E-learning as a strategy in dentistry in the context of COVID-19: a path to follow?

Abstract The current study aims to assess the effectiveness of e-learning in compliance with the new biosafety recommendations in dentistry in the context of COVID-19 applied to the clinical staff of a dental school in Brazil. A quasi-experimental epidemiological study was carried out by means of a structured, pre-tested online questionnaire, applied before and after an educational intervention, using an e-learning format. After data collection, statistical tests were performed. A total of 549 members of the clinical staff participated in the study in the two collection phases, with a return rate of 26.9%. After the e-learning stage, a reduction was found in the reported use of disposable gloves, protective goggles, and surgical masks. The course had no impact on the staff's knowledge concerning the proper sequence for donning PPE and showed 100% effectiveness regarding proper PPE doffing sequence. Knowledge about avoiding procedures that generate aerosols in the clinical setting was improved. Despite the low rate of return, it can be concluded that online intervention alone was ineffective in significantly improving learning about the new clinical biosafety guidelines. Therefore, the use of hybrid teaching and repetitive training is highly recommended.

Staff Knowledge and Attitudes Towards COVID-19 New Biosafety Practices at a Brazilian Dental School

ABSTRACT Objective To evaluate knowledge and attitudes towards biosafety recommendations during the COVID-19 pandemic at a Brazilian dental school. Material and Methods A cross-sectional study was performed in 2020 with the clinical staff of a Brazilian dental school. The whole clinical staff was sent pre-tested self-administered online questionnaires about knowledge and attitudes towards the recommendations for biosafety in dental settings in the context of the COVID-19 pandemic. Descriptive statistical analyses were carried out for proportion calculation. Results Disposable head covering caps, isolation gowns, and gloves were the most frequently reported personal protective equipment (PPE). The rates ranged from 52.9% to 88.5% for N95 respirators, from 68.6% to 92.6% for face shields, from 47.4% to 67.5% for conventional eye protection shields, and 45.1% to 77.4% for eye protection with solid side shields. Chlorhexidine gluconate was the most frequent mouthwash indicated before clinical dental care. The percentage of agreement to provide clinical care to patients with suspected COVID-19 varied from 23.5% to 50.0%. The percentage of respondents who agreed that bioaerosol-generating procedures should be avoided was higher than 74.5%. Less than 50% knew the correct sequence for doffing of PPE. Conclusion This study revealed important gaps in knowledge and attitudes towards prevention and control measures against infection in dental environments in the context of COVID-19, indicating the need for improvements.

Immunocompromised patients and coronavirus disease 2019: a review and recommendations for dental health care

Abstract In less than four months, an unprecedented pandemic changed the world scenario, closing institutions and commerce, paralyzing sports championships, blocking frontiers, and putting almost all populations in a house quarantine regimen. Immunocompromised patients are within the high-risk group to severe outcomes from COVID-19. However, there is no clear evidence of the association between impaired immune host status and complications from SARS-CoV-2 infection so far. The virus is transmitted by inhalation or direct contact with infected secretions, and therefore the dental office is a highly susceptible environment for such transmission. Here, we review the literature and discuss immunological COVID-19 related issues. We also make suggestions for immunocompromised patients' support in this new emerging context of clinical dental practice. Until comprehensive findings are published, individuals with impaired immunity should be considered as high-risk. Cross infection control procedures for the clinical care of immunocompromised patients should follow the same guidelines that are being proposed for immunocompetent ones. However, during the active outbreak, people under immunosuppressive conditions should not receive elective procedures, even if they do not have symptoms or exposure history to COVID-19, and in case of emergence, care must be done in a separate airborne room. In the pos-pandemic phase, the dental care general recommendations should be the same for all subjects. Changes in the current guidelines have been proposed to SARS-CoV-2 infection control in order to provide the best and safe dental practice. However, they still need to be validated by future studies.

