxon rank sum test, and Kaplan-Meier curves. Results 77 patients, 36 patients in the CS group and 41 in the MC group, met inclusion criteria, including at least 1 year of follow-up time. Characteristics of the groups were similar: median age 41.5 and 46, 61% and 71% male gender, 81% and 90% posterior, and 64% and 50% mandibular lesions, respectively. Overall recurrence was similar, 14.29%, with 5 (13.9%) recurrences in the CS group and 6 (14.6%) in the MC group (P = 0.92). Median time to recurrence was 24 months for both groups. Preserving adjacent teeth was associated with a significant increase in recurrence (P = 0.0036). Conclusion Based on this comparison of retrospective outcome data, we found no significant difference in recurrence rate or distribution of time to recurrence between OKCs treated with CS or MC. Aggressiveness of surgical technique is likely a predictive factor in recurrence rate. Future studies should focus on prospective studies and continuing follow-up of the MC group.

Objective The aim of this study was to report the clinicopathologic features of 105 new cases of adenomatoid odontogenic tumor (AOT) from Brazil, Guatemala, Mexico, and South Africa. Study Design Clinical and radiographic data were collected from records of 5 oral pathology laboratories, and all cases were microscopically reviewed. Results This series of cases included 36 (34.2%) from South Africa; 33 (31.4%) from Brazil; 23 (21.9%) from Mexico; and 13 (12.3%) from Guatemala. Seventy-two patients (68.5%) were females and 33 patients (31.4%) were males, with an average age of 19.2 years. The tumors predominantly affected the anterior maxilla (48.5%), followed by the anterior mandible (29.5%); posterior mandible (15.2%); and posterior maxilla (6.6%). Sixty-three tumors (63.6%) were follicular, 34 (34.3%) were extrafollicular, and 2 (2%) were peripheral. In most cases, the tumors caused considerable cortical expansion (average size 3.4 cm). Microscopically, most cases showed rosette-like and duct-like structures. Conclusions This is one of the largest case series of AOTs reported in the literature and the first multicenter study involving populations from Latin America and South Africa. In a fifth of the present cases, the posterior regions of the gnathic bones were affected and the tumors demonstrated larger sizes compared with cases occurring in other populations.

The solid variant of odontogenic keratocyst (SOKC) is an extremely rare odontogenic lesion, which remains poorly defined even in the 2017 World Health Organization odontogenic tumour classification. It is difficult to distinguish between SOKC and so called keratoameloblastoma (KAB), both rare lesions that have similarities in clinical, histological and biological characteristics. Here, we report clinicopathological data and results of molecular analysis of nine cases with a literature review. First, they were compared to previously reported cases of SOKC and/or KAB, and many overlaps were found in clinical and pathological characteristics. Second, we performed PCR analysis for BRAF V600E mutation. Although ameloblastoma-like epithelia were often encountered, none exhibited BRAF V600E mutation, which has been reported to occur frequently in ameloblastomas but not in odontogenic keratocysts (OKCs). One of two cases of SOKC in the present series from which fresh frozen tissue specimens were available was found to harbour PTCH1 mutations, indicating that these were more likely to be a subtype of OKC. Moreover, we also examined the differences between SOKC and primary intraosseous carcinoma (PIOC) with regard to the expression of cytokeratins (pan-CK, CK5/6, CK7, CK8/18, CK10, CK14 and CK19), p53 and Ki-67. The proportions of p53-and Ki-67-positive cells were significantly higher in PIOC than in SOKC. These findings suggest that immunostaining for p53 and Ki-67 would be useful to differentiate between SOKC and PIOC. We also conducted a review of SOKC and KAB cases reported in the English language literature.

Objective The aim of this study was to report the clinicopathologic features of 62 cases of central odontogenic fibroma (COdF). Study Design Clinical and radiographic data were collected from the records of 13 oral pathology laboratories. All cases were microscopically reviewed, considering the current World Health Organization classification of tumors and were classified according to histopathologic features. Results There were 43 females and 19 males (average age 33.9 years; range 8–63 years). Clinically, COdF lesions appeared as asymptomatic swellings, occurring similarly in the maxilla (n = 33) and the mandible (n = 29); 9 cases exhibited palatal depression. Imaging revealed well-defined, interradicular unilocular (n = 27), and multilocular (n = 12) radiolucencies, with displacement of contiguous teeth (55%) and root resorption (46.4%). Microscopically, classic features of epithelial-rich (n = 33), amyloid (n = 10), associated giant cell lesion (n = 7), ossifying (n = 6), epithelial-poor (n = 3), and granular cell (n = 3) variants were seen. Langerhans cells were highlighted by CD1a staining in 17 cases. Most patients underwent conservative surgical treatments, with 1 patient experiencing recurrence. Conclusions To the best of our knowledge, this study represents the largest clinicopathologic study of COdF. Most cases appeared as locally aggressive lesions located in tooth-bearing areas in middle-aged women. Inactive-appearing odontogenic epithelium is usually observed within a fibrous/fibromyxoid stroma, occasionally exhibiting amyloid deposits, multinucleated giant cells, or granular cells.

