Clinicopathologic and imaging features of odontogenic myxomas: a multi-institutional study.

PURPOSE: This study aims to report clinicopathologic and imaging features of odontogenic myxomas (OM), highlighting uncommon findings. METHODS: Clinicopathologic and imaging data of OMs diagnosed in the five Brazilian diagnostic pathology centers were collected and analyzed. RESULTS: The series comprised 42 females (68.9%) and 19 males (31.1%), with a 2.2:1 female-to-male ratio and a mean age of 34.5±15.4 years (range: 4-80). Clinically, most OMs presented as painless intraoral swelling (n = 36; 70.6%) in the mandible (n=37; 59.7%). Multilocular lesions (n=30; 83.3%) were more common than unilocular lesions (n=6; 16.7%). There was no statistically significant difference between the average size of unilocular and multilocular OMs (p=0.2431). The borders of OMs were mainly well-defined (n=24; 66.7%) with different degrees of cortication. Only seven tumors caused tooth resorption (15.9%), while 24 (54.5%) caused tooth displacement. Cortical bone perforation was observed in 12 (38.7%) cases. Morphologically, OMs were characterized mainly by stellate or spindle-shaped cells in a myxoid background (n=53; 85.5%). Surgical resection was the most common treatment modality (n=15; 65.2%), followed by conservative surgery (n=8; 34.8%). Outcomes were available in 20 cases (32.3%). Seven of these patients had local recurrence (35%). Enucleation was the treatment with the highest recurrence rate (4/7; 57.1%). CONCLUSIONS: OM has a predilection for the posterior region of the jaws of female adults. Despite their bland morphological appearance, they displayed diverse imaging features. Clinicians must include the OM in the differential diagnosis of osteolytic lesions of the jaws. A long follow-up is needed to monitor possible recurrences.

Odontogenic Myxoma: Systematic review and bias analysis.

BACKGROUND: Odontogenic myxoma (OM) is a rare neoplasm, which originates from odontogenic ectomesenchyme. There is no study in the literature that analyses the best standards for OM diagnosis and how the treatment modalities may influence the recurrence rates. OBJECTIVE: To evaluate the best standards for odontogenic myxoma (OM) diagnosis and treatment, and how these may influence the recurrence rates. STUDY DESIGN: Two independent researchers performed a systematic review in many databases. Fifty-two eligible studies were included for qualitative analysis. Bias analysis was conducted according to Oxford Centre for Evidence-Based Medicine. RESULTS: A total of 1363 OM cases were reported on, and female gender with average age of 27 years is the most common patient profile. Conventional microscopic findings were observed in 93.43% of the reported cases. In 57.49% of the cases, multilocular radiographic appearance was present, followed by unilocular appearance (32.87%). Posterior mandible was the site with the major prevalence, while surgical resection was the most common treatment modality, followed by enucleation. Recurrence rates for both treatment modalities were approximately close (13.04% and 25.0%, respectively). CONCLUSION: The correct diagnosis of OM relies on the association of clinical, radiographic and microscopic findings. About imaging examinations, panoramic radiography and computed tomography are sufficient for the evaluation of OM. Recurrence rates were closely among the two most used surgery treatments. So according to some clinical-radiological aspects, conservative surgery may be preferred than aggressive surgery modalities.

Reconstrucción microquirúrgica de cabeza y cuello en paciente pediátrico / Micro-surgical reconstruction of the head and neck in a pediatric patient

OBJETIVO: Realizar un análisis retrospectivo de pacientes pediátricos sometidos a reconstrucciones con injertos libres microvasculares del territorio maxilofacial en el Hospital Luis Calvo Mackenna entre los años 2014 y 2018. MATERIALES Y MÉTODO: Se realizó un análisis de los casos reconstruidos entre los años indicados. RESULTADOS: Un total de 11 pacientes fueron incluidos en la muestra, 7 hombres y 4 mujeres. El rango de edad de los pacientes fue entre 3 a 17 años (media 10,1). Siete colgajos de fíbula, 3 dorsales y 1 anterolateral de muslo fueron utilizados para reconstrucción. La tasa de éxito de los colgajos fue de un 100%. Discusión: Se realizó una discusión de los colgajos y sus principales indicaciones en pediatría y se compararon los resultados de la revisión con los casos reportados. CONCLUSIÓN: El estudio preoperatorio, una adecuada planificación, la rehabilitación de la oclusión dentaria, la reconstrucción simétrica y mantener el contorno facial deben ser objetivos de la reconstrucción.

