MMP13 Expression and Activity Suggest Its Role in Bone Resorption in Ameloblastomas.

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

Primordial Odontogenic Tumor: A Review of the Literature and Report of Three New Patients.

The primordial odontogenic tumor (POT) is a rare mixed odontogenic tumor composed of mesenchymal cells, columnar odontogenic epithelium, and fibromyxoid stroma affecting the posterior mandible of children and adolescents. Herein, we report 3 patients with POT and the clinicopathological features of POT previously reported in the literature. A 12-year-old, 19-year-old, and 4-year-old patient presented an asymptomatic swelling in the posterior maxilla and posterior mandible. Imaging exams revealed radiolucent lesions associated with unerupted teeth. The lesions were surgically removed, and the histopathological examination revealed spindle-to-ovoid mesenchymal cells in a fibromyxoid stroma surfaced by columnar odontogenic epithelial cells with reverse nuclear polarization. Deposition of mineralized tissue was observed. The final diagnosis was POT, and patients did not exhibit signs of recurrence. POT should be included in the differential diagnoses of intraosseous lesions in the posterior mandible in pediatric patients.

Adenoid Ameloblastoma: The Newly Recognized Odontogenic Tumor - A Case Report.

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

Targeted therapies in ameloblastomas and amelobastic carcinoma-A systematic review.

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

Tumor odontogénico epitelial calcificante en la rama mandibular. Informe de un caso clínico basado en una actualización bibliográfica / Calcifying epithelial odontogenic tumor in the mandibular ramus. A case report based on a literature update

Objetivo: Presentar un caso clínico de un tumor odon- togénico epitelial calcificante (TOEC), así como una revisión de la literatura disponible sobre esta neoplasia para contribuir al análisis del mejor método de tratamiento de la patología. Caso clínico: Se presenta el caso de una paciente mujer de 35 años con un tumor odontogénico epitelial calcifican- te que recibió tratamiento de enucleación quirúrgica con una evolución favorable y seguimiento de 5 años por medio de evaluación clínica y radiológica. La elección terapéutica se basó en el resultado de un análisis exhaustivo de la literatura para determinar el mejor abordaje de la neoplasia (AU)

Aim: To present a clinical case of a calcifying epithelial odontogenic tumor (CEOT), as well as a review of the availa- ble literature on this neoplasia to contribute to the analysis of the best treatment method for the pathology. Clinical case: The case of a 35-year-old patient with a calcifying epithelial odontogenic tumor who received surgical enucleation treatment with a favorable evolution and 5-year follow-up through clinical and radiological evaluation is pre- sented. The therapeutic choice was based on the result of an exhaustive analysis of the literature to determine the best ap- proach to the neoplasia (AU))

Prevalence of BRAF p.V600E and Detection Methods in Benign Mixed and Malignant Odontogenic Tumors: A Systematic Review.

BACKGROUND: The BRAF p.V600E genetic variant facilitates the pathogenesis of various tumors by triggering tumor proliferation and progression. The aim of this study was to analyze the prevalence of BRAF p.V600E in benign mixed epithelial and mesenchymal and malignant odontogenic tumors. In addition, we discussed the different detection methods used to assess for aberrant BRAF. METHODS: This systematic review followed the PRISMA guidelines and was registered in Prospero (CRD42023445689). A comprehensive search of the PubMed/MEDLINE, Scopus, Web of Science, and Embase electronic databases was performed to answer the question "What is the prevalence of the BRAF p.V600E mutation in benign mixed and malignant odontogenic tumors?" The methodological quality of the selected studies was assessed using the JBI's Critical Appraisal Tool. RESULTS: Initially, 387 records were identified, but only 11 articles met the inclusion criteria. A total of 70 patients with benign mixed epithelial and mesenchymal odontogenic tumors and 63 with malignant odontogenic tumors were included in the analysis. We found that the BRAF p.V600E mutation had a prevalence of 31.42% in mixed tumors and 26.98% in malignant odontogenic tumors. Moreover, immunohistochemistry showed high concordance with DNA-based molecular methods. CONCLUSION: In general, the BRAF p.V600E variant exhibited a prominent prevalence in mixed and malignant odontogenic tumors. However, most of the findings are based on small cohorts of patients and further studies with larger cohorts are needed.