Ameloblastoma is a benign odontogenic tumor which undergoes malignant transformation to ameloblastic carcinoma. However, rarely it metastasizes without undergoing cytological malignant changes, an entity referred to as Metastasizing Ameloblastoma (MA). Through this study, we aimed to review cases of MA reported since 2000 to explore the impact of clinico-demographic variables on its prognosis. Based on PRISMA guidelines, a review of relevant literature from PubMed/Medline, Science Direct and Cochrane database was performed from January 2000 to March 2019. A total of 65 cases were considered for further evaluation as per predefined inclusion and exclusion criteria. Results showed that lungs followed by lymph nodes were the most common sites for benign metastatic deposits. Multiple recurrences and inadequate surgical removal increase the probability of distant metastatic spread. Despite having benign cytological features, tumor recurrence and metastasis were associated with an unfavorable clinical outcome in MA.

Purpose Squamous odontogenic tumor (SOT) is a rare, benign, locally infiltrative odontogenic tumor of the gnathic bones. It is composed of islands of bland, well-differentiated squamous epithelium of varying shape and size. Because of histologic overlap, SOT has often been overdiagnosed as ameloblastoma and squamous cell carcinoma. It thus becomes important to understand the clinical, radiologic, histopathologic, and treatment characteristics of this tumor. Materials and Methods Using the PubMed and Google Scholar databases, we searched for reported cases of SOT published in the English-language literature. We were able to retrieve 49 acceptable cases and perform a comprehensive literature review of the intraosseous SOTs, with emphasis on their clinical, radiographic, and pathologic characteristics, as well as treatment strategies. In addition, we present an additional case of SOT affecting the posterior mandible in a 44-year-old female patient. Results The tumor in the posterior mandible in our patient was accompanied by acute pain and treated by enucleation. Histopathologic evaluation showed variably sized islands of benign squamous epithelium scattered in a fibrous stroma, consistent with the diagnosis of an SOT. Uneventful healing was noted at the 1-month postoperative appointment. However, the patient was lost to long-term follow-up. Our literature review showed that the average age at the time of diagnosis of SOT is 34.2 years. Men and women are equally affected, and the tumor does not show a predilection for either jaw bone. The most common locations are the anterior maxilla and posterior mandible. Most SOTs are treated conservatively by enucleation or curettage, whereas aggressive or recurrent tumors require radical resection. Conclusions Careful evaluation of the excised specimen, with immunohistochemical investigations, may prove rewarding in differentiating an SOT from other odontogenic neoplasms and thus minimize the patient's chances of undergoing an unnecessary aggressive intervention.

The molecular pathogenesis of mixed odontogenic tumors has not been established, and understanding their genetic basis could refine their classification and help define molecular markers for diagnostic purposes. Potentially pathogenic mutations in the component tissues of 28 cases of mixed odontogenic tumors were assessed. Laser capture microdissected tissue from 10 ameloblastic fibromas (AF), 4 ameloblastic fibrodentinomas (AFD), 6 ameloblastic fibro-odontomas (AFO), 3 ameloblastic fibrosarcomas (AFS), and 5 odontomas (OD) were screened by next-generation sequencing and results confirmed by TaqMan allele-specific quantitative PCR. BRAF p.V600E mutation in the mesenchymal component was shown in 4 of 10 AF (40%), 2 of 4 AFD (50%), 2 of 6 AFO (33%), and 2 of 3 AFS (67%), whereas all 5 OD were wild type for BRAF p.V600E. Mutation in the epithelial component was only observed in one AF and one AFO. One AFS contained an area of benign AF, and the mesenchymal component of both (AFS and AF) contained BRAF p.V600E, supporting the concept of malignant progression from a benign AF precursor. KDR, TP53, KIT, and PIK3CA single-nucleotide polymorphisms are reported. In conclusion, AF, AFD, AFO, and AFS show BRAF p.V600E in their mesenchymal component, unlike OD, which are BRAF wild type, suggesting that at least a subset of AF, AFD, and AFO are molecularly distinct from OD, and may represent distinct entities and be neoplastic.

