Interaction of DisBa01 peptide from Bothrops alternatus venom with BRAF melanoma receptors: Modeling and molecular docking.

Metastatic melanoma is highly aggressive and challenging, often leading to a grim prognosis. Its progression is swift, especially when mutations like BRAFV600E continuously activate pathways vital for cell growth and survival. Although several treatments target this mutation, resistance typically emerges over time. In recent decades, research has underscored the potential of snake venoms and peptides as bioactive substances for innovative drugs, including anti-coagulants, anti-microbial, and anti-cancer agents. Leveraging this knowledge, we propose employing a bioinformatics simulation approach to: a) Predict how well a peptide (DisBa01) from Bothrops alternatus snake venom binds to the melanoma receptor BRAFV600E via Molecular Docking. b) Identify the specific peptide binding sites on receptors and analyze their proximity to active receptor sites. c) Evaluate the behavior of resulting complexes through molecular dynamics simulations. d) Assess whether this peptide qualifies as a candidate for anti-melanoma therapy. Our findings reveal that DisBa01 enhances stability in the BRAFV600E melanoma receptor structure by binding to its RGD motif, an interaction absent in the BRAF WT model. Consequently, both docking and molecular dynamics simulations suggest that DisBa01 shows promise as a BRAFV600E inhibitor.

An Approach for Engineering Peptides for Competitive Inhibition of the SARS-COV-2 Spike Protein.

SARS-CoV-2 is the virus responsible for a respiratory disease called COVID-19 that devastated global public health. Since 2020, there has been an intense effort by the scientific community to develop safe and effective prophylactic and therapeutic agents against this disease. In this context, peptides have emerged as an alternative for inhibiting the causative agent. However, designing peptides that bind efficiently is still an open challenge. Here, we show an algorithm for peptide engineering. Our strategy consists of starting with a peptide whose structure is similar to the interaction region of the human ACE2 protein with the SPIKE protein, which is important for SARS-COV-2 infection. Our methodology is based on a genetic algorithm performing systematic steps of random mutation, protein-peptide docking (using the PyRosetta library) and selecting the best-optimized peptides based on the contacts made at the peptide-protein interface. We performed three case studies to evaluate the tool parameters and compared our results with proposals presented in the literature. Additionally, we performed molecular dynamics (MD) simulations (three systems, 200 ns each) to probe whether our suggested peptides could interact with the spike protein. Our results suggest that our methodology could be a good strategy for designing peptides.

E-Volve: understanding the impact of mutations in SARS-CoV-2 variants spike protein on antibodies and ACE2 affinity through patterns of chemical interactions at protein interfaces.

Background: The SARS-CoV-2 pandemic reverberated, posing health and social hygiene obstacles throughout the globe. Mutant lineages of the virus have concerned scientists because of convergent amino acid alterations, mainly on the viral spike protein. Studies have shown that mutants have diminished activity of neutralizing antibodies and enhanced affinity with its human cell receptor, the ACE2 protein. Methods: Hence, for real-time measuring of the impacts caused by variant strains in such complexes, we implemented E-Volve, a tool designed to model a structure with a list of mutations requested by users and return analyses of the variant protein. As a proof of concept, we scrutinized the spike-antibody and spike-ACE2 complexes formed in the variants of concern, B.1.1.7 (Alpha), B.1.351 (Beta), and P.1 (Gamma), by using contact maps depicting the interactions made amid them, along with heat maps to quantify these major interactions. Results: The results found in this study depict the highly frequent interface changes made by the entire set of mutations, mainly conducted by N501Y and E484K. In the spike-Antibody complex, we have noticed alterations concerning electrostatic surface complementarity, breaching essential sites in the P17 and BD-368-2 antibodies. Alongside, the spike-ACE2 complex has presented new hydrophobic bonds. Discussion: Molecular dynamics simulations followed by Poisson-Boltzmann calculations corroborate the higher complementarity to the receptor and lower to the antibodies for the K417T/E484K/N501Y (Gamma) mutant compared to the wild-type strain, as pointed by E-Volve, as well as an intensification of this effect by changes at the protein conformational equilibrium in solution. A local disorder of the loop α1'/ß1', as well its possible effects on the affinity to the BD-368-2 antibody were also incorporated to the final conclusions after this analysis. Moreover, E-Volve can depict the main alterations in important biological structures, as shown in the SARS-CoV-2 complexes, marking a major step in the real-time tracking of the virus mutant lineages. E-Volve is available at http://bioinfo.dcc.ufmg.br/evolve.