AIM: Carry out a retrospective analysis of pediatric patients undergoing reconstructions with free micro-vascular grafts of the maxillofacial territory at the Luis Calvo Mackenna Hospital during the years 2014 and 2018. MATERIALS AND METHOD: Retrospective analysis of the cases reconstructed during the years 2014 and 2018 was made. RESULTS: A total of 11 patients were included in the sample, 7 men and 4 women. The age range of the patients was between 3 to 17 years (mean 10.1 years) . Seven Fibula flaps, 3 dorsal and 1 anterolateral thigh flaps were used for reconstruction. The success rate of the flaps was 100%. DISCUSSION: A discussion of the flaps and their main indications in pediatrics was made and the results of the review were compared with the cases reported. CONCLUSION: The pre-operative study, adequate planning, the rehabilitation of the dental occlusion, the symmetry reconstruction and maintaining the facial contour must be objective of the reconstruction.

Melanotic neuroectodermal tumor of infancy of the jaw bones: Update on the factors influencing survival and recurrence.

The aim of the present study was to integrate the available data published on melanotic neuroectodermal tumor of infancy (MNTI) of the jaw bones. An electronic search was undertaken in April 2018. Hundred forty-seven publications and 371 patients were included. The lesion was more prevalent in males and in the second to sixth months of life. The lesions mostly presented as a rapidly growing bluish swelling and the most commonly involved was the anterior maxilla. The mean follow-up was 51.1 months (range 1-408 months). Age (P ≤ .0001), location (P = .007), occurrence of lymph node metastasis (P ≤ .0001), treatment (P = .001), recurrence (P ≤ .0001), and distant metastasis (P = .0001) were independently associated with survival. Recurrence was significantly correlated with age (P = .0001), distant metastasis (P = .0001), and treatment (P = .0001). Patients older than 12 months, with lesions in the mandible, positive regional lymph node metastasis, treated with chemotherapy, recurrence, or distant metastasis presented the worst prognosis.

Is conservative surgery a better choice for the solid/multicystic ameloblastoma than radical surgery regarding recurrence? A systematic review.

PURPOSE: Determine if conservative surgery of primary solid/multicystic ameloblastoma (SMA) is capable of decreasing the recurrence rate as effectively as radical surgery. METHODS: We searched in MEDLINE, Web of Science, Scopus and Cochrane Library for original studies reporting on the conservative or radical treatment of primary SMA and the related recurrence rate. All selected data were independently assessed. Meta-analysis was performed and the Relative Risk (RR) of recurrence with a confidence interval of 95% was the effect measure. P value for the summary effect of < 0.05 was considered statistically significant. RESULTS: The 2647 records retrieved were reduced to 7 studies to be qualitatively assessed and 4 studies were included in the meta-analysis. RR of 1.88 [0.59, 5.95] of the pooled values pointed that recurrence rate after the conservative surgery is neither comparable nor lower than the radical surgery (P = 0.28). CONCLUSIONS: Conservative surgery does not reduce the recurrence rate as efficiently as radical surgery for primary SMA. However, there is not enough evidence to support this statement.

Rehabilitation using immediate loading in patients with partial resection of the jaw

ABSTRACT: Ameloblastoma is a rare tumor that affects the maxillomandibular region. Surgical resection is often indicated, and oral rehabilitation becomes a challenge. This study aims to report on the mandibular rehabilitation with implant supported prosthesis using immediate loading with subsequent resection. A patient with a confirmed diagnosis of multicystic ameloblastoma in the left jaw underwent a partial resection of the mandible and a reconstruction with a titanium plate. After 2 years of follow-up with clinical examinations and imaging testing and with no signs of recurrence, the patient underwent the technique of immediate load implants, rehabilitating the mandible with an implant supported fixed prosthesis and the maxilla with a conventional complete denture. During the seven years of follow-up with the patient, there was no sign of recurrence of ameloblastoma. The rehabilitation with oral implants under immediate loading demonstrated to be successful, and the cemented cylinder technique used in this study coupled with passivity showed a favorable prognosis for the longevity of implants.