The aims of this study were to describe the frequency of odontogenic tumours (OT) based on the World Health Organization’s (WHO) 4th edition of Head and Neck Tumours in Turkey, to compare the results with other regions and to assess the frequency changes of OT worldwide after the new WHO classification. OT were selected from the pathology department’s files between 1971-2018. In a total of 1231 OT, 1215 (98.7%) were benign, whereas malignant OT were only 16 cases (1.3%). The three most common tumours were ameloblastoma (n = 366, 29.7%), odontoma (n = 335, 27.2% both complex and compound types), and odontogenic myxoma (n = 190, 15.4%), respectively. After the 2017 classification, the decrease of OT frequency was found among 20%-42% in the selected epidemiological series because of re-classification of some lesions. The pattern of incidence in the Turkish population is similar to that in other populations. However, there are some differences in the frequency of the tumour types. It is obvious that the relative frequency of odontogenic tumours worldwide will change based on the new classification. It should be kept in mind that this is not a real decrease of OT cases. These marked changes in the frequency and prevalence of OT is just related to reclassification of some entities.

Decompression of the odontogenic keratocyst has been a long-standing treatment modality in the armamentarium of oral-maxillofacial surgeons. Many different types of effective decompression tubes have been described in the literature. They reduce the size of the cystic lesion by decreasing the intraluminal pressure, induce histologic structural changes in the epithelial lining of the cyst, and allow for bone deposition to occur from the periphery of the cystic cavity. However, many of these have pitfalls including tube dislodgement, traumatization of the oral mucosa, and mucosal overgrowth. We describe a novel technique using an indwelling voice prosthesis (Inhealth Technologies, Carpinteria, CA) to decompress odontogenic keratocysts. We found that our method provides effective decompression using appropriate-length prostheses fit to the cyst dimensions. It provides improved comfort in patients, with less mucosal irritation or overgrowth, improved ease of irrigation, and improved retention that often does not require sutures.

Odontogenic cysts and tumors are heterogeneous lesions, originating from elements or remnants of the odontogenic apparatus. Although the majority of these lesions are benign and never undergo malignant transformation, rare malignant tumors may arise de novo or from benign precursors. The molecular basis of these lesions is still poorly understood. This article summarizes and discusses studies using small, medium, and large-scale and/or "-omic" techniques to describe the molecular characteristics of benign and malignant odontogenic lesions and briefly debates strategies to increase the use of "-omic" and multi-omic approaches or integrative analyses in the research of these lesions. A comprehensive understanding of the molecular aspects of odontogenic lesions by using large-scale approaches will enable us to refine the classification of this heterogeneous group of disorders and provide more accurate biomarkers for precise diagnosis, prognosis, and development of molecular tools in the management of patients with these conditions.

Odontogenic tumors are a group of neoplastic growths that originate from the tissues responsible for tooth formation and the periodontal apparatus of the jaw. Odontogenic tumors usually present as radiolucent defect, which makes diagnosis somewhat confusing while differentiating them from cysts. Although cystic lesions are surrounded by sclerotic borders, few odontogenic tumors share similar features. This article reviews clinical concepts of several odontogenic tumors that occur in the proximity or in association with teeth and not merely focusing on relatively common conditions.

Objectives Peripheral odontogenic fibroma (POF) is a relatively rare odontogenic tumor of the gingiva. Although its histological differential diagnosis from fibrous epulis (FE) is important, no study has reported the differences in their expression of immunohistochemical markers. Here, we compared the expression of tumor markers that are frequently used for the differential diagnosis of fibroproliferative lesions between POF and FE. Methods Forty cases were selected, including 20 POF and 20 FE cases. CD34, B cell lymphoma (Bcl)-2, and Ki-67 were used as markers for immunohistochemical examination. The positive cell ratio was calculated, and Mann-Whitney U test was performed for statistical analysis. Results POF and FE were negative for CD34 expression but showed Bcl-2 and Ki-67 expression. The ratio of Bcl-2- and Ki-67-positive cells was significantly higher in POF than in FE (p Conclusions POF is CD34 negative, and Bcl-2 and Ki-67 positive-cell ratio differs between POF and FE, suggesting that these proteins may serve as immunohistochemical markers for the differential diagnosis of POF.

Ameloblastic carcinoma is a rare odontogenic neoplasm that demonstrates the histologic characteristics of ameloblastoma, accompanied by the cytologic features of malignancy. The spindle-cell variant of ameloblastic carcinoma (SCAC) is exceptionally rare, with a total of 10 cases having been reported in the literature to date. Histologically, a prominent sarcomatoid cell population appears to originate from the epithelial (ameloblastic) component. Like conventional ameloblastic carcinoma, most cases of SCAC occur in individuals older than 40 years of age. Here, 3 additional cases of SCAC are reported, 2 of which occurred in young individuals. Diagnostic criteria to aid in the identification of SCAC are proposed. Finally, histologic and immunohistochemical evidence supporting the occurrence of epithelial-mesenchymal transition in SCAC is presented.