DNA Methylation patterns of immune response-related genes in inflammatory external root resorption

Abstract Inflammatory external root resorption (IERR) is a pathological process defined by the progressive loss of dental hard tissue, dentin, and cementum, resulting from the combination of the loss of external root protective apparatus and root canal infection. It has been suggested that healing patterns after tooth replantation may be influenced by the genetic and immunological profiles of the patients. The purpose of the present investigation was to evaluate the DNA methylation patterns of 22 immune response-related genes in extracted human teeth presenting with IERR. Methylation assays were performed on samples of root fragments showing IERR and compared with healthy bone tissue collected during the surgical extraction of impacted teeth. The methylation patterns were quantified using EpiTect Methyl II Signature Human Cytokine Production PCR Array. The results revealed significantly higher hypermethylation of the FOXP3 gene promoter in IERR (65.95%) than in the bone group (23.43%) (p < 0.001). The ELANE gene was also highly methylated in the pooled IERR sample, although the difference was not statistically significant (p= 0.054). Our study suggests that the differential methylation patterns of immune response-related genes, such as FOXP3 and ELANE, may be involved in IERR modulation, and this could be related to the presence of root canal infection. However, further studies are needed to corroborate these findings to determine the functional relevance of these alterations and their role in the pathogenesis of IERR.

A multicenter study of biopsied oral and maxillofacial lesions in a Brazilian pediatric population

Abstract The aim of this study was to investigate the prevalence of oral and maxillofacial lesions among children from representative regions of Brazil. A retrospective descriptive study was conducted. Biopsy records comprising the period from 2000 to 2015 were obtained from the archives of three Brazilian oral pathology referral centers. A total of 32,506 biopsy specimens were analyzed, and specimens from 1,706 children aged 0-12 years were selected. Gender, age, anatomical location and histopathological diagnosis were evaluated. Descriptive statistics was carried out. Likelihood ratio tests were used to evaluate the association between the categorical variables. The level of significance was set at 0.05. The post-hoc test was used to identify the subgroups that significantly differed from one another, and the Bonferroni correction was applied. A total of 1,706 oral and maxillofacial lesions were diagnosed in pediatric patients, including 51.9% girls. Oral mucocele was the most prevalent reactive/inflammatory lesion (64%). The most commonly affected sites were the lips (34.5%) and mandible (19.9%). A significant association was observed between age and the group of lesions of the oral cavity (p < 0.001), and between age and anatomical location (p < 0.001). Pediatric oral and maxillofacial lesions were frequent and showed wide diversity, with the prevalence of mucocele. Knowledge of oral lesions is important for pediatric dentists worldwide, since it provides accurate data for the diagnosis and oral health of children.

DNA Aneuploidy in Malignant Salivary Gland Neoplasms is Independent of USP44 Protein Expression

Chromosomal instability, leading to aneuploidy, is one of the hallmarks of human cancers. USP44 (ubiquitin specific peptidase 44) is an important molecule that plays a regulatory role in the mitotic checkpoint and USP44 loss causes chromosome mis-segregation, aneuploidy and tumorigenesis in vivo. In this study, it was investigated the immunoexpression of USP44 in 28 malignant salivary gland neoplasms and associated the results with DNA ploidy status assessed by image cytometry. USP44 protein was widely expressed in most of the tumor samples and no clear association could be established between its expression and DNA ploidy status or tumor size. On this basis, it may be concluded that the aneuploidy of the salivary gland cancers included in this study was not driven by loss of USP44 protein expression.

Resumo Instabilidade cromossômica acarretando aneuploidia é um dos fatores marcantes de neoplasias malignas humanas. USP44 (peptidase específica de ubiquitina 44) é uma importante molécula que exerce um papel regulador no ciclo celular e sua perda pode acarretar em segregação cromossômica deficiente, aneuploidia e desenvolvimento de tumores in vivo. Neste estudo, investigou-se a expressão imuno-histoquímica da proteína USP44 em 28 neoplasias malignas de glândulas salivares, associando-se os resultados com o estado de ploidia do DNA avaliado por citometria de fluxo. A proteína USP44 apresentou ampla expressão na maioria das amostras avaliadas e não foi observada associação entre a expressão protéica e o estado de ploidia do DNA ou extensão do tumor. Baseando-se nos resultados, concluiu-se que a aneuploidia das neoplasias malignas de glândulas de salivares incluídas neste estudo não foi influenciada pela perda de expressão da proteína USP44.