Rehabilitación clínica de un defecto maxilar / Clinical rehabilitation of a maxillary defect

Las pérdidas parciales o totales del maxilar y de otros tejidos vecinos crean grandes defectos, estableciendo una comunicación entre la cavidad bucal y nasal que comprometen la función y la estética, con impacto psicológico sobre la persona afectada, limitando sus posibilidades y disminuyendo su calidad de vida. Los defectos en la región maxilofacial pueden tener orígenes congénitos y adquiridos (traumáticos, oncológicos, patológicos u otros). La mayoría de los defectos maxilares tienen origen oncológico. El tratamiento quirúrgico de los tumores del maxilar, seno y fosas nasales, deja como secuela una pérdida de tejido de diferente magnitud. Las personas que han padecido este tipo de tratamiento quirúrgico deben ser rehabilitadas con una prótesis obturatriz. El objetivo de este trabajo fue presentar el caso clínico de una paciente con defecto maxilar de origen oncológico, rehabilitada con una prótesis obturatriz definitiva con bulbo obturador rígido, hueso.

Ceratoameloblastoma: uma lesão muito rara com recidiva incomum / Keratoameloblastoma: a very rare lesion with an unusual recurrence

A denominação ceratoameloblastoma tem sido utilizada para descrever um grupo histológico heterogêneo de variantes do ameloblastoma, que tem em comum a formação de ceratina pelo epitélio ameloblastomatoso. Até o momento, vinte casos foram previamente reportados na literautra, dos quais cinco exibem um componente papilifero. Nós relatamos um novo caso de um tumor recidivado que se enquadra no espectro do keratoameloblastoma, o qual apresentava uma lesão expansiva, sólida, com calcificações internas, na fossa infratemporal direita, seis anos após uma hemimandibulectomia ipsilateral, de uma mulher branca de 46 anos. Ilhas de células colunares que lembram ameloblastoma ao redor de uma área central com células estreladas, algumas das quais completamente preenchidas por ceratina e outras exibindo células basais colunares a cuboidais com núcleo hipercromático, foram observadas na avaliação histológica do espécime. Nós revisamos o padrão clínico, histopatológico e radiográfico dos casos previamente publicados de ceratoameloblastoma, além do tratamento e acompanhamento realizado. Embora um pequeno número de casos tenha sido reportado, o comportamento biológico agressivo e altas taxas de recorrência sugerem que um manejo mais agressivo deve ser realizado. Ressecção com margens de segurança e análise histopatológica dessas margens são altamente recomendadas. (AU)

The denomination keratoameloblastoma has been used to describe a histologically heterogeneous group of ameloblastoma variants which have in common the formation of keratin by the ameloblastomatous epithelium. Up to now twenty cases of keratoameloblastoma have been previously reported in the literature, of which five exhibited a papilliferous component. Here we report a new case of a relapsed tumor that fits the spectrum of keratoameloblastoma which presented as an expansile, solid lesion with internal calcification in the right infratemporal fossa six years after ipsilateral hemimandibulectomy of a 46- year-old white female. Islands of columnar cells resembling ameloblasts surrounding a central area with starry cells, some of them completely filled with keratin and others also showing columnar to cuboidal basal cells with hypercromatic nuclei were observed in the histological evaluation of the specimen. The clinical, histopathologic and radiographic features of keratoameloblastoma are reviewed so as treatment and follow up. Although only few cases have been reported, the biological aggressive behavior and the high recurrence suggest that a more aggressive approach should be performed. A resection with sufficient safety margins and histopathological analysis of surgical margins are highly recommended. (AU)

Necrosis óseas de los maxilares / Osteonecrosis of the jaws

Las necrosis óseas de los maxilares están representadas por una serie de procesos patológicos que tienen por denominador común la muerte isquémica de los elementos del hueso y la médula ósea. Los autores realizan una revisión de la literatura sobre el tema y presentan varios casos en los que esta enfermedad se halla presente, obedeciendo a diferentes efectores y estableciendo el tratamiento adecuado...