Propedia: a database for protein-peptide identification based on a hybrid clustering algorithm.

BACKGROUND: Protein-peptide interactions play a fundamental role in a wide variety of biological processes, such as cell signaling, regulatory networks, immune responses, and enzyme inhibition. Peptides are characterized by low toxicity and small interface areas; therefore, they are good targets for therapeutic strategies, rational drug planning and protein inhibition. Approximately 10% of the ethical pharmaceutical market is protein/peptide-based. Furthermore, it is estimated that 40% of protein interactions are mediated by peptides. Despite the fast increase in the volume of biological data, particularly on sequences and structures, there remains a lack of broad and comprehensive protein-peptide databases and tools that allow the retrieval, characterization and understanding of protein-peptide recognition and consequently support peptide design. RESULTS: We introduce Propedia, a comprehensive and up-to-date database with a web interface that permits clustering, searching and visualizing of protein-peptide complexes according to varied criteria. Propedia comprises over 19,000 high-resolution structures from the Protein Data Bank including structural and sequence information from protein-peptide complexes. The main advantage of Propedia over other peptide databases is that it allows a more comprehensive analysis of similarity and redundancy. It was constructed based on a hybrid clustering algorithm that compares and groups peptides by sequences, interface structures and binding sites. Propedia is available through a graphical, user-friendly and functional interface where users can retrieve, and analyze complexes and download each search data set. We performed case studies and verified that the utility of Propedia scores to rank promissing interacting peptides. In a study involving predicting peptides to inhibit SARS-CoV-2 main protease, we showed that Propedia scores related to similarity between different peptide complexes with SARS-CoV-2 main protease are in agreement with molecular dynamics free energy calculation. CONCLUSIONS: Propedia is a database and tool to support structure-based rational design of peptides for special purposes. Protein-peptide interactions can be useful to predict, classifying and scoring complexes or for designing new molecules as well. Propedia is up-to-date as a ready-to-use webserver with a friendly and resourceful interface and is available at: https://bioinfo.dcc.ufmg.br/propedia.

VTR: A Web Tool for Identifying Analogous Contacts on Protein Structures and Their Complexes.

Evolutionarily related proteins can present similar structures but very dissimilar sequences. Hence, understanding the role of the inter-residues contacts for the protein structure has been the target of many studies. Contacts comprise non-covalent interactions, which are essential to stabilize macromolecular structures such as proteins. Here we show VTR, a new method for the detection of analogous contacts in protein pairs. The VTR web tool performs structural alignment between proteins and detects interactions that occur in similar regions. To evaluate our tool, we proposed three case studies: we 1) compared vertebrate myoglobin and truncated invertebrate hemoglobin; 2) analyzed interactions between the spike protein RBD of SARS-CoV-2 and the cell receptor ACE2; and 3) compared a glucose-tolerant and a non-tolerant ß-glucosidase enzyme used for biofuel production. The case studies demonstrate the potential of VTR for the understanding of functional similarities between distantly sequence-related proteins, as well as the exploration of important drug targets and rational design of enzymes for industrial applications. We envision VTR as a promising tool for understanding differences and similarities between homologous proteins with similar 3D structures but different sequences. VTR is available at http://bioinfo.dcc.ufmg.br/vtr.

Effects on Medical Students of Longitudinal Small-Group Learning about Breaking Bad News.