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions

Abstract Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions.

Tratamento odontológico prévio a transplante de células tronco-hematopoiéticas: um relato de caso / Dental treatment prior to hematopoietic stem cell transplant: a case report

O linfoma é uma neoplasia malígna que se desenvolve nos gânglios linfáticos e uma possível abordagem terapêutica para esta doença é o transplante de medula óssea. Sob condições de imunossupressão, todo foco infeccioso pode ser ativado e, em função disto, toda infecção ativa em pacientes pré-transplantes de células hematopoiéticas deve ser erradicada previamente, para prevenir ou reduzir riscos de complicações sistêmicasnestes pacientes. Objetivo: Relatar um caso de atendimento odontológico a um paciente com necessidade premente de transplante de células tronco-hematopoiéticas, acometido de Linfoma não-Hodgkin.

Morphometric evaluation of keratocystic odontogenic tumor before and after marsupialization

The aim of the present study was the morphometric evaluation of the epithelial lining and fibrous capsule in histological specimens of keratocystic odontogenic tumors (KOTs) before and after marsupialization. Histological sections from six KOTs that had undergone marsupialization followed by enucleation were photographed. The thickness and features of the capsule and of the epithelial lining of the tumor were evaluated upon marsupialization and upon subsequent enucleation using Axion Vision software. The histological specimens taken upon marsupialization presented an epithelial lining that is typical of KOTs. After marsupialization, the enucleated specimens had a modified epithelial lining and a fibrous capsule that both presented a greater median thickness (p = 0.0277 and p = 0.0212, respectively), morphological changes, and significant enlargement. These modifications can facilitate full surgical treatment and may well be related to a low KOT recurrence rate.

Análise sociodemográfica e clínica de pacientes submetidos ao transplante alogênico de células-troncos hematopoiéticas / Sociodemographic and clinical analysis of patients subjected to allogeneic hematopoietic stem cell transplantation

Objetivo: Descrever os achados clínicos e sociodemográficos dos pacientes submetidos ao transplante de células-tronco hematopoiéticas (TCTH) e encaminhados à Faculdade de Odontologia da Universidade Federal de Minas Gerais (FO-UFMG). Metodologia: Foram selecionados 39 pacientes pré-TCTH alogênico entre 2006 e 2008. Os dados sociodemográficos e clínicos foram obtidos dos prontuários médicos do dia - 7 ao dia +360 pós-TCTH. Resultados: Foi possível observar que 59% dos pacientes eram homens, 25,6% eram melanoderma e 53,8% eram solteiros. Trinta e três por cento deles possuíam o ensino fundamental, 38,5% eram católicos e 56,4% residiam em casa, sendo que (51,2%) residem em casa própria e, (61,5%) em zona urbana. O saneamento básico estava presente em 64,1%, a coleta seletiva em 69,2% e a água encanada em 64,1%. A medula óssea foi a fonte de células-tronco para o TCTH usada em 61,5% dos casos, a doença de base mais prevalente foi a leucemia (46,4%) e 41% dos pacientes foram a óbito após o TCTH. Além disso, 43,6% dos pacientes apresentaram a doença do enxerto contra o hospedeiro aguda (DECHa) e 62,5% DECHc sistêmica e 58,3% DECHc bucal. Conclusão: Assim, este estudo adiciona ao conhecimento no contexto do TCTH dados referentes ao perfil clínico e sociodemográfico dos pacientes e com isso, sugere que o êxito do transplante compreende na sinergia de todos os aspectos referentes ao transplantado.

