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.

Estrogen Receptor, Progesterone Receptor, and HER-2 Expression in Recurrent Pleomorphic Adenoma.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm and, although mostly benign, recurrences, being called recurrent pleomorphic adenoma (RPA) and malignant transformation to carcinoma ex pleomorphic adenoma (CXPA), do occur. Recently, attention has been focused on molecular targeted cancer therapy in various tumors, including salivary gland tumors. The aim of this study was to investigate the role of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) in PA, RPA, and CXPA. In total, 20 cases of PA, 18 of RPA, and 7 cases of CXPA were immunohistochemically studied for ER, PR, and HER-2. For evaluation of ER and PR, only nuclear expression and greater than 10% positive cells were regarded as cutoff criteria. HER-2 was evaluated semiquantitatively and graded from 0 to 3+. HER-2 amplification was assessed by chromogenic in situ hybridization (CISH). Tumors were negative for ER, PR, and HER-2 in all cases of PA and RPA. A case of CXPA showed moderate and complete membranous staining, and 6 cases were negative. HER-2 amplification was not observed in any case. In conclusion, the lack of ER, PR, and HER-2 expression in PA, RPA, and CXPA suggests that these proteins are not involved in progression, recurrence, or malignant transformation of PA.

The Challenging Diagnosis of Primordial Odontogenic Tumor.

Primordial odontogenic tumor (POT) is a benign mixed odontogenic tumor comprised of a loose connective tissue with a similar morphology with dental papilla and exhibiting in its periphery the presence of a columnar epithelium. POT occurs in young patients and typically is associated with an unerupted tooth, with the mandible being the main anatomic site of occurrence. The present manuscript is aimed at describing a new case of POT and reviewing the main biologic findings related to this odontogenic tumor.

Can non-collagenous proteins be employed for the differential diagnosis among fibrous dysplasia, cemento-osseous dysplasia and cemento-ossifying fibroma?

Differential diagnosis among fibrous dysplasias, cemento-ossifying fibromas and cemento-osseous dysplasias is difficult, since there is considerable overlap of histologic features, but also extremely important, since they differ greatly in etiology, clinical behaviour, prognosis and terapeuthic approach. There is no data about the use of immunohistochemistry, a viable and accessible technique, for this purpose. The objective of this study was to investigate, comparatively, the immunohistochemical expression of major non-collagenous proteins (osteonectin [ON], osteopontin [OP], bone sialoprotein [BSP] and osteocalcin [OC]) of mineralized tissue extracellular matrix in 22 cases of fibrous dysplasias, 16 of cemento-ossifying fibromas and 16 of cemento-osseous dysplasias. ON maintained the same expression profile in all cases; the staining for OP was negative in fusiform cells producing cementoid globules and weak, as well as heterogeneous, in high mineralized matrixes; there was negativity for BSP in cementoid globules and in the fusiform cells that produce them, differently from the strong positive expression found in the majority of bone trabeculae and their peripheral cuboidal osteoblasts; and finally, the immuno-reactivity for OC was weak, except in cuboidal osteoblasts and osteocytes. We can conclude that the nature of mineralized structure and the cellular phenotype are much more responsible for variability in immunohistochemical profile than the type of lesion (fibrous dysplasias, cemento-ossifying fibromas and cemento-osseous dysplasias) which makes difficult, at least for a while, the use of these proteins with diagnosis purpose.

Benign odontogenic ghost cell lesions revisited and new considerations on dysplastic dentin.

OBJECTIVES: This study aimed to revisit benign odontogenic ghost cell lesions (BOGCL) by hematoxylin and eosin staining and immunohistochemistry. MATERIALS AND METHODS: Thirty cases of calcifying odontogenic cyst (COC) and 6 cases of dentinogenic ghost cell tumor (DGCT) were selected for histopathological and immunohistochemical analysis. Sections stained for cytokeratin (K) 14, K-19, amelogenin, collagen type 1 (COL-1), and dentin matrix acidic phosphoprotein 1 (DMP-1) were evaluated using qualitative analysis. Sections stained for Ki-67 and minichromosome maintenance protein-2 (MCM-2) were evaluated using semi-quantitative analysis. RESULTS: A morphologic overlap was noticed in all BOGCL. Moreover, no differences were detected in the expression of K-14 and K-19. The expression of proliferative markers Ki-67 and MCM-2 was similar between cystic and tumor lesions (p > .05). The presence of COL-1 and absence of amelogenin in the so-called dysplastic dentin, associated with its histologic pattern, suggest that this is in fact an enameloid-like tissue. CONCLUSIONS: The dysplastic dentin should be considered an enameloid-like tissue in these lesions. CLINICAL RELEVANCE: The similarity in histology, protein expression, and proliferative marker indices between COC and DGCT suggest that they are a sole entity and likely represent types of the same neoplasia.