Actualización en el Diagnóstico y Tratamiento del Fibroma Ameloblástico: Revisión Sistemática

El fibroma ameloblástico (FA) es una neoplasia benigna con potencial de recurrencia y transformación maligna que afecta los huesos maxilofaciales. Se analizaron casos recientes de FA para describir sus características clínicas y opciones de tratamiento. El objetivo de este estudio es mejorar la comprensión de esta enfermedad poco común y brindar información relevante para el diagnóstico y manejo de los pacientes. Se realizó una revisión de la literatura en busca de reportes de caso de FA publicados en los últimos 5 años. Después de eliminar duplicados, se seleccionaron 16 estudios para su análisis. Se recopilaron datos sociodemográficos, ubicación de la lesión, signos clínicos, hallazgos radiográficos y opciones de tratamiento. Los estudios incluidos en el análisis reportaron casos de FA en pacientes con edades entre 4 y 21 años. Se observó una ligera predominancia en hombres. La ubicación más común de la lesión fue la mandíbula posterior. Los signos clínicos más frecuentes fueron el aumento de volumen óseo y el dolor. Radiográficamente, se encontraron principalmente lesiones radiolúcidas multiloculares. El tratamiento más común fue la enucleación de la lesión. No se observaron recurrencias durante el seguimiento de los casos reportados. Los resultados coinciden con la literatura reciente, proporcionando información actualizada sobre el perfil clínico y radiográfico del FA. La enucleación se muestra como una opción efectiva de tratamiento. Estos hallazgos contribuyen al diagnóstico preciso y al manejo adecuado de los pacientes con FA, resaltando la importancia de comprender las características clínicas de esta neoplasia.

Ameloblastic fibroma (AF) is a benign neoplasm with the potential for recurrence and malignant transformation that affects the maxillofacial bones. Recent cases of AF were analyzed to describe their clinical characteristics and treatment options. The objective of this study is to enhance understanding of this rare disease and provide relevant information for the diagnosis and management of patients. A literature review was conducted to identify case reports of AF published in the past 5 years. After removing duplicates, 16 studies were selected for analysis. Sociodemographic data, lesion location, clinical signs, radiographic findings, and treatment options were collected. The included studies reported cases of AF in patients aged between 4 and 21 years. There was a slight male predominance. The most common location of the lesion was the posterior mandible. The most frequent clinical signs were increased bone volume and pain. Radiographically, predominantly multilocular radiolucent lesions were found. The most common treatment was lesion enucleation. No recurrences were observed during the follow-up of the reported cases. The results align with recent literature, providing updated information on the clinical and radiographic profile of AF. Enucleation emerges as an effective treatment option. These findings contribute to accurate diagnosis and appropriate management of patients with AF, highlighting the importance of understanding the clinical characteristics of this neoplasm.

Squamous Odontogenic Tumor in the Posterior Region of Maxilla.

Squamous odontogenic tumor (SOT) is a rare benign but locally infiltrative tumor often misdiagnosed as other entities, such as ameloblastoma and squamous cell carcinoma, due to overlapping morphological findings. We document here the clinicopathological and imaging findings of an aggressive intraosseous SOT in the posterior left region of the maxilla in a 25-year-old male patient. On intraoral examination, the tumor extended from the region of the left lateral incisor to the upper left premolar and was covered by reddish mucosa, with discrete areas of ulceration. Imaging exams revealed an osteolytic lesion causing thinning, erosion, and buccal and lingual cortical plate perforation associated with an impacted canine. Microscopically, the tumor showed a proliferation of islands of well-differentiated squamous epithelium in a variably collagenized background. The peripheral cells of the islands were flat or slightly cuboidal and did not exhibit nuclei with peripheral palisade and reverse polarization. The diagnosis of SOT was rendered. The patient underwent surgical resection and has been under clinical follow-up for approximately 12 months with no signs of recurrence. A careful morphological evaluation is essential to avoid misdiagnosis and ensure a satisfactory treatment approach.

A Systematic Review of Adenoid Ameloblastoma: A Newly Recognized Entity.