Objective: To describe the clinical and sociodemographic findings of the patients subjected to hematopoietic stem cell transplantation (HSCT) and referred to the School of Dentistry of the Federal University of Minas Gerais (FO-UFMG). Method: Thirty-nine pre-allogeneic HSCT patients were selected between 2006 and 2008. The clinical and sociodemographic data were obtained from the medical charts from day -7 to day +360 post-HSCT. Results: It was found that 59% of the patients were male, 25.6% were Black and 53.8% were single. Thirty-three percent of them completed the elementary school, 38.5% were Catholic and 56.4% lived at home; of these, 51.2% owned their houses and 61.5% lived in the urban area. As much as 64.1%, 69.2%, 64.1% of the patients had access to basic sanitation, selective collection of residues and water supply pipelines. The bone marrow was the source of stem cells for the HSCT used in 61.5% of the cases, leukemia was the most prevalent base disease (46.4%), and 41% of the patients died after HSCT. Additionally, 43.6% of the patients presented acute graft-versus-host disease (GVHD), 62.5% presented chronic systemic GVHD, and 58.3% presented oral GVHD. Conclusion: This study adds to the knowledge of HSCT information about the clinical and sociodemographic profile of the patients, suggesting that the success of transplantation encompasses the synergy of all aspects associated with the transplant recipient.

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.

Serotonin transporter gene polymorphisms: a case-control study

Considerable evidence indicates that serotonergic mechanisms, particularly the serotonin transporter, are involved in alcoholism and tobacco use and are influenced by polymorphism of the promoter region of 5HTT (5-HTTLPR). As alcohol and tobacco consumption have been implicated in the pathogenesis of oral cancer, the purpose of this study was to investigate 5-HTTLPR polymorphism in patients with oral squamous cell carcinoma (OSCC) compared with a control group in a sample of Brazilian patients. One hundred and three patients affected by OSCC and 103 volunteers without OSCC were genotyped for 5-HTTLPR. Both groups were matched for age, sex and tobacco use. The chi-squared test was used for statistical analysis (α=0.05). There was no statistically significant difference in 5-HTTLPR genotypes between case and control group (p= 0.408). In conclusion, the present investigation demonstrated that serotonin transporter polymorphisms are not implicated in the OSSC development.

Consideráveis evidências indicam que mecanismos serotoninérgicos, particularmente o transportador de serotonina, estão envolvidos no alcoolismo e no uso de fumo e são influenciados pelo polimorfismo da região promotora do 5HTT (5-HTTLPR). Como o consumo de álcool e fumo está implicado na patogênese do câncer, o objetivo deste estudo foi investigar o polimorfismo 5-HTTLPR em pacientes com carcinoma bucal de células escamosas (CBCE) comparado com um grupo controle em uma amostra de pacientes brasileiros. Cento e três pacientes afetados por CBCE e 103 voluntários sem história de CBCE foram genotipados para 5-HTTLPR. Ambos os grupos foram pareados pela idade, gênero e uso de fumo. O teste do qui-quadrado foi usado para análise estatística. Não houve diferença estatística entre os genótipos dos grupos caso e controle (p= 0,408). Concluindo, a presente investigação demonstrou que os polimorfismos do transportador de serotonina não estão implicados no desenvolvimento do CBCE.

Wilms tumor 1 protein is not expressed in oral lymphangiomas

Lymphangiomas are benign hamartomatous lesions of lymphatic vessels. Wilms Tumor 1 (WT1) is a transcription factor that is activated in some human neoplasias. WT1 protein expression is observed in endothelial cells during angiogenesis and is a useful marker to distinguish between vascular proliferations and vascular malformations. The purpose of the present study is to report a case series of oral lymphangiomas together with an immunohistochemical investigation of WT1. Seventeen cases of oral lymphangioma were retrieved and reviewed. Immunohistochemical analysis of WT1 protein was performed and pyogenic granuloma samples were used as positive controls. The male/female ratio was 1.125 and most of the lesions occurred in young subjects. While pyogenic granuloma showed positive staining for WT1, the endothelial cells lining the thin-walled dilated lymphatic vessels of lymphangiomas were negative for this protein. The findings strengthen the idea that oral lymphangioma is a vascular malformation characterized by lymphatic dilatation without significant endothelial proliferation.