Role of apoptotic, autophagic and senescence pathways in minor salivary gland adenoid cystic carcinoma.

BACKGROUND: Adenoid cystic carcinoma (ACC) is a salivary gland malignancy with poor long-term survival, which warrants studies aimed at clarifying the pathogenesis of this disease in order to widen the scope of therapeutic options currently available. Alterations in regulatory mechanisms relating to vascular support, cell death and autophagy are important pathways for tumor growth in cancer. Thus, the present study aimed to access vascular supply, apoptosis, autophagy and cell senescence in ACC of minor salivary glands. METHODS: We analyzed 25 cases of minor salivary gland ACC by immunohistochemistry using anti-CD34, anti-CD105, anti-D2-40, anti-Bax, anti-Bcl-2, anti-Beclin-1, anti-LC3B, anti-p21 and anti-p16. RESULTS: Microvessel density was low and based on anti-CD34, anti-CD105 and anti-D2-40 immunostaining. There was positivity for anti-CD34, anti-Bcl-2, anti-Beclin, anti-LC3B and anti-p21 and a positive correlation between Bcl-2 and Beclin (p = 0.014). CONCLUSIONS: Our results showed that ACC does not depend on neo-angiogenesis and is probably associated to anti-apoptotic, autophagic and anti-senescence events.

Comparison of p63/p40 Expression With Myoepithelial Markers in Minor Salivary Gland Tumors.

The present study aimed to compare the expression of p63/p40 with smooth muscle actin (SMA) and vimentin (VIM) by myoepithelial cells in minor salivary gland tumors. Fifty-two formalin-fixed paraffin-embedded samples of minor salivary gland tumors derived from intercalated duct (pleomorphic adenoma [PA], adenoid cystic carcinoma [ACC], epithelial-myoepithelial carcinoma [EMC], polymorphous adenocarcinoma [PAC], and secretory carcinoma [SC]) and 3 samples of minor salivary gland tumors derived from excretory duct (mucoepidermoid carcinoma [MEC]) were evaluated by means of immunohistochemistry. The data were analyzed qualitatively. The results indicated that p63 and p40 expression were detected in myoepithelial cells present in PA, ACC, and EMC. However, both proteins were also observed in squamous areas of PA and all cases of MEC. SMA were noticed in some myoepithelial cells of PA, ACC, and EMC. Expression of SMA was negative in the other salivary gland tumors evaluated. VIM was constantly expressed by myoepithelial cells in PA, ACC, and EMC. VIM was also observed in cells of PAC and SC, but not in squamous areas of PA and MEC. In conclusion, p63 expression is almost comparable with VIM in detecting myoepithelial cells, an immunolabeling pattern not followed by p40, and consequently, caution has to be taken during the interpretation of salivary gland tumor exhibiting an p63/p40 phenotype in order to avoid a misdiagnosis.

Microvessel density and cell proliferation in juvenile ossifying fibroma: A comparative study with central ossifying fibroma.

Considered as an aggressive counterpart of central ossifying fibroma (OF), juvenile ossifying fibroma (JOF) is a benign fibro-osseous neoplasm characterized by an unpredictable destructive behavior, elevated morbidity, mutilating treatment and high potential for local recurrences. The aim of this study is to compare the analysis for cell proliferation and vascular markers between JOF and OF. Cell proliferation index was measured by Ki-67 and Mcm-2 expression and microvessel density (MVD) was obtained by the immunoexpression of CD34/CD105. We observed a reduced expression of vascular markers, where MVD for CD34 was significantly higher in JOF than in OF (p = 0.009), but no statistical difference was found for CD105. JOF and OF showed low expression for Ki-67 and Mcm-2 and no difference was noted between both, suggesting that other mechanisms such as anti-apoptotic and/or pro-autophagic pathways or even increased expression of matrix metalloproteinases may be responsible for the aggressiveness of JOF.