INTRODUCTION: Delivering bad news is a difficult task for physicians, and medical schools do not always prepare future physicians for this inevitable task. OBJECTIVE: To examine training in breaking bad news, to improve medical students' competence and confidence in dealing with this important aspect of clinical practice. METHODS: An exploratory study using a qualitative approach was done at a Brazilian public university's medical school, which receives 30 medical students per semester. Two focus groups were conducted in 2018, with 15 students per group, before and after the training. The intervention consisted of a 6-month (4 h/wk) course about breaking bad news offered to 30 third-year medical students. The communication course included the perspectives of health care professionals, patients, and their families; the SPIKES protocol and the "ABCDE" mnemonic for delivering bad news; general guidelines; and role-playing/simulation strategies to improve students' skills and reduce their personal limitations. RESULTS: Results of the preintervention focus group demonstrated that only 30% of the students were aware of the importance of breaking bad news and of the existence of specific protocols to guide physicians in these situations. Findings from the postintervention focus group indicated that 90% of students understood the importance and began to apply protocols in their practice. DISCUSSION: Breaking bad news is a challenge for undergraduate medical students. The results of our qualitative study showed that students' perceptions about their capability in delivering bad news increased significantly after regular and focused training. The knowledge, skills, and attitudes acquired strengthened the students' self-reported ability to deal with situations requiring breaking bad news. CONCLUSION: The activities offered helped students develop communication skills. They made connections between their formal training (communication and cognitive skills) and actual clinical practice in a community-based rotation. The knowledge and skills acquired gave them tools needed to deliver bad news in their future clinical practice.

Educação em saúde: agentes comunitários de saúde e estudantes de medicina no controle da dengue / Health education: community health workers and medical students inthe control of dengue epidemics / Educación en salud: agentes comunitarios de salud y estudiantes de medicina en el control del dengue

A Estratégia Saúde da Família, uma das mais bem sucedidas iniciativas para reorganização da AtençãoBásica no Brasil, traz como diferencial o Agente Comunitário de Saúde (ACS), trabalhador da saúde queatua como interlocutor, facilitando o acesso da comunidade a ações promotoras de saúde. No entanto, épouco conhecido o processo de orientação e formação destes trabalhadores para tratar de epidemias, como adengue. Neste contexto, salienta-se a importância da aproximação entre estudantes de Medicina e ACS paraque haja o fortalecimento não só da educação permanente destes trabalhadores, mas também da formaçãoacadêmica dos futuros médicos. O método adotado foi o grupo focal com seis agentes de uma UnidadeBásica de Saúde (UBS) no município de Jataí, Goiás, Brasil. O grupo focal foi conduzido por estudantes docurso de Medicina da Universidade Federal de Goiás, tendo como instrumento roteiro condutor elaboradopor professores e estudantes. Este roteiro foi construído com enfoque em Educação em Saúde, para garantira possibilidade de elaboração de futuras estratégias de ação pelos estudantes, contribuindo para a formaçãotransdisciplinar dos alunos. Em seguida, foi feita a Análise de Conteúdo para análise e interpretação dosdados. Os estudantes observaram que os agentes acreditam que as estratégias comunicacionais adotadassão efetivas e acessíveis. Entretanto, constataram que há falhas comunicacionais a serem sanadas, pois acomunidade continua relutante em por em prática seus conhecimentos, encontrando assim um desafioa ser trabalhado com os agentes comunitários ao longo de sua formação acadêmica, em busca de novasestratégias de ação para o combate da doença. Os alunos já começaram a elaborar suas estratégias de ação,com base em conhecimentos construídos sobre comunicação e saúde coletiva. Acredita-se que este trabalhoé de grande importância para desenvolver habilidades comunicacionais nos estudantes e para fortalecerseu compromisso com a responsividade social.(AU)

The Family Health Strategy represents one of the most successful initiatives for reorganization of primarycare in Brazil. It brings, as differential, the Community Health Workers (CHW), who acts facilitatingcommunity access to effective professional care in the form of health-promoting actions. However, the wayworkers receive training to manage epidemics, as dengue, is almost unknown. In this context, this projectaddresses the importance of bringing together medical students and CHW in order to strengthening not onlycontinuing education of CHW, but also the experienced learning of future physicians. The method adoptedwas the conduction of a focus group with six workers in a primary health care center in a mid-size town ofBrazilian midwest. The focus group was conducted by the tutor and students previously trained on dengueprevention and management. Students identified communicational gaps based on what was told by CHW ascorrect actions related to dengue control, allowing them to start developing action strategies. This approachnot only contributed for continuing education of workers but also became a effective transdisciplinary andinterprofessional education opportunity for the students involved in the process. CHWs believed theircommunication strategies about dengue are effective and affordable, however the students detected somecommunication failures and created opportunities to address these misconceptions. Students have alreadystarted developing their strategies based on knowledge acquired on public health and experienced practicesin the medical school. We believe that this project also offers a great importance for the development ofstudents'communication skills and increase their commitment and social accountability.