Colgajo miofascial de temporal en la reconstrucción de maxilar superior: informe de un caso / Temporal myofascial flap in the reconstruction of the maxilla: a case report

Objetivo: exponer las ventajas y desventajas del colgajo de músculo temporal en la reconstrucción del maxilar superior. Describir la técnica quirúrgica completa, desde el colgajo hemicoronal hasta la tunelización y fijación al maxilar contralateral. Caso clínico. Se trata de un paciente de 75 años con diangóstico de carcinoma espinocelular de la infraestructura del maxilar superior izquierdo. Se determina su resección y reconstrucción con colgajo de músculo temporal. Conclusión: para este fin, existe una gran cantidad de colgajos, como los colgajos a distancia, a pedicuro vascular y los microvascularizados. Estos últimos poseen la gran ventaja de transportar todos los tejidos necesarios, a diferencial del colgajo temporal. Pese a esto, el colgajo de temporal constituye una solución rápida, segura, estética y funcionalmente excelente para la reconstrucción del maxilar superior.

Colgajo miofascial de temporal en la reconstrucción de maxilar superior: informe de un caso / Temporal myofascial flap in the reconstruction of the maxilla: a case report

Objetivo: exponer las ventajas y desventajas del colgajo de músculo temporal en la reconstrucción del maxilar superior. Describir la técnica quirúrgica completa, desde el colgajo hemicoronal hasta la tunelización y fijación al maxilar contralateral. Caso clínico. Se trata de un paciente de 75 años con diangóstico de carcinoma espinocelular de la infraestructura del maxilar superior izquierdo. Se determina su resección y reconstrucción con colgajo de músculo temporal. Conclusión: para este fin, existe una gran cantidad de colgajos, como los colgajos a distancia, a pedicuro vascular y los microvascularizados. Estos últimos poseen la gran ventaja de transportar todos los tejidos necesarios, a diferencial del colgajo temporal. Pese a esto, el colgajo de temporal constituye una solución rápida, segura, estética y funcionalmente excelente para la reconstrucción del maxilar superior.(AU)

Ossifying Fibroma of the Jaws: A Clinicopathological Case Series Study

The aim of this study was to assess the clinical, radiographic and microscopic features of a case series of ossifying fibroma (OF) of the jaws. For the study, all cases with OF diagnosis from the files of the Oral Pathology Laboratory, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil, were reviewed. Clinical data were obtained from the patient files and the radiographic features were evaluated in each case. All cases were reviewed microscopically to confirm the diagnosis. Eight cases were identified, 5 in females and 3 in males. The mean age of the patients was 33.7 years and most lesions (7 cases) occurred in the mandible. Radiographically, all lesions appeared as unilocular images and most of them (5 cases) were of mixed type. The mean size of the tumor was 3.1 cm and 3 cases caused displacement of the involved teeth. Microscopically, all cases showed several bone-like mineralized areas, immersed in the cellular connective tissue. From the 8 cases, 5 underwent surgical excision and 1 patient refused treatment. In the remaining 2 cases, this information was not available. In conclusion, OF occurs more commonly in women in the fourth decade of life, frequently as a mixed radiographic image in the mandible. Coherent differential diagnoses are important to guide the most adequate clinical approach. A correlation between clinical, imaginological and histopathological features is the key to establish the correct diagnosis.

O objetivo deste estudo foi analisar as características clínico-radiográficas e microscópicas de uma série de casos de fibroma ossificante (FO). Para o estudo, todos os casos com diagnóstico de FO do arquivo do Laboratório de Patologia Bucal da Universidade de Ribeirão Preto, Ribeirão Preto, São Paulo, Brasil, foram estudados. Os dados clínicos foram coletados das fichas de encaminhamento das lesões ao Laboratório. As características radiográficas foram avaliadas em cada caso. Todos os casos foram revisados microscopicamente para confirmação do diagnóstico. Oito casos foram identificados, 5 em mulheres e 3 em homens. A idade média dos pacientes foi de 33,7 anos e a maioria das lesões (7 casos) ocorreu na mandíbula. Radiograficamente todas as lesões se apresentavam como imagens uniloculares e a maioria (5 casos) se mostravam como imagem mista. O tamanho médio do tumor foi de 3,1 cm e 3 casos causavam deslocamento dos dentes envolvidos. Microscopicamente, todos os casos apresentavam várias áreas mineralizadas semelhantes a osso, imersas em um tecido conjuntivo celularizado. Dos 8 casos, 5 foram submetidos a excisão cirúrgica da lesão e 1 paciente recusou tratamento. Nos outros 2 casos, essa informação não estava disponível. Conclui-se que o FOs ocorrem mais comumente na mandíbula de pacientes do gênero feminino durante a quarta década de vida e se apresentam frequentemente como uma imagem radiográfica mista. Diagnósticos diferenciais coerentes são importantes para guiar a conduta clínica mais adequada. A correlação entre as características clínicas, imaginológicas e histopatológicas é a chave para estabelecer o diagnóstico correto.