BACKGROUND: Recently, a new odontogenic tumor has been described, the so-called adenoid ameloblastoma (AdAM). The aim of this review was to determine the clinical and imaging features of AdAM and to describe its main histopathological findings. METHODS: The systematic review included published cases with a diagnosis of AdAM in the gnathic bones, which had sufficient clinical, imaging, and histopathological data to confirm its diagnosis. The following histopathological diagnostic criteria were adopted: presence of ameloblastoma-like components, duct-like structures, spiral cellular condensations, and a cribriform architecture. RESULTS: Fifteen articles, corresponding to 30 cases of AdAM, were selected. Most cases affected men (63.3%), with a slight preference for the mandible (16:14) and the posterior region of gnathic bones was the most commonly affected site. The mean age at diagnosis was 40.8 years. Clinically, the lesions usually presented as a swelling (53.3%) and, radiographically, as a well-defined radiolucency (33.4%). Surgical resection (40%) was the most frequently adopted treatment and recurrence occurred in 30% of cases. Microscopic examination showed cribriform areas in most AdAM cases (93.3%); duct-like structures and spiral cellular condensations were seen in 100% of the cases. CONCLUSION: The small number of reported cases, the existence of erroneous diagnoses, and the adoption of initial conservative management make it difficult to determine whether AdAM has a higher risk of recurrence or more aggressive biological behavior than conventional ameloblastomas.

Quiste odontogénico ortoqueratinizado. A propósito de un caso

El quiste odontogénico ortoqueratinizado es un quiste odontogénico de desarrollo poco común. Los maxilares son el sitio más común de afectación. Los quistes mandibulares con queratinización, el queratoquiste odontogénico (OKC) y el quiste odontogénico ortoqueratinizado (OOC) son los que han atraído una mayor atención. Se presenta el caso de una paciente de sexo femenino de 34 años de edad, con historia de 2 meses de evolución de tumefacción de crecimiento progresivo en región de seno maxilar izquierdo acompañado de rinorrea mucopurulenta y salida se secreción purulenta por fístula oroantral. Se realiza cirugía bajo anestesia general, se constata una lesión quística de contenido queratínico en seno maxilar cuya histopatología retorna compatible con Quiste odontogénico ortoqueratinizado.

The orthokeratinized odontogenic cyst is an odontogenic cyst of uncommon development. The jaws are the most common site of involvement. Cysts of the jaw with keratinization, the odontogenic keratocyst (OKC), and the orthokeratinized odontogenic cyst (OOC) have attracted the most attention. The case of a 34-year-old female patient is presented, with a 2-month history of progressively growing swelling in the region of the left maxillary sinus accompanied by mucopurulent rhinorrhea and purulent discharge from an oroantral fistula. Surgery is performed under general anesthesia, a cystic lesion with keratin content is verified in the maxillary sinus whose histopathology returns compatible with orthokeratinized odontogenic cyst.

Quiste odontogénico ortoqueratinizado. A propósito de un caso / Orthokeratinized odontogenic cyst. A case report

El quiste odontogénico ortoqueratinizado es un quiste odontogénico de desarrollo poco común. Los maxilares son el sitio más común de afectación. Los quistes mandibulares con queratinización, el queratoquiste odontogénico (OKC) y el quiste odontogénico ortoqueratinizado (OOC) son los que han atraído una mayor atención. Se presenta el caso de una paciente de sexo femenino de 34 años de edad, con historia de 2 meses de evolución de tumefacción de crecimiento progresivo en región de seno maxilar izquierdo acompañado de rinorrea mucopurulenta y salida se secreción purulenta por fístula oroantral. Se realiza cirugía bajo anestesia general, se constata una lesión quística de contenido queratínico en seno maxilar cuya histopatología retorna compatible con Quiste odontogénico ortoqueratinizado.

The orthokeratinized odontogenic cyst is an odontogenic cyst of uncommon development. The jaws are the most common site of involvement. Cysts of the jaw with keratinization, the odontogenic keratocyst (OKC), and the orthokeratinized odontogenic cyst (OOC) have attracted the most attention. The case of a 34-year-old female patient is presented, with a 2-month history of progressively growing swelling in the region of the left maxillary sinus accompanied by mucopurulent rhinorrhea and purulent discharge from an oroantral fistula. Surgery is performed under general anesthesia, a cystic lesion with keratin content is verified in the maxillary sinus whose histopathology returns compatible with orthokeratinized odontogenic cyst.

Adenomatoid odontogenic tumor: Features of ameloblastic-like epithelial cells differentiation, secretion, and the nature of tumor cells products.