La Estrategia Salud de la Familia, una de las más exitosas iniciativas para la reorganización de la AtenciónBásica en Brasil, trae como diferencial el Agente Comunitario de Salud (ACS), trabajador de la salud queactúa como interlocutor, facilitando el acceso de la comunidad a acciones promotoras de salud. Sin embargo,es poco conocido el proceso de orientación y formación de estos trabajadores para tratar de epidemias,como el dengue. En este contexto, se destaca la importancia del acercamiento entre estudiantes de Medicinay ACS para que haya el fortalecimiento no sólo de la educación permanente de estos trabajadores, sinotambién de la formación académica de los futuros médicos. El método adoptado fue el grupo focal conseis agentes de una Unidad Básica de Salud (UBS) en el municipio de Jataí, Goiás, Brasil. El grupo focalfue conducido por estudiantes del curso de Medicina de la Universidad Federal de Goiás, teniendo comoinstrumento un guión conductor elaborado por profesores y estudiantes. Este itinerario fue construidocon enfoque en Educación en Salud, para garantizar la posibilidad de elaboración de futuras estrategias deacción por los estudiantes, contribuyendo a la formación transdisciplinaria de los alumnos. A continuación,se hizo el Análisis de Contenido para análisis e interpretación de los datos. Los estudiantes observaron quelos agentes creen que las estrategias comunicacionales adoptadas son efectivas y accesibles. Sin embargo,constataron que hay fallas comunicacionales a ser sanadas, pues la comunidad continúa reticente en poneren práctica sus conocimientos, encontrando así un desafío a ser trabajado con los agentes comunitarios a lolargo de su formación académica, en busca de nuevas estrategias de acción para desarrollar el combate dela enfermedad. Los alumnos ya comenzaron a elaborar sus estrategias de acción, con base en conocimientosconstruidos sobre comunicación y salud colectiva. Se cree que este trabajo es de gran importancia paradesarrollar habilidades comunicacionales en los estudiantes y para fortalecer su compromiso con laresponsividad social.

Cone-beam computed tomography findings of impacted upper canines.

PURPOSE: To describe the features of impacted upper canines and their relationship with adjacent structures through three-dimensional cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS: Using the CBCT scans of 79 upper impacted canines, we evaluated the following parameters: gender, unilateral/bilateral occurrence, location, presence and degree of root resorption of adjacent teeth (mild, moderate, or severe), root dilaceration, dental follicle width, and presence of other associated local conditions. RESULTS: Most of the impacted canines were observed in females (56 cases), unilaterally (51 cases), and at a palatine location (53 cases). Root resorption in adjacent teeth and root dilaceration were observed in 55 and 47 impacted canines, respectively. In most of the cases, the width of the dental follicle of the canine was normal; it was abnormally wide in 20 cases. A statistically significant association was observed for all variables, except for root dilaceration (p=0.115) and the side of impaction (p=0.260). CONCLUSION: Root resorption of adjacent teeth was present in most cases of canine impaction, mostly affecting adjacent lateral incisors to a mild degree. A wide dental follicle of impacted canines was not associated with a higher incidence of external root resorption of adjacent teeth.