This epidemiological study was designed to find out the incidence and factors associated with the occurrence of intraosseous lesions diagnosed at a Reference Centre in Brazil. We included all patients diagnosed with intraosseous lesions (cyst, tumour, bone-associated lesion, and periapical disease) during the period 2006-2017, and analysed the association between some sociodemographic and clinical variables and the types of lesion. There was a total of 290 intraosseous lesions, the most common being odontogenic cysts. There was a significant association between age and odontogenic tumours (p=0.001). In relation to the histopathological diagnosis, root cysts were the most common (n=57), followed by dentigerous cysts (n=26). The lesions studied were seen most often in women between the second and fourth decades of life, odontogenic cysts being the most common type found. We know of few publications of similar epidemiological work, either in Brazil or in the rest of the world, so we suggest that more such studies are made.

The aim of this study was to analyze and compare the immunoexpressions of Regγ, Wnt-1, and β-catenin in ameloblastomas, adenomatoid odontogenic tumors (AOTs), and odontogenic keratocysts (OKCs).Thirty solid ameloblastomas, 20 AOTs, and 30 OKCs were selected for analysis of the immunoexpression of Regγ, Wnt-1, and β-catenin. Each case was semiquantitatively evaluated in the epithelial component and in their different cellular compartments (membrane, cytoplasm, and nucleus).Ameloblastomas displayed higher cytoplasmic and nuclear Regγ expression compared with AOTs and OKCs, as well as higher membrane and cytoplasmic Wnt-1 expression (P.05). β-catenin membrane expression was higher in OKCs compared with ameloblastomas and AOTs (P.05). Nuclear β-catenin expression was higher in ameloblastomas and AOTs than in OKCs (P.05). Cytoplasmic and nuclear Regγ expression in AOTs were positively correlated with nuclear β-catenin expression (P.05).The marked expressions of Regγ, Wnt-1, and β-catenin suggest the participation of these proteins in the pathogenesis of the studied lesions. The greater expressions of Regγ, Wnt-1, and nuclear β-catenin in ameloblastomas may be related to their more aggressive behavior. Pro-tumor effects of nuclear β-catenin may be counterbalanced by inhibitory pathways in AOTs, justifying their low aggressiveness.

Although rare, ameloblastic carcinoma (AC) is one of the most common malignant tumors occurring in the odontogenic epithelium. Evidenced-based medical guidelines for AC are not established because AC is a rare type of cancer. However, surgery for AC is the primary initial treatment modality. A few reports suggest that radiotherapy (RTx) is effective for AC; however, the tumor is generally considered to be radioresistant. Furthermore, if RTx is performed for AC, osteonecrosis may occur because most of the ACs arise from the jaw. Here, we report a case of an older patient with maxillary AC who had underlying medical problems and who received conventional RTx with good outcomes. Ten years after the treatment, no major adverse event accompanying irradiation, local recurrence, or metastasis was observed. We discuss the therapeutic effect and usefulness of RTx on AC. As indicated by our findings, RTx for AC may represent a definitive treatment strategy for patients with poor general conditions or those with tumors that cannot be resected completely.

Objectives Odontogenic tumors (ODTs) are a heterogeneous group of lesions derived from elements of tooth-forming tissues. No detailed data on the incidence of odontogenic tumors in the United Kingdom have been published. The aim of this study was to retrospectively describe the range and incidence of odontogenic tumors from 1992 to 2016 in a single specialist unit and to compare this population with others. Study Design By using the Oral and Maxillofacial Pathology database, Sheffield (UK), we included both local and referred consultation cases. A proportion of diagnoses were reclassified in accordance with the 2017 World Health Organization classification. Results In total, 559 odontogenic tumors were diagnosed. Overall, the most common lesions were ameloblastoma (196 [33.8%]), odontoma (148 [25.5%]), and odontogenic myxoma (37 [6.3%]), but this varied between local and referral case populations, with odontomas being most common in the local population (43%). The sites affected and the gender and age of patients were similar to other Western populations. Malignant ODTs comprised 33 cases (5.7%), of which 9 (27.3%) were ameloblastic carcinoma. The majority of the malignant ODTs comprised referral cases. Conclusions Here, we present the first detailed data on ODTs within a UK population, and the pattern of incidence from the local population is similar to other Western populations. The exceptional rarity of malignant ODTs emphasizes the need for specialist centers for their treatment to gain diagnostic experience.

