Ameloblastoma uniquístico patrón mural: Reporte de un caso / Unicystic mural ameloblastoma: A case report

El ameloblastoma es un tumor odontogénico agresivo que se clasifica en uniquístico, extraóseo/periférico y metastatizante. Una mujer de 42 años acudió al Servicio de Cirugía Oral y Maxilofacial por aumento de volumen hemifacial izquierdo de 6 meses de evolución. Al examen se observó aumento de volumen de la región parotídea y submandibular izquierda, abombamiento tablas óseas mandibulares y movilidad dental. La tomografía axial computarizada reveló una lesión de aspecto quístico en la región mandibular. Se realizó la biopsia incisional y el tratamiento quirúrgico conservador. El diagnóstico histopatológico fue ameloblastoma uniquístico patrón mural. Luego de seis meses de descompresión, se realizó una nueva biopsia incisional, curetaje óseo y se aplicó solución de Carnoy. Once meses posteriores a la primera intervención, se constató radiográficamente aposición ósea de la lesión. El tratamiento de estos ameloblastomas continúa siendo controversial por lo que cada caso se debe abordar de manera única.

Ameloblastoma is an aggressive odontogenic tumor classified as unicystic, extraosseous / peripheral, and metastasizing. A 42-year-old woman was attended at the Oral and Maxillofacial Surgery Service due to a 6-month facial asymmetry. Clinically, we observed a volume increase of the left parotid and submandibular region, bulging of the mandibular bone tables and dental mobility. Computed Tomography revealed a cystic-like lesion in the mandibular region. An incisional biopsy and conservative surgical treatment were performed. The histopathological diagnosis was unicystic ameloblastoma, mural pattern. After six months of decompression, a new incisional biopsy and bone curettage were performed, and Carnoy's solution was applied. Eleven months after the first intervention, bone apposition was observed in the x-ray. The treatment of these ameloblastomas continues to be controversial, so every case should be approached in a unique manner.

Expression level and proteolytic activity of MMP-2 and MMP-9 in dental follicles, dentigerous cysts, odontogenic keratocysts and unicystic ameloblastomas.

Matrix metalloproteinases (MMPs) are involved in remodeling the extracellular matrix, but also participate in the development of physiopathologic processes. As they are overexpressed in different types of epithelial cancers, it has been suggested that their level expression could explain the different biological behavior between odontogenic cysts and tumors. Here, we compared the expression level and proteolytic activities of MMP-2 and MMP-9 in dental follicles, dentigerous cysts, odontogenic keratocysts and unicystic ameloblastomas. We found similar expression of MMP-2 in all tissues, but a higher activity in cystic and tumor lesions than follicles. On the other hand, MMP-9 expression and activity was greater in cysts and ameloblastoma than in follicles. However, no differences were found in expression or activity of both MMPs between cystic and tumor injuries, suggesting that they could participate in the growth of these lesions, but they cannot define their different biological behavior.

A meta-analysis on the presentation of Unicystic Ameloblastoma in the jaws and the consequences for their treatment.

INTRODUCTION: This meta-analysis provides reliable data on the prevalence of unicystic ameloblastomas (UA's) among solid/multicystic ameloblastomas (SMA's), as well the ratio of their presence in the maxilla and mandible and in the tooth-bearing area versus the posterior regions of the mandible, including the third molar region and ascending ramus. MATERIAL AND METHODS: A systematic review and meta-analysis was performed according to PRISMA guideline using the strategy ((unicystic ameloblastoma) OR (((ameloblastoma) OR (solid ameloblastoma)) OR (multicystic ameloblastoma))) NOT ((((systematic review) OR (literature review)) OR (case report)) OR (Immunohistochemical)). DISCUSSION: The study included 3856 SMA's and 1537 UA's, which amounted to 28.5% UA's. Of the 380 cases of UA from twelve articles that mentioned the involved jaws, 355 were in the mandible and 25 in the maxilla. The preponderance for the mandible is much higher than reports from previous studies of smaller series. Only five articles mentioned the location within the mandible. The vast majority was in the posterior area. CONCLUSION: The consequences for treatment were discussed, with an emphasis on the approach to unicystic lesions in the posterior part of the mandible for which a protocol is suggested.