Effect of epithelial growth factor on matrix metalloproteinase-2 and E-cadherin/ß-catenin expression in an in situ model of tumorigenesis.

The aim of the present study was to analyze the in vitro effect of various doses of epidermal growth factor (EGF; 5 and 10 ng/ml) on matrix metalloproteinase-2 (MMP-2) secretion and E-cadherin/ß-catenin expression by co-cultured cells that mimic an in situ carcinoma ex-pleomorphic adenoma, where benign myoepithelial cells from a pleomorphic adenoma surround malignant epithelial cells. EGF was supplemented in various doses and the effects were evaluated following four days of cell culture. ELISA was performed to determine MMP-2 secretion levels. Gene expression for E-cadherin and ß-catenin was analyzed using quantitative polymerase chain reaction. The results revealed that E-cadherin expression decreased when the cells were supplemented with 5 ng/ml EGF. ELISA results indicated that MMP-2 secretion increased when EGF was supplemented at concentrations of 5 and 10 ng/ml. The present findings demonstrated that EGF may be involved in the epithelial-mesenchymal transition process via altering the E-cadherin/ß-catenin complex and increasing MMP-2 secretion, which may then favor the dissolution of the basement membrane to the benefit of malignant cell clusters, contributing to the development of an invasive phenotype in this in vitro model of tumorigenesis.

Use of botulinum toxin type a in temporomandibular disorder / Utilização da toxina botulínica tipo a na disfunção temporomandibular

ABSTRACT Temporomandibular disorder (TMD) may be defined as a set of clinical scenarios involving the masticatory muscles, the temporomandibular joint (TMJ) and associated structures. Currently, 40 to 75% of the population has some sign of temporomandibular disorder, mainly pain located in the muscles of mastication in the pre-auricular region. The present clinical case was diagnosed as muscle temporomandibular disorder secondary to parafunction, as well as muscle hyperactivity due to surgical displacement of the left temporal muscle on two occasions, one for placement of aneurysm clips and the other for tumor excision from the supraorbital region on the left side. The patient sought medical and dental attention for 10 years due to constant headaches, tiredness and pain in the cheeks. The patient tried numerous bite-guards and pharmacological therapies to no avail. The American Academy of Orofacial Pain Questionnaire was applied combined with the Criteria for Research and Diagnostics (DRC) and a decision was made to use botulinum toxin type A in the masseter and temporalis muscles. An analog pain scale was applied over 90 days. Three days following the application of botulinum toxin type A, the patient reported a significant improvement with complete resolution of pain (level 0) after 90 days. At 12 weeks from starting treatment, facial muscle physiotherapy was introduced to strengthen the muscles of mastication and the patient remained pain-free, which allowed the preparation and adaptation of a snap-on prosthetic appliance. In conclusion, the use of botulinum toxin in patients with temporomandibular disorder should be considered as a viable therapeutic option.

RESUMO A desordem temporomandibular pode ser definida como um conjunto de distúrbios que envolvem os músculos mastigatórios, a articulação temporomandibular e estruturas associadas. Atualmente entre 40 a 75% da população apresenta algum sinal de desordem temporomandibular, sendo o mais frequente a dor, principalmente localizada nos músculos da mastigação e na região pré-auricular. O caso clínico apresentado foi diagnosticado como desordem temporomandibular muscular por parafunção, hiperatividade muscular antecedida por deslocamento do músculo temporal esquerdo para realização de duas cirurgias, uma para colocação de clips aneurismático e a outra para remoção de um tumor na região supraorbitária do lado esquerdo. A paciente procurou durante 10 anos ajuda médica e odontológica por sofrer com constantes dores de cabeça, cansaço, dor nas bochechas, usou inúmeras placas, medicamentos, porém o efeito desejado nunca fora alcançado. Frente ao histórico foi aplicado o questionário da Academia Americana de Dor Orofacial e o Critério de Pesquisa e Diagnóstico (RDC), e a conduta clinica adotada foi à aplicação de toxina botulínica tipo A nos músculos masseter e temporal. Foi aplicada uma escala de dor analógica ao longo de 90 dias. Já após 3 dias da aplicação da toxina botulínica tipo A, a paciente relatou melhora significativa chegando a nível 0 de dor após 90 dias. Após 12 semanas do início do tratamento, foram acrescidos exercícios para fortalecimento dos músculos da mastigação, sendo que a paciente continuava sem dor, permitindo desta forma a confecção e instalação de prótese tipo Snap-on. Desta forma, o emprego da toxina botulínica em pacientes com desordem temporomandibular deve ser considerado como uma boa opção terapêutica.