Os linfangiomas são tumores hamartomatosos benignos dos vasos linfáticos. O Wilms Tumor 1 (WT1) é um fator de transcrição que se encontra ativo em algumas neoplasias humanas. A expressão da proteína WT1 é observada em células endoteliais durante a angiogênese e pode ser um marcador útil para distinguir as proliferações vasculares das malformações vasculares. O objetivo deste estudo foi relatar uma série de casos de linfangiomas orais e avaliar a expressão imunoistoquímica da proteína WT1. Dezessete casos de linfangiomas orais foram recuperados e revisados. A análise imunoistoquímica foi realizada e amostras de granuloma piogênico foram utilizadas como controle positivo. A relação homem/mulher foi de 1,125 e a maioria das lesões acometeram pacientes jovens. Enquanto o granuloma piogênico mostrou uma imunopositividade para WT1, as células endoteliais da fina parede dos vasos linfáticos dilatados apresentaram-se negativas para esta proteína. Tais achados reforçam a idéia de que o linfangioma oral é uma malformação vascular caracterizada por dilatação linfática sem uma proliferação endotelial significativa.

Análise comparativa do perfil dos usuários e acesso aos serviços de diagnóstico bucal de duas universidades de Minas Gerais, Brasil / Comparative analysis of the profile of users and access to oral diagnostic services in two universities of Minas Gerais, Brazil

Objetivo: Comparar o perfil dos usuários dos serviços de diagnóstico bucal, levando em consideração a autopercepção sobre a presença de lesão bucal, e o acesso ao serviço de estomatologia de duas universidades de Minas Gerais, Brasil. Materiais e Métodos: Realizou-se estudo exploratório, transversal. Foi aplicado um questionário, por uma acadêmica, em cada universidade, aos pacientes que haviam sido atendidos nas clínicas de estomatologia entre setembro de 2006 e agosto de 2007. Resultados: Responderam ao questionário 200 usuários, 50% em cada um dos serviços, sendo 62% mulheres e 38% homens, com idade média 47,7±16,2 anos. Verificaram-se diferenças estatisticamente significativas entre as duas instituições quanto à renda, ocupação do usuário, encaminhamento ao serviço, meio de transporte utilizado para chegar ao local do atendimento, identificação inicial da lesão e automedicação (p<0,05). A lesão foi percebida em mais de 50% dos casos pelo próprio paciente, sendo que 70% deles foram encaminhados para as clínicas de estomatologia por dentistas. O intervalo de tempo entre o surgimento da lesão e a procura pelo serviço foi demais de seis meses para 43% dos pacientes. A maioria dos usuários não conhecia o serviço de estomatologia das universidades (87%). A resolubilidade foi de 93% para os que tiveram acesso ao serviço. Conclusão: Há semelhança entre o perfil dos usuários e seu acesso aos serviços de estomatologia nas duas universidades. Os usuários não conheciam os referidos serviços, porém não se observou dificuldades em encontrá-los.

Hypomethylation of tumor suppressor genes in odontogenic myxoma

Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tumor suppressor genes P16 (CDKN2A), P21 (CDKN1A), P27 (CDKN1B), P53 (TP53) and RB1 in OM and dental pulp. Methylation was evaluated using methylation-specific polymerase chain reaction (PCR). The transcription was studied in some cases by using reverse transcription quantitative PCR. A higher frequency of unmethylated P27, P53, and RB1 samples was observed in the OM when compared with the dental pulp. OM expressed mRNA of all the genes evaluated. Considering all the samples together, the expression of Rb was higher in the unmethylated samples compared with the partially methylated samples. This investigation revealed hypomethylation of the genes P27, P53, and RB1 in OM. In addition, methylation of tumor suppressor genes was found to be an usual event in normal dental pulp.