Tratamento conservador de ameloblastomaunicístico variante plexiforme: relato de caso / Conservative treatment of unicystic ameloblastoma, plexiforme variation: case report

Introdução: O ameloblastoma é uma neoplasia benigna, localmente invasiva, originada do epitélio odontogênico que ainda não possui sua etiologia esclarecida. Este tumor pode ser identificado radiograficamente como unicístico ou multicístico e geralmente, está relacionado com um dente incluso. O tratamento desta patologia do complexo maxilofacial que acomete tanto a maxila quanto a mandíbula, é baseado no diagnóstico clínico, imagens (raios x (RX), tomografia computadorizada (TC) e histopatológico. O objetivo deste trabalho é descrever e avaliar através de tomografia computadorizada (TC), o tamanho do tumor durante o período em que foi submetido à descompressão, para que as dimensões do mesmo possam ser mensuradas e comparadas em intervalos, dessa forma, comprovar a efetividade dos métodos de descompressão e marsupialização quando bem indicados.Relato de caso:No presente relato de caso, o paciente apresenta ameloblastoma unicístico de variante histológica plexiforme, conforme o exame histopatológico e está sendo tratado por meio de descompressão com a finalidade de se obter a diminuição do volume da lesão cística e consequente neoformação óssea, uma vez que a descompressão possibilita este processo. Considerações finais:O tratamento conservador pode surtir efeito tal como nesse caso em que se evidenciou a regressão do tamanho do tumor e a neoformação de estruturas ósseas antes acometidas pela patologia... (AU)

Introduction: Ameloblastoma is a benign neoplasm, locally invasive, originating from the odontogenic epithelium that still does not have a clear etiology. This tumor can be radiographically identified as unicystic or multicystic and is usually related to an included tooth. The treatment of this pathology of the maxillofacial complex that affects both the maxilla and the mandible is based on clinical diagnosis, images (x-rays (X-rays), computed tomography (CT) and histopathology. The objective of this work is to describe and evaluate using computed tomography (CT), the size of the tumor during the period in which it was subjected to decompression, so that its dimensions can be measured and compared at intervals, thus proving the effectiveness of the methods of decompression and marsupialization when well indicated. Case report: In the present case report, the patient has unicystic ameloblastoma of a plexiform histological variant, according to the histopathological examination and is being treated by means of decompression in order to obtain a decrease in the volume of the cystic lesion and consequent bone neoformation, once that decompression makes this process possible. Final considerations: The conserved treatment or it can have an effect as in this case, in which the regression of the tumor size and the new formation of bone structures that were previously affected by the pathology were evidenced... (AU)

Comparative Study of the Minichromosome Maintenance Proteins Complex (MCM 4/5/6) in Ameloblastoma and Unicystic Ameloblastoma.

INTRODUCTION: Solid/conventional ameloblastoma (AM) and unicystic ameloblastoma (UAM) are the most frequent benign epithelial odontogenic tumors located in the maxillary region, and their treatment usually consists of extensive surgical resection. Therefore, it is relevant to study molecular markers to better understand the biological behavior of these tumors. The aim of this study was to describe and compare the expression of proteins related to cellular proliferation: Ki-67 and MCM4-6 complex. MATERIALS AND METHODS: An immunohistochemistry technique was performed, with antibodies against Ki-67, MCM4, MCM5, and MCM6, in 10 AM and 10 UAM tumors. The results were quantified using label index and analyzed statistically. RESULTS: AM and UAM had greater expression of MCM6, followed by MCM5, MCM4, and Ki-67 ( P < .05). Immunoexpression of Ki-67 and MCM5 was exclusively nuclear, whereas the expression of MCM4 and MCM6 was nuclear and cytoplasmic. CONCLUSION: The results suggest that MCM5 is a trustable cell proliferation marker with higher sensitivity compared with Ki-67 and may be useful to predict the biological behavior of AM and UAM. Despite this, further studies are necessary, including a correlation with clinical parameters to confirm these findings.

Clinico-radiologic features of four cases of ameloblastoma

Ameloblastomas are jaw tumors that are locally aggressive with a high capacity for recurrence. It arises from the epithelium of the dental lamina. Radiograph remains the first and an essential investigation, despite the development of various cross-sectional imaging modalities. Aim: This article intends to describe the clinical findings and orthopantomograph (OPG) supported by computed tomography scan (CT scan) and MRI of four cases of ameloblastomas in the hospital University Sains Malaysia. Materials and methods: Data concerning the patients' ages, sex, tumor locations, and surgical treatment history, as well as the radiographic findings, were analysed. Results: The patients' ages ranged from 23 to 41 years (mean, 30.5 years). The gender of patients were two male (50%) and 2 (50%) females. Three cases (75%) of ameloblastomas located in the mandible and only one case found in the maxilla. The swelling was the most common symptom and experienced by all patients. Radiographically, two cases were unilocular with a well-demarcated border, and the remaining 2 cases were multilocular. Typical features of unicystic ameloblastoma appeared in case 1. This case previously presented with a lesion in the same area diagnosed as a dentigerous cyst. The other 3 cases showed variant types of ameloblastoma. These were Plexiform, Acanthomatous and Granular cell type; follicular and plexiform type; and follicular and plexiform type in case 2, 3 and 4 respectively. Conclusion: In conclusions, determination the location and density of jaws lesion and its margin relation to the tooth using radiological tool accompanied with clinical data, aids in the narrowing of the differential diagnosis and it is necessary for early diagnosis of ameloblastoma. A Long-term follow-up at regular intervals after surgery is recommended for all ameloblastomas cases