Factors that may influence polymorphous low-grade adenocarcinoma growth.

There is mounting evidence on the importance of some biological processes in tumor growth, such as vascular supply, apoptosis, autophagy, and senescence. We have investigated these processes in polymorphous low-grade adenocarcinoma (PLGA), in an attempt to identify those that are relevant for this particular lesion. We analyzed 31 cases of PLGA using immunohistochemistry to antibodies against CD34 and CD105 to detect blood vessels; against D2-40 to detect lymphatic vessels; against Bax, Bcl-2, and survivin to explore cell apoptosis; and against Beclin and LCB3 to investigate autophagy and against p21 and p16 to assess senescence. Our results showed that PLGA growth does not depend on newly formed vessels but only on preexisting vasculature. Furthermore, PLGA is promoted by autophagy, sustained by both anti-apoptotic and anti-senescence signals, and stimulated by Bcl-2 and survivin.

Estudo in vitro do padrão de crescimento e proliferação celular de pré-osteoblastos humanos com bio-oss® e genox® / In vitro study of growth and proliferation of human pre-osteoblast on bio-oss® and genox®

Objetivo: O presente trabalho avaliou o padrão de crescimento, o índice de proliferação celular e morfologia de pré-osteoblastos humanos cultivados com Bio-Oss® e GenOx®. Material e Método: Pré-osteoblastos humanos MC3T3-E1 foram cultivados em contato com os biomateriais por 1, 24 e 72horas para avaliação da proliferação celular, medido com o teste colorimétrico MTS. Para a avaliação do padrão de crescimento e da morfologia celular, as células foram cultivadas por 24 e 72 horas, respectivamente e avaliadas sob microscopia de contraste de fase e microscopia eletrônica de varredura (MEV). Para verificação de diferenças no crescimento celular entre os grupos foi utilizado o teste one-way de ANOVA, sendo considerados significantes valores de p<0,05. Resultados: A proliferação celular foi maior na primeira hora nas amostras em contato com os biomateriais em comparação ao grupo controle. Nos períodos de 24 e 72 horas de cultivo celular, a curva de crescimento não mostrou diferença estatisticamente significante entre os grupos (p>0.05). Na microscopia de contraste de fase observou-se que as células cresceram em proximidade aos biomateriais, iniciando a formação da monocamada de maneira semelhante. Quando analisadas no MEV, as células cultivadas sobre os biomateriais apresentaram-se com formato fusiforme e núcleo arredado. Conclusão: Com a comparação do comportamento biológico de Bio-Oss® e GenOx®, realizada in vitro neste estudo, pôde-se observar que apesar das diferenças físico-químicas, o padrão, índice de crescimento e morfologia celular de Bio-Oss® e GenOx® se mostraram semelhantes, e que ambos materiais são biocompatíveis e representam uma boa opção como substitutos ósseos.

Objective: The present study aimed to evaluate the growth pattern, cell proliferation index and morphology of human preosteoblasts cultured with Bio-Oss® and GenOx®. Material and Methods: MC3T3-E1 human pre-osteoblasts were cultured in contact with biomaterials for 1, 24 and 72 hours for the cell proliferation assay with the colorimetric test MTS. For the growth pattern and cell morphology analysis, the cells were cultured for 24 and 72 hours, respectively, and evaluated under phase contrast microscopy and scanning electron microscopy. To verify differences in cell growth among the groups, the one-way ANOVA test was used (p <0.05). Results: In the first hour of cell culture the cell proliferation was pronounced in samples in contact with the biomaterials. At 24 and 72 hours of cell culture, no significant differences between the groups was observed in respect of cell proliferation. In phase contrast microscopy it was noted that the cells grew in proximity to the biomaterials, initiating the formation of a monolayer. When analyzed in the scanning electron microscopy, the cells cultured on the biomaterials presented a fusiform morphology and a round nucleus. Conclusion: Despite the physico-chemical differences between Bio- Oss® and GenOx®, these two biomaterials presented a similar growth index and cell morphology analysis, showing that both biomaterials are biocompatible and represent a good choice as bone substitutes.