OBJECTIVES: Ameloblastoma is an aggressive odontogenic jaw neoplasm. Its unlimited growth confers high potential for malignant transformation and recurrence. It is unclear why ameloblastoma is highly recurrent despite surgical resection with a wide margin of normal tissue. While canonical autophagy can be used to degrade and eliminate damaged cellular components, it is also a protective mechanism that provides energy and vital metabolites for cell survival. We used ameloblastoma-derived cells to test the hypothesis that autophagic processes play a role in survival and reactivation of ameloblastoma. METHODS: Primary epithelial (EP-AMCs) and mesenchymal (MS-AMCs) ameloblastoma-derived cells were established from tissue samples of solid multicystic ameloblastoma. Clonogenic capacity and basal autophagic capacity were assessed in ameloblastoma-derived cells relative to human odontoma-derived cells (HODCs) and maxilla-mesenchymal stem cells (MX-MSCs). Ability of ameloblastoma-derived cells to survive and form new ameloblastoma was assessed in mouse tumor xenografts. RESULTS: EP-AMCs were highly clonogenic (p < 0.0001) and demonstrated enhanced basal levels of autophagic proteins microtubule-associated protein 1-light chain 3 (LC3) (p

Highlights • A 26-year-old male presented asymptomatic swelling on the right side of the face. • The two biopsies (incisional and excisional) were compatible with calcifying epithelial odontogenic tumor (CEOT). • This CEOT was treated with enucleation without safety margins and showed no signs of recurrence in five years of follow-up., Introduction The calcifying epithelial odontogenic tumor (CEOT), also known as Pindborg tumor, is a locally invasive benign neoplasm. Histogenesis is controversial. Presentation of case A 26-year-old male presented asymptomatic swelling on the right side of the face, with approximately six months of evolution. At intraoral examination, a hard nodule localized in the right posterior region of the maxilla, measuring approximately 5.0 x 3.0 cm was observed. The computed tomography images showed hypodense lesion with points of calcification associated with two non-erupted teeth. We suspect of odontogenic lesions. The final diagnosis of CEOT was established based on the histopathological aspects. Discussion This tumor is more frequent in adult men, usually develops in the posterior region of the mandible and may present clinical-pathological similarities with others odontogenic lesions. The radiological aspects observed in the CEOT are variable and depend on the time of evolution of the tumor. The histopathological examination is mandatory to establish the final diagnosis. Conclusion Our case was treated with simple enucleation without signs of recurrence in five years of follow-up. Further studies are needed to understand the aetiology and the biological behaviour of this tumor.

Background/purpose: The classification and treatment of odontogenic keratocyst (OKC) are controversial. The objective of this study was to present the efficiency of decompression followed by enucleation by clinical and histomorphometric evaluation for the treatment of OKC. Materials and methods: Thirty four OKCs of 27 patients who underwent decompression followed by enucleation were included in this study. Clinical and histomorphometric analysis were performed. Results: The average decreasing rate was 59% in maximum diameter, 66% in the amount of the volume for the average of period of the decompression was 9.8 months. The mean of increasing rate of the thickness of the epithelial lining was 921.16%. There were no recurrences for a mean follow-up period of 5.8 years. The thin and friable cyst wall of the OKC was changed to thickened, hard type. Conclusion: The decompression was found to be effective and reliable as a treatment of the OKC to decrease the recurrence tendency, even for Gorlin-Goltz syndrome. Keywords: Epithelial thickness, Jaw cysts, Keratocysts, Odontogenic tumors

Objective The aim of this study was to clarify the clinicopathologic features of central odontogenic fibroma (OF), especially the amyloid variant, and to discuss its association with the Langerhans cell variant of calcifying epithelial odontogenic tumor (CEOT). Study Design The clinicopathologic features and immunophenotypes of 17 OFs, including 6 amyloid variants, were analyzed. The Langerhans cell variant of CEOT is reviewed, and its relationship with OF is discussed. Results Most OFs (13 of 17) were located at the anterior region of the jaws, often with root resorption. The amyloid variant exhibited the typical clinicopathologic features of OFs, characterized by dispersed small epithelial nests embedded in a fibrous stroma. Immunohistochemically, the epithelial component in all central OFs, including the amyloid variants, exhibited dispersed staining for CK10/13 but was negative for CK7 and CK8/18. Langerhans cells were positive for S-100 and Langerin in the epithelium of OFs, including the amyloid variants. Conclusions The amyloid variant of OF is a rare benign tumor exhibiting the typical clinicopathologic features of conventional OFs and should not be diagnosed as CEOT even in the presence of amyloid deposits. Previously reported cases described as “Langerhans cell variant of CEOT” should be classified as the “amyloid variant of OF,” given that it shares features more in common with OFs than with CEOTs.