Ossifying fibroma of the jaws: a clinicopathological case series study.

The aim of this study was to assess the clinical, radiographic and microscopic features of a case series of ossifying fibroma (OF) of the jaws. For the study, all cases with OF diagnosis from the files of the Oral Pathology Laboratory, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil, were reviewed. Clinical data were obtained from the patient files and the radiographic features were evaluated in each case. All cases were reviewed microscopically to confirm the diagnosis. Eight cases were identified, 5 in females and 3 in males. The mean age of the patients was 33.7 years and most lesions (7 cases) occurred in the mandible. Radiographically, all lesions appeared as unilocular images and most of them (5 cases) were of mixed type. The mean size of the tumor was 3.1 cm and 3 cases caused displacement of the involved teeth. Microscopically, all cases showed several bone-like mineralized areas, immersed in the cellular connective tissue. From the 8 cases, 5 underwent surgical excision and 1 patient refused treatment. In the remaining 2 cases, this information was not available. In conclusion, OF occurs more commonly in women in the fourth decade of life, frequently as a mixed radiographic image in the mandible. Coherent differential diagnoses are important to guide the most adequate clinical approach. A correlation between clinical, imaginological and histopathological features is the key to establish the correct diagnosis.

Odontogenic keratocyst tumor: report of two cases / Tumor queratoquiste odontogénico: reporte de dos casos

In 2005, odontogenic cyst was classified as keratocyst odontogenic tumor due to being aggressive and recurrent. The keratocyst odontogenic tumor has characteristics, with slow development, does not cause metastases and provides great bone destruction. The aim of this study was to discuss the aspects regarding the diagnosis, prognosis and treatment of odontogenic keratocyst tumor, through the report of two cases. Both initially underwent decompression of the lesion present proximity of anatomical structures to be great and noble, aiming to prevent pathological fractures. We carried out the clinical-radiographic and after regression of the lesion, patients underwent enucleation total.

El año 2005 quiste odontogénico fue clasificado como un tumor queratoquiste odontogénico (TQO) debido a su agresividad y recurrencia. El TQO tiene las características del tumor: crecimiento lento, no causa metástasis y proporciona una gran destrucción ósea. El objetivo de este estudio fue examinar los aspectos relacionados con el diagnóstico, pronóstico y tratamiento del TQO mediante la presentación de dos casos. Ambos casos fueron inicialmente sometidos a descompresión debido al gran tamaño de la lesión y la proximidad de ésta con estructuras anatómicas importantes, con el objetivo de prevenir las fracturas patológicas. Se llevó a cabo un seguimiento clínico-radiográfico y después de tener una regresión de la lesión postdescompresión, los pacientes fueron sometidos la enucleación total.

Peripheral osteoma of the maxillofacial region: a study of 10 cases.

UNLABELLED: Peripheral osteoma is a benign neoplasm, with low recurrence rate. Its incidence is rare in the jaws and the mandible is more affected than the maxilla. In most cases it is discovered during routine radiographic examinations. OBJECTIVE: The aim of this study is to show the author's experience regarding the treatment of this neoplasm. METHODS: A retrospective study from January 2002 to December 2007 including ten cases of peripheral osteoma in the maxillofacial region which were treated surgically by removal of the lesion followed by histological confirmation. None of the cases were correlated with Gardner's syndrome. RESULTS: In this series the incidence of this neoplasm was higher in females (1.5:1) with a mean age of 39, without age preference. One of the patients had lesion recurrence two years after the first surgery, having been submitted to another intervention, with no signs of relapse after three years and six months of follow-up. CONCLUSION: Surgical treatment is effective for peripheral osteoma with a low recurrence rate.