Mammaglobin and DOG-1 expression in polymorphous low-grade adenocarcinoma: an appraisal of its origin and morphology.

BACKGROUND: Polymorphous low-grade adenocarcinoma (PLGA) remains a diagnostic challenge for most pathologists due to its large spectrum of histological patterns. In this study, the expression of two new markers recently described for salivary gland tumors was studied in PLGA. METHODS: The morphology of 33 cases of PLGA was carefully evaluated using hematoxylin-and-eosin-stained sections and confirmed by immunohistochemistry for cytokeratin 7, vimentin, and S-100. Periodic acid-Schiff with diastase digestion was also used. The expression of mammaglobin and DOG-1 was carried out using the EnVision System. Mammaglobin was assessed according to the percentage of positively stained tumor cells, while DOG-1 was evaluated according to its presence and site. For MCM-2 and Ki-67, markers of proliferation, the labeling index of cell nuclei positivity was evaluated using total cell number. The ETV6-NTRK3 fusion was examined by fluorescence in situ hybridization analysis. RESULTS: The histological patterns of the tumor were classified as lobular or non-lobular. For the non-lobular pattern, tubular, cribriform, glomeruliform, trabecular, and papillary patterns were observed. Mammaglobin was present in all PLGA cases, and its expression was stronger (P = 0.01) in the lobular than in the non-lobular pattern. The expression of DOG-1 was present in the apical portion and cytoplasm of the cells. Proliferation markers were low for all cases independent of histological pattern. CONCLUSIONS: Polymorphous low-grade adenocarcinoma has been confirmed to originate from the intercalated duct and to feature high expression of mammaglobin in its lobular pattern resembling that of mammary secretory analogue carcinoma, except for the ETV6 gene rearrangement.

Epidemiology and georeferencing of squamous cell carcinoma cases and their relationship with pesticides / Epidemiologia e georreferenciamento dos casos de carcinoma epidermóide de boca e sua relação com agrotóxicos

ABSTRACT Objective To assess the prevalence of epidermoid carcinoma cases, georeference their locations, and seek to correlate them to areas with higher agricultural production and use of pesticides. Methods This was a cross-sectional, descriptive and retrospective study conducted by searching the histopathological reports with confirmed diagnosis of epidermoid carcinoma of the mouth issued from August 2005 to December 2011 by the public oral pathology laboratory of the State of Mato Grosso, Brazil. Data were plotted with the IBM SPSS Statistics software and spatial analysis used the ArcGIS 10.1 software. Results There were a higher number of diagnoses in 2007 (26.6%); 99 cases (75%) of patients were male; 96 cases (72.8%) were patients aged between 41 and 70 years; and the cities of Cuiabá, Várzea Grande and Rondonópolis respectively showed the highest number of occurrences. Conclusion No relationship was found between the occurrence of cases of epidermoid carcinoma and the municipalities with high agricultural production and pesticide use.

RESUMO Objetivo Analisar a prevalência dos casos de carcinoma epidermóide e fazer seu georreferenciamento, buscando correlaciona-los às áreas de maior produção agrícola e utilização de agrotóxicos. Métodos Trata-se de um estudo transversal, descritivo e retrospectivo realizado por meio de pesquisa dos laudos histopatológicos com diagnóstico confirmado de carcinoma epidermóide de boca emitidos de agosto de 2005 a dezembro de 2011 pelo serviço de patologia bucal do laboratório público do Estado de Mato Grosso. Os dados foram tabulados com o software IBM SPSS Statistics e a análise espacial utilizou o software ArcGIS 10.1. Resultados Houve um maior número de diagnósticos no ano de 2007 (26,6%), 99 casos (75%) eram de pacientes do sexo masculino; 96 casos (72,8%) eram de pacientes na faixa etária compreendida entre 41 e 70 anos e os municípios de Cuiabá, Várzea Grande e Rondonópolis apresentam respectivamente o maior número de ocorrências. Conclusão Não foi encontrada relação entre a ocorrência dos casos de carcinoma epidermóide de boca e os municípios com grande produção agrícola e elevado uso de agrotóxicos.