O mixoma odontogênico (MO) é um tumor odontogênico benigno de origem mesenquimal caracterizado pela presença de células fusiformes ou estreladas dispostas em abundante matriz extracelular mucóide. A metilação do DNA é caracterizada pela adição de grupos metil em citosinas constituintes de ilhas CpG na região promotora do gene. A metilação pode diminuir a expressão de genes supressores de tumor e contribuir para o desenvolvimento de lesões neoplásicas. O objetivo deste trabalho foi avaliar o padrão de metilação nos genes P16 (CDKN2A), P21 (CDKN1A), P27 (CDKN1B), P53 (TP53), RB1 nos MO e na polpa dental. A metilação foi avaliada pela reação em cadeia da polimerase específica para a metilação. A transcrição dos genes foi estudada em alguns casos pela reação da transcriptase reversa (PCR quantitativa). Uma maior frequência de amostras não metiladas para os genes P27, P53 e RB1 foi observada nos MO quando comparados à polpa dental. Os MO expressaram RNAm de todos os genes avaliados. Considerando todas as amostras juntas, a expressão de Rb foi maior em amostras não metiladas comparadas as amostras parcialmente metiladas. Esta investigação mostrou a hipometilação dos genes P27, P53 e RB1 nos MO. Adicionalmente, a metilação nos genes supressores de tumor é um evento frequente em polpa dental normal.

Clonality analysis of giant cell lesions of the jaws

Despite the importance of clonality to understand the pathogenesis and progression of tumors, it has not been investigated yet in giant cell lesions of the jaws. The aim of this study was to analyze the clonality of peripheral giant cell lesions (PGCL) and central giant cell lesions (CGCL) of the jaws. Six samples of PGCL and 5 samples of CGCL were analyzed in this study using the polymorphic human androgen receptor locus (HUMARA) assay. Three out of the 5 samples of the CGCL and 3 out of 6 samples of PGCL exhibited a monoclonal pattern. Our findings demonstrate that some giant cell lesions of the jaws are clonal, which indicate that these lesions may have a common genetic mechanism of development. Further studies are necessary to better elucidate the molecular mechanisms involved in the pathogenesis of such lesions.

Apesar da importância que a clonalidade das lesões tem para o entendimento da patogênese e progressão dos tumores, ainda não foi feita essa investigação em lesões de células gigantes dos maxilares. O objetivo desse trabalho foi analisar a natureza clonal de lesões periféricas de células gigantes (LPCG) e de lesões centrais de células gigantes (LCCG). Foram analisadas nesse estudo 6 amostras de LPCG e 5 amostras de LCCG, sendo todas elas provenientes de pacientes do sexo feminino. Para essa investigação foi utilizado o método baseado na região polimórfica do exon um do gene humano para oreceptor de andrógeno (HUMARA). Três das 5 amostras de LCCG e 3 das 6 amostras de LPCG exibiram um padrão monoclonal. Nossos resultados demonstram que algumas lesões de células gigantes dos maxilares apresentam uma natureza monoclonal indicando que essas lesões podem ter um mecanismo genético comum de desenvolvimento. Outros estudos são necessários para uma maior compreensão dos mecanismos moleculares envolvidos na patogênese dessas lesões.

Gingival peripheral odontoma in a child: case report of an uncommon lesion

Odontoma in an extraosseous location represents a challenge for diagnosis. This article reports a case of peripheral odontoma and its clinical presentation, histological evaluation and treatment. A 12-year-old boy reported a firm asymptomatic gingival mass in the anterior maxilla with two years of evolution. The procedures for diagnosis included intraoral examination, excisional biopsy and histological analysis. The diagnosis was peripheral odontoma. The follow-up revealed no sign of recurrence. Peripheral odontoma is rare and the differential diagnosis with other gingival masses is rather difficult and must include inflammatory and reactive processes. The definitive diagnosis is based on microscopic features.