Canal incisivo mandibular em pacientes edêntulos: análise na radiografia panorâmica digital / Mandibular incisive canal in edentulous patients: analysis by means of digitalpanoramic radiography

O objetivo desse trabalho foi avaliar, radiograficamente, a região entre osforames mentonianos quanto à presença e características do canal incisivo mandibular, um importantereparo associado a complicações pós-operatórias das cirurgias de instalação de implantesosseointegráveis. Material e Métodos: cinquenta e dois pacientes edêntulos, atendidos em um períodode doze meses, na Clínica de Prótese Total da Faculdade de Odontologia da Universidade Federalda Bahia, foram submetidos ao exame panorâmico digital. As imagens foram avaliadas por umúnico radiologista e a presença do canal incisivo mandibular, bem como seu comprimento, formatoda trajetória e distâncias em relação à crista óssea alveolar e base mandibular foram registrados.Resultados: a amostra final consistiu de 49 exames. O canal incisivo mandibular foi visualizado emoito radiografias, representando 16,3% da população investigada, com variação de 10,7 a 19,7mmde comprimento. A ocorrência bilateral foi mais frequente (50%), bem como a trajetória horizontal(5 casos). Consideração final: a presença e anatomia intraóssea do canal incisivo mandibularnão devem ser ignoradas no planejamento cirúrgico envolvendo a região anterior da mandíbula.Isso se torna fundamental para evitar intercorrências transoperatórias e também para prevenira ocorrência de distúrbios sensoriais e hemorrágicos no período pós-operatório...

The aim of this study was to radiographically assess the region betweenthe mental foramina for the presence and characteristics of mandibular incisive canal, a major repairassociated with postoperative complications of osseointegrated implant placement surgeries.Material and Methods: Fifty-two edentulous patients treated during twelve months in the DentalClinics of the Federal University of Bahia underwent digital panoramic examination. The imageswere evaluated by a single radiologist and the presence of the mandibular incisive canal, its length,the shape of its trajectory and the distances from the alveolar crest and mandibular base were recorded.Results: The final sample consisted of 49 exams. Mandibular incisive canal was observedin eight radiographs, and accounted for 16.3% of the population investigated, with length varyingfrom 10.7 to 19.7 mm. Bilateral lesions were more frequent (50%), and so was the horizontal path(5 cases). Final consideration: The presence and intraosseous anatomy of mandibular incisive canalshould not be ignored in surgical planning involving the anterior mandible region. This becomes critical to prevent perioperative complications and also to prevent the occurrence of sensory and bleeding disorders in the postoperative period...

A comparative study of internal fixation and intermaxillary fixation on bone repair of mandibular fractures through radiographic subtraction.

Conventional radiographic evaluation of fracture healing is not a reliable method, because it depends on the examinator's experience and the quality of the exam. Therefore, serial images differing in density, contrast and geometrical projection can lead to a misdiagnosis on the postoperative fracture healing. Even in good quality images, little changes in calcified tissues often can't be visualized, because of its little sensibility and because of the limited human sight. The use of more sensitive and objective methods could increase the accuracy of this evaluation. This study intended to compare, by digitalized panoramic radiography, the mandible fracture healing after two different types of treatment: open reduction with internal fixation (group 1) and closed reduction with intermaxillary fixation (group 2). It was taken three postoperative radiographs (within a week, a month and three months after treatment), which were digitalized (600 dpi, 8 bits) and adjusted in brightness and size in Photoshop software. Then these images were evaluated by digital subtraction in ImageTool software. The results revealed greater areas of new bone formation in the internal fixation group, in all the evaluated times. Thus, open reduction with internal fixation resulted in more rapid fracture healing than closed reduction with intermaxillary fixation.

Evaluation of condyle defects using different reconstruction protocols of cone-beam computed tomography.

This study was conducted to investigate how well cone-beam computed tomography (CBCT) can detect simulated cavitary defects in condyles, and to test the influence of the reconstruction protocols. Defects were created with spherical diamond burs (numbers 1013, 1016, 3017) in superior and/or posterior surfaces of twenty condyles. The condyles were scanned, and cross-sectional reconstructions were performed with nine different protocols, based on slice thickness (0.2, 0.6, 1.0 mm) and on the filters (original image, Sharpen Mild, S9) used. Two observers evaluated the defects, determining their presence and location. Statistical analysis was carried out using simple Kappa coefficient and McNemar's test to check inter- and intra-rater reliability. The chi-square test was used to compare the rater accuracy. Analysis of variance (Tukey's test) assessed the effect of the protocols used. Kappa values for inter- and intra-rater reliability demonstrate almost perfect agreement. The proportion of correct answers was significantly higher than that of errors for cavitary defects on both condyle surfaces (p < 0.01). Only in identifying the defects located on the posterior surface was it possible to observe the influence of the 1.0 mm protocol thickness and no filter, which showed a significantly lower value. Based on the results of the current study, the technique used was valid for identifying the existence of cavities in the condyle surface. However, the protocol of a 1.0 mm-thick slice and no filter proved to be the worst method for identifying the defects on the posterior surface.