Osteoma periférico da região maxilofacial: um estudo de 10 casos / Peripheral osteoma of the maxillofacial region: a study of 10 cases

Osteoma periférico é uma neoplasia benigna, com baixa taxa de recorrência. Sua incidência é rara nos maxilares e a mandíbula é mais afetada do que a maxila. Na maioria dos casos, é descoberto durante exames radiográficos de rotina. OBJETIVO: O objetivo deste trabalho é mostrar a experiência dos autores no tratamento desta neoplasia. MÉTODO: Em um estudo retrospectivo de janeiro de 2002 a dezembro de 2007 foram avaliados dez casos de osteoma periférico na região maxilofacial, tratados cirurgicamente por remoção completa da lesão, seguido de confirmação histológica. Nenhum dos casos estava correlacionado com a síndrome de Gardner. RESULTADOS: Nesta série avaliada, a incidência desta neoplasia foi maior no gênero feminino (1,5:1), com média de idade de 39 anos, sem predileção por faixa etária. Um dos pacientes apresentou recidiva da lesão após dois anos da primeira cirurgia, tendo sido submetido à nova intervenção, sem sinais de recidiva após três anos e seis meses de acompanhamento. CONCLUSÃO: O tratamento cirúrgico para o osteoma periférico é efetivo, com baixa taxa de recidiva.

Peripheral osteoma is a benign neoplasm, with low recurrence rate. Its incidence is rare in the jaws and the mandible is more affected than the maxilla. In most cases it is discovered during routine radiographic examinations. OBJECTIVE: The aim of this study is to show the author's experience regarding the treatment of this neoplasm. METHODS: A retrospective study from January 2002 to December 2007 including ten cases of peripheral osteoma in the maxillofacial region which were treated surgically by removal of the lesion followed by histological confirmation. None of the cases were correlated with Gardner's syndrome. RESULTS: In this series the incidence of this neoplasm was higher in females (1.5:1) with a mean age of 39, without age preference. One of the patients had lesion recurrence two years after the first surgery, having been submitted to another intervention, with no signs of relapse after three years and six months of follow-up. CONCLUSION: Surgical treatment is effective for peripheral osteoma with a low recurrence rate.

Ameloblastoma demographic, clinical and treatment study: analysis of 40 cases.

UNLABELLED: Dental lesions represent about 1% of oral cavity tumors being ameloblastoma the most common one. It is a tumor of epithelial origin that mainly affects the jaw, and less commonly the maxilla. Its clinical presentation is that of an asymptomatic slow-growing tumor. Despite being a benign tumor, it has an invasive behavior with a high rate of recurrence if not treated properly. OBJECTIVE: To describe the cases of ameloblastoma in a reference department. METHODS: Retrospective analysis of 40 cases. The variables analyzed were: age, gender, ethnicity, tumor location, type of treatment, complications and recurrence. RESULTS: The most affected gender was male - 21 cases (52.5%); with a predominance of Caucasians - 24 cases (60%). The mean age was 35.45 years; the most common location was in the jaw - 37 cases (92.5%). Facial asymmetry was the most frequent complaint. Of the 40 cases, 33 were submitted to surgery. Of those submitted to surgery, 24 (72.72%) underwent segmental resection, with recurrence in 4 (12.12%) cases. CONCLUSION: Ameloblastoma may relapse when treatment is not performed with broad surgical resection of the lesion with wide safety margins.

miR-15a/16-1 influences BCL2 expression in keratocystic odontogenic tumors.

BACKGROUND: A keratocystic odontogenic tumor (KCOT) is a benign destructive recurrent odontogenic cystic neoplasm. The microRNAs (miRNAs) miR-15a and miR-16-1 function as negative regulators of the anti-apoptotic gene BCL2 at the post-transcriptional level. Notably, high Bcl-2 immunoexpression is found in the epithelial lining of KCOTs, while the loss of Bcl-2 immunopositive cells is observed in marsupialized cysts. The purpose of this study was to investigate whether the transcription of miR-15a and miR-16-1 is altered in KCOTs and whether it is associated with BCL2 gene expression in such lesions. METHODS: Using qRT-PCR and immunohistochemical analyses, we examined miR-15a/16-1 and BCL2 gene expression in KCOTs. The impact of miR-15a/16-1 expression on BCL2 gene translation was investigated by in vitro studies using primary KCOT culture cells. RESULTS: Using qRT-PCR, we observed miR-15a and/or miR-16-1 downregulation in the majority of the KCOT samples (24 of 28). We also observed higher BCL2 mRNA expression in 19 of 20 KCOT frozen samples and moderate to high Bcl-2 immunopositivity in the basal layer cells of 16 of 18 paraffin embedded KCOTs (median: 42.6 %). In vitro over-expression of miR-15a/16-1 in human KCOT-1 primary cell cultures resulted in a decrease in Bcl-2 protein expression. Furthermore, all five paired KCOTs collected before and after marsupialization treatment exhibited an increase in miR-15a after the procedure. CONCLUSIONS: Our results suggest that KCOT neoplastic cells exhibit an anti-apoptotic profile that may be related to lower miR-15a/16-1 expression. Additionally, we demonstrated that miRNA expression increases after marsupialization, implicating an etiological and therapeutic role of miRNAs in KCOT.