Primary diffuse large B-cell lymphoma of the oral cavity

Lymphomas arising within the oral cavity account for only 3.5 percent of all oral malignancies. Diffuse large B-cell lymphoma is a non-Hodgkin lymphoma subtype characterized by diffuse proliferation of large neoplastic B lymphoid cells. This paper reports a case of diffuse large B-cell lymphoma affecting the oral cavity of a Brazilian woman, along with its clinical, microscopical, immunohistochemical, and molecular features.

Linfomas correspondem a 3,5 por cento de todos os casos de lesões malignas de boca. O linfoma difuso de grandes células B é um subtipo de linfoma não-Hodgkin caracterizado pela proliferação difusa de células linfóides B. Este artigo relata um caso de linfoma difuso de grandes células B localizado na cavidade bucal de uma mulher brasileira, incluindo os achados clínicos, microscópicos, imuno-histoquímicos e moleculares.

A clinical case of peripheral ameloblastoma

The peripheral ameloblastoma (PA) is a rare, benign, extraosseous odontogenic soft tissue tumour that is confined to the gingiva or alveolar mucosa. The PA presents the same histological characteristics of intraosseous ameloblastoma, although it is less aggressive than this classical subtype. We report a clinical case of PA of the alveolar mucosa in the right posterior maxilla, highlighting the importance of histological examination to the diagnosis.

Prevalence of oral hemangioma, vascular malformation and varix in a Brazilian population

Hemangioma, vascular malformation and varix are benign vascular lesions, common in the head and neck regions. Studies about the prevalence of these lesions in the oral cavity are scarce. The aim of this study was to estimate the prevalence of and to obtain clinical data on oral hemangioma, vascular malformation and varix in a Brazilian population. Clinical data on those lesions were retrieved from the clinical forms from the files of the Oral Diagnosis Service, School of Dentistry, Federal University of Minas Gerais, Brazil, from 1992 to 2002. Descriptive analysis was performed. A total of 2,419 clinical forms in the 10-year period were evaluated, of which 154 (6.4 percent) cases were categorized as oral hemangioma, oral vascular malformation or oral varix. Oral varix was the most frequent lesion (65.6 percent). Females had more oral hemangioma and oral varix than males. Oral vascular malformation and oral varix were more prevalent in the 7th and 6th decades, respectively. Oral hemangioma and oral varix were more prevalent in the ventral surface of the tongue and oral vascular malformation, in the lips. Oral hemangioma was treated with sclerotherapy (54.5 percent), and vascular malformation was managed with sclerotherapy and surgery (19.4 percent each). The data of this study suggests that benign vascular lesions are unusual alterations on the oral mucosa and jaws.

Hemangioma, malformação vascular e variz são lesões vasculares benignas comuns na região de cabeça e pescoço. Estudos sobre a prevalência dessas lesões em boca são escassos. O objetivo deste estudo foi estimar a prevalência e realizar um levantamento de dados clínicos de hemangioma, malformação vascular e variz de boca. Dados clínicos dessas lesões foram consultados em fichas clínicas do arquivo do Serviço de Diagnóstico Oral da Universidade Federal de Minas Gerais, Brasil, no período de 1992 a 2002. Uma análise descritiva foi realizada. Foram obtidas neste período de 10 anos 2.419 fichas clínicas. Cento e cinqüenta e quatro (6,4 por cento) casos foram categorizados como hemangioma, malformação vascular e variz de boca. Variz de boca foi a lesão mais freqüente (65,6 por cento). Mulheres foram mais acometidas pelos hemangiomas e varizes de boca. Malformação vascular e variz de boca foram mais prevalentes na 7ª e 6ª décadas de vida, respectivamente. A localização prevalente do hemangioma e da variz de boca foi a superfície ventral da língua, e da malformação vascular, os lábios. Hemangioma de boca foi tratado com escleroterapia em 54,5 por cento dos casos e a malformação vascular com escleroterapia e cirurgia em 19,4 por cento cada. Este estudo sugere que lesões vasculares benignas são alterações incomuns na mucosa bucal e nos maxilares.