BACKGROUND: This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors. METHODS: We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34. RESULTS: Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them. Epithelial cells of the rosettes can differentiate into ameloblastic-like cells. This phenomenon probably occurs due to an induction phenomenon between these cells. The secretion of collagen I is probably a brief event. Amelogenin-positive areas were interspersed by epithelial cells in the lace-like areas, outside the rosettes and distant from the ameloblastic-like cells. CONCLUSIONS: There are at least two types of eosinophilic material in different areas within the tumor, one in the rosette and solid areas and another in lace-like areas. The secreted eosinophilic material in the rosettes and solid areas is probably a product of well-differentiated ameloblastic-like cells. It is positive for collagen I and negative for amelogenin, whereas some eosinophilic materials in the lace-like areas are positive for amelogenin. We hypothesize that the latter eosinophilic material could be a product of odontogenic cuboidal epithelial or intermediate stratum-like epithelial cells.

A Systematic Review of the Granular Cell Odontogenic Fibroma and Report of a New Case.

BACKGROUND: Granular Cell Odontogenic Fibroma (GCOF) is a rare odontogenic neoplasm reported over time with different names. The purpose of this study is to review all available data on the GCOF in the scientific literature, with a summary of all reported cases and a report of a new case. METHODS: This review was conducted following the PRISMA guidelines. An electronic search was performed up to November 2022. RESULTS: Thirty-nine studies reporting fifty-three cases were included. GCOF is a rare neoplasm among the odontogenic tumors, with a higher prevalence in women of the middle-aged and white population. This lesion occurs mostly on the posterior region of the mandible. Furthermore, based on clinical, radiographic, and histopathologic features, conservative treatment was the most reported choice with recurrence reported in two cases. CONCLUSION: GCOF remains controversial due to the still unsolved histogenesis.

Tratamiento conservador del fibromixoma odontogénico en mandíbula: reporte de dos casos / Conservative treatment of odontogenic fibromyxoma in the mandible: report of two cases

RESUMEN Introducción: El fibromixoma odontogénico es un tumor benigno poco frecuente de origen mesenquimal. Las lesiones menores pueden ser asintomáticas y se descubren sólo durante un examen radiográfico de rutina, y las lesiones mayores se asocian a expansión indolora del hueso involucrado, con desplazamiento de dientes y perforación ósea. La opción de tratamiento es quirúrgica existiendo desde el tratamiento conservador hasta la escisión radical. Reporte de caso: Presentamos dos casos de fibromixoma en mandíbula en una mujer de 17 años y varón de 18 años. El diagnóstico fue anatomopatológico. En ambos se realizó el tratamiento conservador de enucleación con osteotomía periférica y extracción de las piezas dentarias involucradas, con evolución favorable. Discusión: El tratamiento conservador con abordaje intrabucal es una alternativa humanística que mantiene su valor de éxito, evolución favorable y gran aceptación por los pacientes.

ABSTRACT Introduction: Odontogenic fibromyxoma is a rare benign tumor of mesenchymal origin. Small tumors may be asymptomatic and are discovered only during the routine radiographic examination, and large tumors are associated with the painless expansion of bone with the displacement of teeth and bone perforation. The treatment option is surgical and can range from conservative treatment to radical excision. Case Report: We report two cases of fibromyxoma in the mandible in a 17-year-old woman and an 18-year-old man. The diagnosis was anatomopathological. Both underwent conservative enucleation treatment with peripheral osteotomy and extraction of the affected teeth with favorable evolution. Discussion: Conservative treatment with an intraoral approach is a humanistic alternative that maintains its value of success, favorable evolution, and great acceptance by patients.

Interrogation of TERT promoter hotspot mutations in ameloblastoma and ameloblastic carcinoma.

BACKGROUND: TERT promoter mutations increase telomerase activity, conferring cell immortality. The coexistence of TERT promoter mutations with BRAFV600E is associated with aggressiveness. Ameloblastoma and ameloblastic carcinoma are infiltrative neoplasms that harbor BRAFV600E; however, it remains unknown if these odontogenic tumors also show TERT promoter mutations. METHODS: Genomic DNA of paraffin-embedded ameloblastomas (n = 6) and ameloblastic carcinomas (n = 3) were Sanger-sequenced to assess the hotspot TERT promoter mutations C228T and C250T. BRAFV600E status was screened by TaqMan allele-specific quantitative polymerase chain reaction. RESULTS: None of the samples harbored TERT promoter mutations. The BRAFV600E mutation was positive in 3 of 6 of ameloblastomas and in 1 of 3 of ameloblastic carcinomas. CONCLUSION: The absence of TERT promoter mutation in the samples indicates that this molecular event is not relevant to the tumors' pathogenesis. Further studies are necessary to explore undefined genetic or epigenetic mechanisms related to TERT-upregulation in ameloblastoma, and the telomerase activity in ameloblastic carcinoma.