Evaluation of condyle defects using different reconstruction protocols of cone-beam computed tomography

This study was conducted to investigate how well cone-beam computed tomography (CBCT) can detect simulated cavitary defects in condyles, and to test the influence of the reconstruction protocols. Defects were created with spherical diamond burs (numbers 1013, 1016, 3017) in superior and/or posterior surfaces of twenty condyles. The condyles were scanned, and cross-sectional reconstructions were performed with nine different protocols, based on slice thickness (0.2, 0.6, 1.0 mm) and on the filters (original image, Sharpen Mild, S9) used. Two observers evaluated the defects, determining their presence and location. Statistical analysis was carried out using simple Kappa coefficient and McNemar's test to check inter- and intra-rater reliability. The chi-square test was used to compare the rater accuracy. Analysis of variance (Tukey's test) assessed the effect of the protocols used. Kappa values for inter- and intra-rater reliability demonstrate almost perfect agreement. The proportion of correct answers was significantly higher than that of errors for cavitary defects on both condyle surfaces (p < 0.01). Only in identifying the defects located on the posterior surface was it possible to observe the influence of the 1.0 mm protocol thickness and no filter, which showed a significantly lower value. Based on the results of the current study, the technique used was valid for identifying the existence of cavities in the condyle surface. However, the protocol of a 1.0 mm-thick slice and no filter proved to be the worst method for identifying the defects on the posterior surface.

Multiple stafne bone defects: a rare entity.

Stafne bone defects (SBDs) are generally located in the lingual cortex, close to the mandibular angle. We report the occurrence of multiple SBDs in an asymptomatic patient, a 60-year-old man, referred to a radiology clinic to undergo examination for the purpose of implant planning. The case of multiple SBD presented here, probably the first reported in the literature, reinforces the hypothesis that some cases of SBD may be the result of a focal failure during the ossification of the mandible.

Avaliação da fidelidade de biomodelos de prototipagem rápida: estudo experimental in vivo / Accuracy of rapid biomodel prototyping: an experimental in vivo study

Nos últimos anos, os biomodelos de prototipagem rápida vêm ganhando mais espaço na Odontologia, sobretudo, nas especialidades de Cirurgia e Traumatologia Bucomaxilofacial e Implantodontia. Suas vantagens incluem planejamento mais preciso, diminuição do tempo cirúrgico, consequentemente, também do tempo de anestesia e melhores resultados funcionais e estéticos. Este estudo teve como objetivo comparar medidas lineares obtidas de imagens tridimensionais virtuais (construídas no programa 3D Doctor, a partir de exames de tomografia computadorizada de pacientes portadores de neoplasias odontogênicas nos maxilares) e de seus respectivos biomodelos, obtidos pela técnica de impressão tridimensional. As medidas virtuais foram feitas com a ferramenta régua disponível no próprio programa e as medidas nos biomodelos foram feitas com um paquímetro eletrônico digital, por dois avaliadores e repetidas após uma semana. As médias entre as medidas obtidas foram testadas quanto à distribuição normal pelo teste de Kolmogorov e Smirnov e, posteriormente, foi aplicado o teste t Student para amostras pareadas, com uma probabilidade de erro de 5%. A variabilidade interexaminador foi avaliada pelo coeficiente de Lin. Os resultados demonstraram que não houve diferença estatística (p > 0,05) entre as medidas das imagens virtuais e dos seus respectivos biomodelos, além de uma forte correlação entre os avaliadores tanto para as medidas virtuais (0,9975), quanto para as medidas nos biomodelos (0,9972).