Introduction The surgical removal of an intraoral tumor and preventing intraoral wound dehiscence are constant challenges faced by surgeons today. Hyperbaric oxygen therapy (HBOT), the inhalation of 100% oxygen at a greater atmospheric pressure, is often used in cases of wounds to induce a faster wound healing process, alongside other treatment modalities. We report a rare case of squamous odontogenic tumor (SOT) treated with HBOT after being surgically removed to foster an accelerated wound recovery. Case presentation A 39-year-old Asian male presented with an intraoral 3 × 4 cm tumor, accompanied by acute pain on the maxillary region. Biopsy results showed a solid, brown parenchyma with islands of mature squamous epithelial cells, confirming the diagnosis of an SOT. An intraoral surgical approach was performed to remove the tumor. The patient was then treated with prophylactic antibiotics and 5 consecutive, daily sessions of HBOT at 2.0 ATA as an adjuvant therapy. No further complaints and no abnormalities were found at the 2-week follow-up evaluation. Discussion In our case of SOT, HBOT plays a role to inhibiting the bacterial growth which could lead to post-operative wound infections. A number of studies have incorporated HBOT as an adjuvant therapy for post-operative intra oral wounds which has resulted in minimal wound complications. Conclusion The use of HBOT as an adjunctive therapy in managing possible wound complications after the resection of an intraoral tumor enables a faster angiogenesis process, reduces tissue hypoxia and minimizes the risk of post-operative wound infections; hence fostering the wound healing process., Highlights • Squamous odontogenic tumors (SOT) are very rare tumors. • SOTs are local infiltrating lesion described as aggressive, odontogenic, and epithelial. • HBOT can be used as supportive therapy in SOT. • Hyperbaric oxygen therapy (HBOT) can accelerate wound healing and minimize the possibility of postoperative infection.

Objective Odontogenic myxoma (OM) is a rare benign tumor that is frequently nonencapsulated and invades the surrounding bone, resulting in a high risk of recurrence. However, the optimal surgical technique and appropriate surgical margin remains controversial. Here, we report our clinical investigation of 12 patients with OM diagnosed histopathologically. Study Design We retrospectively reviewed the records of 12 patients treated at our institution. Osteotomy or bone shaving with enucleation was generally performed with 5-mm bony margins from the radiologic extent of the tumor. Results One half of the cases occurred in the maxilla and the other half in the mandible. Treatment for maxillary OM was enucleation in 2 patients and maxillectomy in 4 patients. Treatment for mandibular OM was enucleation with shaving of the surrounding bone in 1 patient and segmental mandibulectomy in 5 patients. Radiographs of surgical specimen removed by segmental mandibulectomy indicated that the mean distance between the tumor and the margin was 5.4 (range 3.4–7.0) mm. Tumor recurrence was noted in 1 patient who had undergone enucleation alone. Conclusion The 1-cm surgical margin for OM, as reported conventionally, might not be necessary. A prospective study is needed to determine the appropriate surgical margin for OM.

Purpose To integrate the available data published on central odontogenic fibroma (COF) into a comprehensive analysis of its clinical/radiologic/histological features. Methods An electronic search was undertaken in September 2017. Eligibility criteria included publications reporting cases of COF having enough clinical, radiological and histological information to confirm the diagnosis. Demographic data, lesion site and size, treatment approach, and recurrence were analysed. The cases included in the analysis presented follow-up time. Concerning recurrence analysis, tumour location, cortical bone perforation, lesion locularity, radiopacities, lesions associated with a tooth, tooth displacement, histological type and treatment used were evaluated. Results Eighty-three publications reporting 173 COFs were included. Lesions were slightly more prevalent in men than women (M: F – 1.13: 1); mean age was 31.6 years, with the highest prevalence in the second decade of life. Lesions were more prevalent in the posterior mandible. The difference in recurrence rate (when information about recurrence was provided) presented a statistically significant result for COF for location, cortical bone perforation and locularity of the lesion. Conclusions Our paper highlights that patients with COF who present a lesion located in the maxilla with multilocular aspects and cortical bone perforation tend to show a higher recurrence rate.