Calcifying odontogenic cyst with AOT-like features: a case report and literature review / Cisto odontogênico calcificante com características adenomatóides: relato de caso e revisão de literatura

Odontogenic lesions are a heterogeneous group of diseases that presents differences in their biological behavior and the occurrence of variable inductive interactions. Calcifying odontogenic cyst (COC), or Gorlin's cyst, is a well-recognized example of these lesions. We describe a case of COC with AOT-like areas and highlights its morphological diversity. A 60-year-old pheoderma man presented with a large swelling in the anterior buccal region of the mandible. Panoramic radiography revealed a well-defined, unilocular, radiolucent lesion associated with important root resorption. Complete enucleation of the lesion was performed and the histopathological findings met the criteria for the diagnosis of COC, although the cyst exhibited unusual AOT-like features. The patient has been recurrence free for 6 months after surgery. COCs with AOT-like features are rare, and reflect the multipotentiality and complexity of the inductive effects of the odontogenic epithelium with the ectomesenchyme. Enucleation seems to be the most indicated treatment, similar to classical COC (AU)

As lesões odontogênicas são um grupo heterogêneo de patologias que apresentam diferenças no seu comportamento biológico, e ocorrência de interações indutivas variáveis. O cisto odontogênico calcificante (COC), ou cisto de Gorlin, é um exemplo bem conhecido destas lesões. Descrevemos um caso de COC com áreas adenomatóides e destacamos a sua diversidade morfológica. Paciente do sexo masculino, 60 anos de idade, apresentou um aumento de volume na região anterior da mandíbula. A radiografia panorâmica revelou uma lesão bem definida, unilocular e radiolúcida associada a uma reabsorção radicular importante. A enucleação completa da lesão foi realizada e os achados histopatológicos preencheram os critérios para o diagnóstico de COC, embora o cisto exibisse características adenomatóides pouco usuais. O paciente permanece livre de recidivas durante 6 meses após a cirurgia. Os COCs com características adenomatóides são raros, e refletem a multipotencialidade e complexidade dos efeitos indutivos do epitélio odontogênico com o ectomesênquima. A enucleação parece ser o tratamento mais indicado, semelhante ao COC clássico. (AU)

Higher immunoexpression of CK14 from the Wnt-1/β-catenin pathway in the development of odontomas

Abstract Tooth development depends on a series of reciprocal signaling interactions between the oral epithelium and ectomesenchyme. This study aimed to investigate the role of CK14, a protein involved in Wnt-1/β-catenin signaling, in odontogenesis and the development of odontomas. This cross-sectional, retrospective, immunohistochemical study analyzed 30 compound odontomas, 30 complex odontomas, and 17 tooth germs. Higher immunoexpression of CK14 was observed in odontogenic epithelial cells of tooth germs (p < 0.001) and odontogenic epithelial cells of odontomas (p < 0.001). There was higher immunoexpression of Wnt-1 and β-catenin proteins in epithelial cells of tooth germs (p = 0.002 and p < 0.001, respectively), as well as in the ectomesenchyme of odontomas (p = 0.003 and p < 0.001, respectively). β-Catenin was moderately and significantly correlated with CK14 in the membrane of reduced enamel epithelial cells in odontomas (p = 0.007). Higher immunoexpression of CK14 was observed in the odontogenic epithelium during the bud and cap stages and lower immunoexpression in the internal enamel epithelium during the bell stage. In odontomas, lower expression of Wnt-1/β-catenin and higher immunoexpression of CK14 were found in odontogenic epithelial cells, especially adjacent to the mineralized material resembling the tooth formed in these lesions.

Resumo O desenvolvimento dentário depende de uma série de interações de sinalização recíproca entre o epitélio oral e o ectomesênquima. O objetivo deste estudo foi investigar o papel da CK14 das vias WNT-1/β-catenina na odontogênese e no desenvolvimento de odontomas. Este estudo transversal, retrospectivo, imuno-histoquímico analisou 30 odontomas compostos, 30 odontomas complexos e 17 germes dentários. A CK14 apresentou maior imunoexpressão em células epiteliais odontogênicas de germes dentários (p<0,001) e em células epiteliais odontogênicas de odontomas (p<0,001). A Wnt-1 e a β-catenina apresentaram maior imunoexpressão de proteínas nas células epiteliais dos germes dentários (p = 0,002 e p<0,001, respectivamente), bem como no ectomesênquima dos odontomas (p = 0,003 e p < 0,001, respectivamente). A β-catenina correlacionou-se moderada e significativamente com a CK14 na membrana de células epiteliais reduzidas do esmalte em odontomas (p = 0,007). Maior imunoexpressão da CK14 foi observada no epitélio odontogênico nos estágios de botão e capuz com menor imunoexpressão no epitélio interno do órgão do esmalte no estágio de sino. Nos odontomas, foi observado menor expressão de Wnt-1/β-catenina e maior imunoexpressão da CK14 presente nas células epiteliais odontogênicas, especialmente, vizinhas ao material mineralizado semelhante ao dente formado nessas lesões.