In recent years, rapid biomodel prototyping has been gaining more evidence in Dentistry, particularly on surgical and implantodontic areas. Its advantages include more accuracy on treatment planning, decreased surgical and anesthesia times with better functional and aesthetic results. This study aimed to compare linear measurements (obtained from three-dimensional virtual images, built into the 3-D Doctor software, from computed tomography scans of four patients referred for surgery) and their respective biomodels, obtained by three-dimensional printing technique. The virtual measurements were made with a rule available in the program itself and the measures in the mandible models were made with a digital caliper by two examiners and repeated one week later. Measurement values were tested for normal distribution by Kolmogorov-Smirnov test. The Student´s t-test for paired samples (5% level of significance) was used for comparisons. The inter-examiner variability was assessed by the coefficient of Lin. The results showed no statistical difference (p > 0.05) between measures of virtual images and their respective biomodels, with a strong correlation between examiners for both virtual (0.9975) and biomodels (0.9972) measurements.

Dens invaginatus: a cone beam computed tomography case report / Dens invaginatus: relato de um caso por tomografia computadorizada de feixe cônico

One of the most common dental anomalies is dens invaginatus. As the name indicates, it is an invagination of the coronary or root surface, bounded by enamel, which can be so profound as to simulate the appearance of a tooth inside another. Usually occurs in permanent maxillary lateral incisors, followed by maxillary central incisors, premolars, canines and less frequently molars. In this article we will describe the cone beam computed tomography features of a type III dens invaginatus.

Uma das anomalias dentárias mais comuns é o dens invaginatus. Assim como o nome indica, é uma invaginação da superfície coronária ou radicular, delimitada por esmalte, que pode ser tão profunda a ponto de simular a aparência de um dente dentro do outro. Normalmente ocorre em incisivos laterais superiores permanentes, incisivos centrais superiores, pré-molares, caninos e, menos frequentemente, molares. Neste artigo será descrito os achados por tomografia computadorizada de feixe cônico de um dens invaginatus tipo III.

Atitudes dos cirurgiões-dentistas em relação à proteção radiológica, de acordo com a lei brasileira / Attitudes of dentists in relation to radiological protection, according to brazilian law

Objetivo: Realizar uma pesquisa em consultórios odontológicos na cidade de São José do Rio Preto - SP sobre conhecimento e atitudes dos profissionais sobre proteção radiológica e comparar os dados com as recomendações da Portaria 453 do Ministério da Saúde. Material e Método: Cento e cinqüenta consultórios odontológicos foram visitados e foi aplicado um questionário. Resultados: Observou-se que 26% dos entrevistados não conheciam a lei, 23% não avaliavam radiografias existentes do paciente, 21% não usavam vestimenta plumbífera nos pacientes, 49% não usavam posicionadores de filmes, 58% ainda utilizavam processamento visual; 93% utilizavam filme E ou F, entretanto a média de tempo de exposição foi 0.5 segundo, 14% dos equipamentos possuíam cone localizador e 83% seletor de tempo manual, 17% dos dentistas não se protegiam durante a exposição do paciente e 64% ainda utilizavam disparador com retardo. Conclusão: Há falta de conhecimento sobre proteção radiológica; um programa educacional em Radiologia pode produzir mudanças nas atitudes dos profissionais em relação ao uso da radiação ionizante.

Objective: To perform a research in dental offices in the city of São José do Rio Preto-SP about the practitioners' knowledge and attitudes related to radiological protection and compare the data with the recommendations of Ordinance 453 of the Health Ministry. Material and Methods: One hundred and fifty dental offices were visited and a questionnaire was applied. Results: Was observed that 26% of the interviewed did not know the law, 23% did not evaluate the patient's existing radiographs, 21% did not wear lead clothing in patients, 49% did not use film positioners, 58% still used visual processing, 93% used film E or F, however the average exposure time was 0.5 second, 14% of the equipment had locator cone and 83% had manual time selector, 17% of dentists do not protect themselves during the patient's exposure and 64% still used delayed trigger. Conclusion: There Atitudes dos Cirurgiões-Dentistas em Relação à Proteção Radiológica, de Acordo com a Lei Brasileira Pesquisa Rev Odontol Bras Central 2010;19(51) 305 is a lack of knowledge about radiological protection. An educational program in Radiology can produce changes in attitudes of professionals regarding the use of ionizing radiation.