Disposição dos Cirurgiões-Dentistas para identificar condições médicas em consultório odontológico / Dentists' willingness to identify medical conditions in a dental setting

Objetivo: As doenças crônicas não transmissíveis bem como a infecção pelo HIV e as hepatites virais representam hoje problemas de saúde importantes liderando as causas de mortes e causando grande gasto de dinheiro público. O objetivo desta pesquisa foi avaliar as atitudes e vontade de Cirurgiões- Dentistas brasileiros em relação a detecção de condições médicas em consultório odontológico, e comparar os resultados com pesquisa semelhante conduzida com Cirurgiões-Dentistas americanos. Material e métodos: Entrevistamos 323 Cirurgiões-Dentistas de São Paulo. O questionário anônimo avaliou a opinião e disposição dos Cirurgiões-Dentistas em realizar procedimentos médicos no consultório odontológico. A escala de respostas de 5 pontos incluía 1 (muito importante/ muito disposto) até 5 (muito pouco importante/ muito pouco disposto). Resultados: Igualmente aos Cirurgiões-Dentistas americanos, a maioria dos entrevistados acredita ser muito importante detectar doença cardiovascular (80.8%), hipertensão (83.3%), diabetes (83.3%), infecção pelo HIV (86%), e hepatite (86.7%). A maioria está disposta a realizar exame com resultado imediato (54% dos Cirurgiões-Dentistas), mas apenas 47% estão dispostos a discutir o resultado de exames com o paciente imediatamente após realizá-lo. Menos da metade dos entrevistados (47%) consideram seguro saúde como "muito importante" na decisão de incorporar ou não os exames médicos no consultório. Tempo, custo, responsabilidade legal e a vontade do paciente foram considerados "muito importantes" pela maioria dos entrevistados. Conclusão: A maioria dos Cirurgiões-Dentistas brasileiros entrevistados acredita que a triagem para condições médicas em cadeira odontológica seja muito importante e estão dispostos a conduzir um rastreio para condições médicas específicas em consultório odontológico..

Objective: Non-communicable diseases as well as HIV infection and viral hepatitis represents today a major health problem leading causes of death and great expenditures for society. The objective of this survey was to assess Brazilians dentists' attitudes and willingness regarding chairside medical screening in the dental office, and compare the results with a similar survey conducted with American dentists. Material and methods: We interviewed 323 dentists from São Paulo city. The anonymous questionnaire aimed assessing the opinions of dentists in relation to medical procedures in the dental office. The 5-point response scale enclose 1 (very important/very willing) to 5 (very unimportant/very unwilling). Results: In the same way as the American dentists, the majority of the respondents believed it is very important for dentists to conduct screening for cardiovascular disease (80.8%), hypertension (83.3%), diabetes (83.3%), human immunodeficiency virus (86%), and hepatitis (86.7%). Most are willing to conduct screening that generated immediate results (54%), but only 47% are disposed to discuss results immediately with the patient during the dental visit. Less than half of interviewed dentists (47%) considered that having insurance coverage was "very important" in deciding whether or not incorporating medical screening into dental practice. Time, cost, liability and patient´s willing were considered more important among majority of the respondents. Conclusion: Most respondents believed that chair side screening for medical conditions was very important and were disposed to conduct screening for specified medical conditions in a dental setting.

Analysis of the mental foramen using cone beam computerized tomography / Análise do forame mentual em tomografias computadorizadas de feixe cônico

Introduction: Knowledge of the anatomical structures located in the region between the mental foramina is of critical importance in pre-operative planning. Objective: To evaluate the position of the mental foramen relative to the apices of the teeth and the distance to the edges of the mandible, using cone beam computerized tomography. Material and method: One hundred cone beam computerized tomographs of the mandible were evaluated; the tomographs were taken using a single tomographic device. Each image chosen was evaluated repeatedly from both sides of the mandible, the position of the mental foramen, indicating the region in which the foramen was found and the measures of the mental foramen, the lingual cortex and the mandibular base. Initially, the data were analyzed descriptively. A value of p<0.05 was chosen as the level of significance. Result: Forty-two percent of the mental foramina were located in the apex of the second pre-molar. The lingual margin of the mental foramen was located, on average, 3.1mm from the lingual cortex. The lower margin of the mental foramen was located 7.25 mm above the lower edge of the mandible. Conclusion: The mental foramen was located more frequently at a level of the apices of the second pre-molars, with a distance to the lingual cortex, on average, of 3.1mm and to the base of the mandible, on average, of 7.25 mm.