Mixoma odontogénico de larga data en el maxilar. Reporte de caso / Long-Standing odontogenic myxoma of the maxilla. Case Report

Introducción: el mixoma odontogénico es una neoplasia benigna, poco frecuente, de origen mesenquimal proveniente del órgano dentario, es localmente invasivo y no hace metástasis. Su localización más frecuente es a nivel de la mandíbula y poco frecuente en el maxilar. Objetivo: describir las características que presenta un mixoma odontogénico de larga data en el maxilar. Presentación del caso: paciente de sexo masculino de 23 años de edad, soltero, de profesión comerciante, acude a la Catedra de Patología Bucal de la Facultad de Odontología de la Universidad Nacional de Asunción por presentar una deformidad en la región facial del lado derecho, presente desde la infancia con crecimiento lento sin sintomatología dolorosa. Se realizó una biopsia incisional, tomando una muestra de más de 1 cm de la capsula tumoral para su estudio histopatológico; a partir de la cual se informa sobre un tumor odontogénico mesenquimal compatible con el mixoma odontogénico. Se realizó el tratamiento de una maxilectomía con márgenes de seguridad y el estudio anatomopatológico de todo el tumor extirpado confirmó el diagnóstico de Mixofibroma odontogénico de 2,5 cm de diámetro máximo. Conclusión: un diagnóstico precoz de tumores como los mixomas, que son de crecimiento lento e infiltrante, podría garantizar terapéuticas menos agresivas e invasivas como las del caso presentado, otorgando así mejor pronóstico como calidad de vida a los pacientes.

Introduction: Odontogenic myxoma is a rare benign neoplasm of mesenchymal origin originating from the dental organ, it is locally invasive and does not metastasize. Its most frequent location is at the level of the mandible and infrequently in the maxilla. Objective: To describe the characteristics of a long-standing odontogenic myxoma in the maxilla. Presentation of the case: Male patient, 23 years of age, single, businessman, came to the Department of Oral Pathology of the Faculty of Dentistry of the National University of Asuncion for presenting a deformity in the facial region on the right side, present since childhood with slow growth and no painful symptomatology. An incisional biopsy was performed, taking a sample of more than 1cm of the tumor capsule, for histopathological study; reporting a mesenchymal odontogenic tumor compatible with odontogenic myxoma. A maxillectomy treatment with safety margins performed and the anatomopathological study of the entire excised tumor confirmed the diagnosis of odontogenic myxofibroma with a maximum diameter of 2.5 cm. Conclusion: An early diagnosis of tumors such as myxomas, which are slow-growing and infiltrative, could guarantee less aggressive and invasive therapies such as those in the case presented, thus providing patients with a better prognosis and quality of life.

Conventional Ameloblastoma. A Case Report with Microarray and Bioinformatic Analysis.

Ameloblastoma is a rare benign epithelial odontogenic neoplasm, but with great clinical implications, as despite its benignity and slow growth, most cases are locally aggressive with a significant recurrence rate. Histological, cellular, or molecular analyses of its pathogenesis have confirmed the complexity of this neoplasm. We present the case of a 20-year-old patient with a suggestive clinical and radiographic diagnosis of ameloblastoma. An incisional biopsy was obtained confirming the diagnosis of conventional ameloblastoma. Left hemimandibulectomy and plate reconstruction were performed. Histopathological analysis of the surgical specimen confirmed the conventional ameloblastoma with a plexiform pattern and significant areas of cystic degeneration and amyloid-like-like deposits. Additionally, a microarray was carried out with bioinformatic analysis for the enrichment, protein interaction, and determination of eight hub genes (CRP, BCHE, APP, AKT1, AGT, ACTC1, ADAM10, and APOA2) related to their pathogenesis.