Estudo demográfico, clínico e terapêutico do ameloblastoma: análise de 40 casos / Ameloblastoma demographic, clinical and treatment study: analysis of 40 cases

As lesões odontogênicas representam cerca de 1% dos tumores da cavidade bucal, sendo o ameloblastoma a afecção mais frequente. Trata-se de um tumor de origem epitelial, que afeta principalmente a mandíbula e, raramente, a maxila. Clinicamente, apresenta-se como tumor de crescimento lento, assintomático. Apesar de ser um tumor benigno, cursa com comportamento invasivo com alta taxa de recidiva, se não tratado adequadamente. OBJETIVO: Descrever os casos de ameloblastoma em serviço de referência. MÉTODOS: Análise retrospectiva de 40 casos. As variáveis analisadas foram: idade, gênero, etnia, localização do tumor, tipo de tratamento, complicação e recorrência. RESULTADOS: O gênero mais atingido foi o masculino, 21 casos (52,5%), com predomínio da etnia caucasiana - 24 casos (60%). A média de idade foi de 35,45 anos, a localização mais comum foi na mandíbula - 37 casos (92,5%). Assimetria facial a queixa mais frequente. Dos 40 casos, 33 foram submetidos a procedimento cirúrgico. Dos que tiveram tratamento cirúrgico, 24 (72,72%) foram submetidos à ressecção segmentar, com recidiva em quatro (12,12%) casos. CONCLUSÃO:O ameloblastoma apresenta possibilidade de recidiva quando o tratamento cirúrgico não é realizado com ressecção ampla da lesão com margens de segurança.

Dental lesions represent about 1% of oral cavity tumors being ameloblastoma the most common one. It is a tumor of epithelial origin that mainly affects the jaw, and less commonly the maxilla. Its clinical presentation is that of an asymptomatic slow-growing tumor. Despite being a benign tumor, it has an invasive behavior with a high rate of recurrence if not treated properly. OBJECTIVE: To describe the cases of ameloblastoma in a reference department. METHODS: Retrospective analysis of 40 cases. The variables analyzed were: age, gender, ethnicity, tumor location, type of treatment, complications and recurrence. RESULTS: The most affected gender was male - 21 cases (52.5%); with a predominance of Caucasians - 24 cases (60%). The mean age was 35.45 years; the most common location was in the jaw - 37 cases (92.5%). Facial asymmetry was the most frequent complaint. Of the 40 cases, 33 were submitted to surgery. Of those submitted to surgery, 24 (72.72%) underwent segmental resection, with recurrence in 4 (12.12%) cases. CONCLUSION:Ameloblastoma may relapse when treatment is not performed with broad surgical resection of the lesion with wide safety margins.

Different manifestations of calcifying cystic odontogenic tumor.

The calcifying cystic odontogenic tumor normally presents as a painless, slow-growing mass, involving both maxilla and mandible, primarily the anterior segment (incisor/canine area). It generally affects young adults in the third to fourth decades, with no gender predilection. Computerized tomography images revealed important characteristics that were not detected by panoramic radiography, such as fenestration, calcification and tooth-like structures. The typical microscopic feature of this lesion is the presence of variable amounts of aberrant epithelial cells, without nuclei, which are named "ghost cells". In addition, dysplastic dentine can be found and occasionally the cyst can be associated with an area of dental hard tissue formation resembling an odontoma. The treatment for calcifying cystic odontogenic tumor involves simple enucleation and curettage. The purpose of this article is to present two different manifestation of calcifying cystic odontogenic tumor in which computerized tomography, associated to clinical features, served as an important tool for diagnosis, adequate surgical planning and follow-up of patients.