Dentinogenic ghost cell tumor (DGCT), a rare, benign odontogenic tumor with aggressive behavior, causes bone destruction and cortical expansion. We report here a case of DGCT in a 38-year-old male, presenting with enormous extraoral protrusion, which radiographically was predominantly radiolucent with radiopaque areas. Microscopically, it was observed to be a solid ameloblastomatous proliferation with pseudoglandular structures associated with clusters of ghost cells. Abundant dentinoid material adjacent to the epithelial sheets containing entrapped epithelial tumor cells was also evident. Immunohistochemistry revealed positivity for pan-cytokeratin (CK), CK-14, CK-7, and CK-19; CD138; and β-catenin. The Ki-67 proliferative index was very low (

Tuberous sclerosis complex (TSC) is an autosomal dominant inherited disease characterized by systemic hamartoma and diverse systemic features. TSC1 and TSC2 are the causative genes, and mental retardation, epileptic seizures, and facial angiofibroma develop in many patients with the disease. The case of a patient with TSC who developed a central odontogenic fibroma of the mandible is reported here. The patient was a 21-year-old woman who was referred with a swelling of the labial gingiva in the region of the right lower lateral incisor and canine. Dental radiography revealed a multilocular radiolucent region with a clear boundary. The right lower lateral incisor and canine were continuous with the lesion and thus were excised en bloc. The lesion was encapsulated and easily dissected. The diagnosis on immunohistological staining was odontogenic fibroma without an epithelial component. TSC1/2 gene mutation causes abnormal activation of mammalian target of rapamycin (mTOR) downstream of the PI3K-AKT pathway. The odontogenic fibroma in this patient was positive for mTOR, suggesting that the development of the odontogenic fibroma was the result of abnormal activation of mTOR, as in angiofibroma. The clinical course of this patient is presented and the developmental mechanism of central odontogenic fibroma is discussed.

Most of the odontogenic keratocysts show an indolent behaviour like non-neoplastic lesions. For this reason, the odontogenic keratocyst was reclassified within the odontogenic cysts category in the WHO 2017 classification. Some odontogenic keratocysts may contain satellite cysts or solid squamoid islands within their wall. Recently, a solid form of odontogenic keratocyst has also been described which is composed entirely of multiple epithelial islands and small cysts in a collagenous stroma. The true nature of this variant is unclear yet. In this article, we present a series of 204 odontogenic keratocyst cases. Clinical and histologic findings of the cases in this series were described. These were also categorised according to the presence of satellite lesions. Additionally, the features of two cases of the solid form of odontogenic keratocysts were compared with those of the previous reports and other histologically similar odontogenic lesions. Current evidence suggests that this variant may be neoplastic and it differs from other odontogenic keratocysts, at least histologically. We believe diagnosing a solid lesion as a cyst is counterintuitive and the term "keratocystic odontogenic tumour" better describes this particular variant. (C) 2018 European Association for Cranio-Maxillo-Facial Surgery.

Objectives The odontogenic keratocyst (OKC) is an aggressive odontogenic cyst that has a high recurrence rate. Apart from PTCH1 mutations, few molecular alterations are described in OKCs. Low expression of microRNAs (miRNAs) miR-15a and/or miR-16-1 in association with increased expression of their target, Bcl-2, have been previously found in OKC. In humans, MIR15A and MIR16-1 are clustered at chromosome position 13 q14, and loss of heterozygosity (LOH) at this locus occurs in different tumors. We aimed to determine whether deletion at 13 q14 is a potential mechanism leading to miR-15a/16-1 aberrant expression in OKC. Methods Genomic DNA was extracted from 15 formalin-fixed, paraffin-embedded microdissected OKC cases. The polymorphic DNA markers D13S272 and D13S273 on chromosome 13 q14.3, around MIR15A/MIR16-1, were amplified by polymerase chain reaction. LOH was examined by capillary electrophoresis DNA-fragment analysis. Results The D13S272 marker had no LOH in 12 informative cases, whereas 2 out of 9 informative cases (22%) had LOH at the D13S273 marker. Conclusions An LOH event at MIR15A/MIR16-1 locus is not common in OKC. The mechanism underlying the regulation of miR-15a and miR-16-1 expression in OKC remains to be determined.

Objective Epigenetic mechanisms, such as DNA methylation, regulate important biological processes as gene expression and it was suggested that these phenomena play important roles in the carcinogenesis and tumor biology. The aim of this review is to provide the current state of knowledge about epigenetic alterations, focusing mainly on DNA methylation, reported in odontogenic tumors. Design Literatures were searched based in the combination of the following keywords: odontogenic tumors, epigenetics, DNA methylation, histone modifications, non-coding RNA, microRNA, DNA methyltransferases. Electronic databases (Medline/PubMed, Scopus and Web of Science) were screened. Results The analysis of epigenetic alterations in different tumors has rapidly increased; however, limited information is available about epigenetic mechanisms involved in the formation of odontogenic tumors. DNA methylation is the most studied epigenetic modification in these tumors and the participation of non-coding RNA’s in odontogenic tumors has been recently addressed. Differential expression of DNA methyltransferases, altered DNA methylation patterns and aberrant expression of non-coding RNA’s were reported in odontogenic tumors. Conclusions Current studies suggest epigenetics as an emerging mechanism, possibly implicated in etiopathogenesis of odontogenic tumors. Deeper understanding of the epigenetic abnormalities in these tumors could show potential applications as biomarkers or therapeutic possibilities in the future.