Diferentes alternativas de clareamento para dentes escurecidos tratados endodonticamente / Different alternatives for bleaching endodontically treated teeth stained

O clareamento de dentes escurecidos e tratados endodonticamente constitui-se em uma possibilidade de tratamento estético que oferece maior preservação da estrutura dental e baixo custo, especialmente quando comparado aos procedimentos invasivos, como a confecção de facetas ou coroas. O peróxido de hidrogênio, o peróxido de carbamida e o perborato de sódio podem ser utilizados na superfície externa e interna dos dentes ou aplicados no interior da câmara pulpar, seguido pelo selamento coronário e troca do material clareador, em períodos de tempo pré-estabelecidos – técnica conhecida como Walking bleach. A aplicação de calor, visando a acelerar a reação química do clareamento dental (técnica termo-catalítica) tem sido questionada pelo fato de se constituir em um possível fator de risco para o desenvolvimento de reabsorção radicular externa, principalmente quando existe histórico de trauma dentário ou defeitos no cemento radicular. Portanto, a indicação precisa do material a ser utilizado deve ter como base o conhecimento da eficiência dos diversos agentes e a segurança do tratamento por eles oferecida. Assim, o objetivo deste estudo é revisar a literatura, considerando as diferentes alternativas de clareamento para dentes tratados endodonticamente e escurecidos, abordando os agentes clareadores mais utilizados, as diferentes técnicas, vantagens e desvantagens, e possíveis efeitos colaterais advindos dessas técnicas.

Sistema rotatório race® / Rotatory system race®

A endodontia, ao longo da história, tem investigado métodos mais rápidos seguros e eficientes na preparação e limpeza dos condutos radiculares. O desenvolvimento de sistemas que utilizam o níquel e o titânio incorporou uma série de mudanças no preparo dos canais radiculares, uma vez que apresenta excelentes propriedades de flexibilidade, resistência à torção e memória quanto a sua forma em relação ao aço. Vários instrumentos rotatórios Ni-Ti têm sido desenvolvidos e sua habilidade de manter a forma do canal tem sido confirmada, com a vantagem adicional de obter um preparo mais eficiente do que o realizado pelas técnicas manuais. Recentemente, foi introduzido um novo grupo de instrumentos rotatórios endodônticos, o Sistema RaCe®(Reamer with Aternating Cutting Edges), com um desenho que torna capaz de preparar canais de forma mais segura, com pouco risco de desvios e perfurações, além de limpar e modelar os condutos efetivamente. O objetivo deste trabalho é apresentar uma revisão de literatura sobre o Sistema RaCe® mostrando suas características, indicações, assim como, os princípios da técnica utilizada pelos mesmos

Profilaxia antimicrobiana pré-operatória: avaliação dos critérios empregados por cirurgiões-dentistas na cidade de Salvador-Ba / Prior surgical antibiotic prophylaxis: evaluation of criterions used by dentists, in Salvador-Ba

A prescrição de antimicrobianos é necessária quando da realização de inúmeros procedimentos odontológicos. No entanto, o uso indiscriminado destes medicamentos pode trazer conseqüencias negativas, com risco para a saúde do paciente e a geração de microorganismos resistentes. Existe uma grande variação de protocolos recomendados, mas pouca base científica para as recomendações. O modo de tratar as infecções é frequentemente empírico, gerando muitas vezes prescrições inadequadas. O objetivo deste estudo foi avaliar os critérios utilizados por uma amostra de cirurgiões-dentistas, da cidade de Salvador-BA, quanto à prescrição de antimicrobianos de forma profilática, antes da intervenção cirúrgica, e determinar quais as drogas mais empregadas e sob qual regime terapêutico. Para isso, foram aplicados questionários a profissionais que atuam nas áreas de clínica geral, cirurgia e traumatologia bucomaxilofacial, endodontia e periodontia. No total foram avaliados 103 questionários. Os resultados revelaram que a amoxicilina é o antimicrobiano de primeira escolha para a maioria dos profissionais e que apenas 33 por cento dos entrevistados empregam corretamente o protocolo de profilaxia antibiótica pré-operatória, segundo a American Heart Association (AHA)