Introdução: O conhecimento das estruturas anatômicas localizadas na região entre os forames mentuais é de importância crucial nos planejamento pré-operatórios. Objetivo: Avaliar a posição do forame mentual relacionado aos ápices dos dentes, sua distância aos bordos da mandíbula com uso da tomografia computadorizada de feixe cônico. Material e método: Foram avaliadas 100 tomografias computadorizadas de feixe cônico da mandíbula realizada num único aparelho de tomografia. Cada imagem escolhida foi avaliada de forma repetida para ambos os lados da mandíbula, a posição do forame mentual, indicando a região em que o forame se encontrava e as medidas do forame mentual a cortical lingual e base da mandíbula. Os dados foram analisados inicialmente de forma descritiva. Um valor de p<0,05 foi escolhido como o nível de significância. Resultado: 42% dos forames mentuais estavam localizados no ápice do segundo pré-molar. A margem lingual do forame mentual localizou-se em média de 3,1 mm a partir da cortical lingual. A margem inferior do forame mentual foi localizada 7,25 mm acima da borda inferior da mandíbula. Conclusão: O forame mentual localizou-se com maior frequência em nível dos ápices dos segundos pré-molares, com distância à cortical lingual, em média, de 3,1 mm e base da mandíbula, em média, de 7,25 mm.

Dysregulation of the Rb pathway in recurrent pleomorphic adenoma of the salivary glands.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm, and while mostly benign, recurrences (RPA) and malignant transformation to carcinoma ex-PA (CXPA) do occur. Cell cycle proteins important in its tumorigenesis have been studied as markers for PA with a high risk of RPA or CXPA. The aim of the present study was to investigate cell cycle markers p-16, cyclin D1, CDK4, E2F, and retinoblastoma (Rb) in this context. Expression of p16, cyclin D1, E2F, CDK4, and Rb was studied by immunohistochemistry in 24 cases of PA, 21 of RPA, and 2 of CXPA. The presence of HPV was assessed by in situ hybridization. Immunostaining for p16 and cyclin D1 was negative or weakly positive in most cases of PA while strongly positive in the majority of RPA and both CXPA cases. Staining for Rb and CDK4 was either negative or weakly positive in PA, RPA, and CXPA. Expression of E2F was stronger in RPA and CXPA than in PA. Nuclear reactivity for HPV was not observed in any case. In conclusion, the strong staining for p16, cyclinD1, and E2F in RPA and CXPA, while weak or negative in PA, suggests that these proteins might be involved in recurrence and malignant transformation of PA.

How do benign myoepithelial cells from in situ areas of carcinoma ex-pleomorphic adenoma favor tumor progression?

In this brief commentary, we have shown how the benign myoepithelial cells from in situ areas of carcinoma ex-pleomorphic adenoma from salivary gland can favor tumor progression, not only dying by autophagy/senescence phenomena, disrupting the physical barrier, but also providing fuel for tumor progression.

Cellular senescence and autophagy of myoepithelial cells are involved in the progression of in situ areas of carcinoma ex-pleomorphic adenoma to invasive carcinoma. An in vitro model.

During tumor invasion, benign myoepithelial cells of carcinoma ex-pleomorphic adenoma (CXPA) surround malignant epithelial cells and disappear. The mechanisms involved in the death and disappearance of these myoepithelial cells were investigated via analysis of the expression of regulatory proteins for apoptosis, autophagy and cellular senescence in an in situ in vitro model. Protein expression relating to apoptosis (Bax, Bcl-2, Survivin), autophagy (Beclin-1, LC3B) and cellular senescence (p21, p16) was evaluated using indirect immunofluorescence. ß-galactosidase expression was assessed via histochemistry. Biopsies of CXPA (ex vivo) allowed immunhistochemical evaluation of p21 and p16, whilst LC3B, p21 and p16 protein expression was analyzed by western blotting. In the in vitro model, the myoepithelial cells were positive for LC3B (cytoplasm) and p21 (nucleus), whilst in vivo positivity for p21 and p16 was observed. In vitro, ß-galactosidase activity increased in the myoepithelial cells over time. Western blotting analysis revealed an increased LC3B, p16 and p21 expression in the myoepithelial cells with previous contact with the malignant cells when compared with those without contact. The investigation of behavior of benign myoepithelial cells in ductal areas of CXAP revealed that the myoepithelial cells are involved in the autophagy-senescence phenotype that subsequently leads to their disappearance.