Objective The present study was designed to analyze the immunolocalization of proteins involved in cytoskeleton remodeling, such as moesin and Rho-A, in benign odontogenic lesions that present with expansive growth and invasive clinical behavior. Materials and methods Expressions of moesin and Rho-A in odontogenic epithelium were evaluated by immunohistochemical analysis in 45 odontogenic lesions using monoclonal antibodies. Results Our results demonstrated strong membranous and cytoplasmic expressions of moesin in the epithelial cells in 66.7% and 44.4% of the odontogenic lesions, respectively. Furthermore, Rho-A expression in odontogenic epithelium was strong in the membrane and cytoplasm of 51.1% and 62.2% of the odontogenic lesions, respectively. A statistically significant correlation was found between the membranous and cytoplasmic expressions of moesin (p = 0.000) and those of Rho-A (p = 0.048) in odontogenic epithelial cells, while no statistically significant correlation was found between moesin and Rho-A expressions (p > 0.05). Conclusions The present study confirmed the strong expressions of moesin and Rho-A by odontogenic epithelial cells, suggesting their involvement in the development of benign odontogenic lesions. However, this study has failed to detect the connection between the moesin and Rho-A interaction in expansive growth and local invasiveness of these lesions.

Purpose To integrate the available data published on squamous odontogenic tumors (SOT) and squamous odontogenic tumor-like proliferations in odontogenic cysts (SOT-LPOC) into a comprehensive analysis of their clinical/radiologic features. Materials and methods An electronic search was undertaken in January 2017. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm a definite diagnosis. Results A total of 74 publications reporting 110 SOTs (102 central, 8 peripheral) and 60 SOT-LPOC were included. Compared to SOT-LPOC, SOT showed lower mean age, no preference regarding maxilla or mandible localization, significant association with cortical bone perforation, multilocular radiographic appearance, and mobility of the tooth/teeth associated with the lesion. While 5 recurrent SOT were reported after enucleation, no recurrent SOT-LPOC was found. Conclusions SOT shows a more aggressive biologic behavior than SOT-LPOC, which supports the hypothesis that the two lesions are distinct clinicopathological conditions.

The keratocystic odontogenic tumor (KCOT) is capable of causing vast osseous destruction. Histopathological examination is pivotal for diagnosis. The diagnostic process can sometimes be hindered by tissue inflammation of KCOTs with loss of defining criteria, resulting in misdiagnosis as an odontogenic jaw cyst. We discuss the possible merits of volumetric analysis when facing this particular diagnostic dilemma and for pathophysiological characterization of KCOTs. We included 114 patients, of whom 27 were histopathologically diagnosed with a KCOT and 87 with dentigerous (n = 41) and periapical cyst (n = 46). Semiautomatic segmentation and radiological analysis of preoperative cone beam computed tomography (CBCT) image data was carried out using ITK-SNAP. The mean volumetric extent of KCOTs is significantly higher compared to non-neoplastic odontogenic jaw cysts (p = 0.001). The mean volume and standard deviation for KCOTs and non-neoplastic odontogenic jaw cysts was 10381 mm 3 ± 6410 and 5813 mm 3 ± 4425, respectively. Volumetric analysis reveals that KCOTs significantly exceed the mean size of non-neoplastic odontogenic jaw cysts, adding an argument in favor of the neoplastic nature of KCOTs. In the case of difficult histopathological examination, lesions with a size exceeding a value of about 3000 mm 3 could be considered for close clinico-radiologic follow-up.

Sclerosing odontogenic carcinoma (SOC) is a primary intraosseous carcinoma of the jaws that has been listed as a separate entity for the first time in the latest version of the World Health Organization classification of Head and Neck Tumours (2017). The aim of this study was to analyse and interpret the existing literature on SOC in the context of a clinical case treated in the authors' department. A systematic search of the PubMed database was performed in accordance with the PRISMA guidelines, yielding nine cases of SOC reported so far. In summary, characteristic clinical and radiological features of SOC include asymptomatic swelling, location predominantly in the mandible, tumour primarily lytic in appearance, presence of cortical bone destruction, and lack of metastatic spread. Due to the rarity of the disease, close collaboration between oral/maxillofacial surgeons and pathologists is crucial to avoid misdiagnosis. With complete excision, no recurrence of SOC should be expected.