Ameloblastoma uniquístico plexiforme: a propósito de un caso / Plexiform unicystic ameloblastoma: a propos of a case

El ameloblastoma es un tumor odontogénico benigno de origen epitelialcon estroma fi broso maduro sin ectomesénquima odontogénico, decomportamiento localmente agresivo e infi ltrante con alta capacidad de recidiva. Representa entre 11 y 13 por ciento de los tumores odontogénicosmandibulares y 1 por ciento de los tumores y quistes maxilomandibulares. El tratamiento debe orientarse de acuerdo con el potencial del tumor,las características del crecimiento según su variable clínica y el tipo histológico. Debe ser un tratamiento que asegure un mejor pronóstico para el paciente

The ameloblastoma is a benign odontogenic tumor of epithelial origin with mature fi brous stroma, without odontogenic ectomesenchyme. It exhibits locally aggressive and invasive behavior, with a high level of recurrence. Ameloblastomata account for between 11 and 13% of mandibular odontogenic tumors, and 1% of maxillo-mandibular tumors and cysts. Treatment should be guided by the potential of the tumor and its growth characteristics based on the clinical variable and histological type, the preferred treatment being that which ensures the best prognosis for the patient.

Mural unicystic ameloblastoma crossing the midline: a rare case report / Ameloblastoma uniquístico mural traspasando la línea mediana: reporte de un caso infrecuente

Ameloblastoma is a benign odontogenic neoplasm which frequently affects the mandible. The term ameloblastoma includes several clinico-radiological and histological types. Apart from the most commonly encountered clinico- pathologic models there are few variants, whose biological profile is unknown or not elicited. The reason for lack of understanding is the scarcity of case report published in the literature. Among the types, unicystic ameloblastoma is the least encountered either it presents as unilocular or multilocular radiolucency, but peculiar radiographic presentation of multilocular radiolucency in posterior mandible with unilocular radiographic appearance crossing the midline is extremely rare, which has not been reported yet. Here we report a distinctive case of mural unicystic ameloblastoma of mandible in a 17-year- old- girl with the radiographic presentation as mentioned above.

El ameloblastoma es un tumor odontogénico benigno que frecuentemente afecta a la mandíbula. El término ameloblastoma incluye varias características clínico-radiológicas y tipos histológicos. Aparte de los modelos clínicopatológicos que se encuentran con frecuencia existen algunas variantes, cuyo perfil biológico es desconocido o aún no elucidado. La razón de la falta de comprensión es la escasez de informes de casos publicados en la literatura. Entre los tipos, el ameloblastoma uniquístico es el menos frecuente y puede presentarse como una radiolucidez unilocular o multilocular, pero la peculiar presentación radiográfica de radiolucidez multilocular en el posterior de la mandíbula con aspecto radiográfico unilocular que cruza la línea mediana es extremadamente rara, y aún no se ha reportado. Se presenta un caso de ameloblastoma uniquístico mural de la mandíbula en una paciente de 17 años con la presentación radiográfica anteriormente descrita.

The histopathological examination of the dental follicleof asymptomatic impacted tooth: is it necessary? / Exame histopatológico do folículo dental de denteimpactado assintomático: é necessário?

Introduction: During the development of a tooth, the pericoronal tissue may develop pathological changes.The clinical dilemma occurs in the early diagnostic of the tissue around the crown of an uneruptedtooth. Objective: The purpose of this paper is to present a clinical case with different diagnoses of a smallradiolucency area around the crown of impacted teeth on the same patient. The histological diagnosis ofthe follicle related to tooth 48 was of dentigerous cyst and the histological finding of follicular tissue associatedto tooth 38 showed some features of unicystic ameloblastoma. The follicles of teeth 18 and 28 didnot present histopathological changes. Conclusion: The radiographic appearance may not be a reliableindicator of the absence of disease in pericoronal tissues. We recommend histopathological analysis onall surgically extracted follicle tissue, even when radiographic and clinical findings are not indicative ofpathological alterations.

Introdução: Durante o desenvolvimento dental, o tecido pericoronário pode sofrer alterações patológicas.O dilema clínico está no diagnóstico precoce dos tecidos em torno da coroa de um dente retido. Objetivo: O objetivodeste trabalho é apresentar um caso clínico em que houve diferentes diagnósticos histológicos relacionadosaos tecidos pericoronários em um mesmo paciente sem a presença de alteração radiográfica característica.Os diagnósticos histológicos dos folículos dos terceiros molares sugeriram cisto dentígero relacionado ao dente48, características de ameloblastoma unicístico ao dente 38, e os tecidos dos dentes 18 e 28 não apresentaramalterações histopatológicas. Conclusão: O aspecto radiográfico neste caso não foi um indicador confiável daausência de doença em tecidos pericoronários. Logo, recomendamos que todos os tecidos pericoronários sejamencaminhados para o exame histopatológico mesmo que os achados radiológicos e clínicos não mostrem alteraçõespatológicas.