Efeito dos diferentes tipos de polimento sobre a rugosidade de superfície de uma resina acrílica comercial quimicamente ativada: estudo in vitro / Effect of different types of polishing on the surface roughness of a chemically activated commercial acrylic resin: an in vitro study

Objetivo: avaliar in vitro o polimento sobre resina acrílica quimicamente ativada (RAQA), por meio da rugosidade de superfície (Ra). Materiais e Método: Foram confeccionadas 40 amostras de RAQA, com dimensões de 10 a 10 x 2 mm, e foram divididas em quatro grupos (n=10): ausência do acabamento (AA); Ausência de polimento (AP); Polimento químico (PQ); Polimento com borrachas siliconadas + Escovas (PM). Os espécimes foram avaliados no quanto a rugosidade média (Ra) antes e após o envelhecimento em água destilada em uma estufa por 60 dias. Três medições de Ra (µm), na horizontal foram realizadas e calculada uma média para cada espécime. Os dados foram analisados de forma descritiva e inferencial, ANOVA de medidas repetidas e teste de Tukey com nível de significância de 5%. Resultados: Inicialmente, o grupo AA teve os menores valores de Ra e o grupo AP os maiores valores de rugosidade, com média e desvio padrão respectivamente 0,17 (±0,11) e 0,52 (±0,10). Após o envelhecimento, o grupo AA teve as menores médias e o grupo PQ os maiores valores de Ra, sendo 0,38 (±0,20) e 1,33 (±0,32), respectivamente. Os resultados evidenciaram diferença estatística significante quando as amostras foram submetidas ao acabamento com brocas. Conclusão: A RAQA necessita de polimento após acabamento com brocas, uma vez que a ausência de polimento comprometerá a lisura de superfície do material.(AU)

Objective: to evaluate in vitro polishing on chemically activated acrylic resin (RAQA), using surface roughness (Ra). Materials and Method: 40 RAQA samples were made, measuring 10 to 10 x 2 mm, and divided into four groups (n=10): absence of finishing (AA); Lack of polishing (AP); Chemical polishing (PQ); Polishing with silicone rubbers + Brushes (PM). The specimens were evaluated for their average roughness (Ra) before and after aging in distilled water in an oven for 60 days. Three horizontal Ra (µm) measurements were taken and an average was calculated for each specimen. Data were analyzed descriptively and inferentially, using repeated measures ANOVA and Tukey test with a significance level of 5%. Results: Initially, the AA group had the lowest Ra values and the AP group the highest roughness values, with mean and standard deviation respectively 0.17 (±0.11) and 0.52 (±0.10). After aging, the AA group had the lowest averages and the PQ group the highest Ra values, being 0.38 (±0.20) and 1.33 (±0.32), respectively. The results showed a statistically significant difference when the samples were finished with drills. Conclusion: RAQA requires polishing after finishing with drills, as the lack of polishing will compromise the surface smoothness of the material.(AU)

Effect of frozen storage on preservation of a silicone-based test food material

Aim: This study aimed to evaluate the effect of frozen storage on the physical properties of a silicone-based test food material, highly used to evaluate the masticatory performance in research settings. Methods: A total of 1,666 silicone cubes of Optosil Comfort® with 5.6-mm edges were shaped and stored at -18°C. The cubes were subsequently tested for flexural strength (maximum force, displacement, stress, and strain) before breaking (n = 136), changes in weight and size (n = 170), and masticatory performance (n = 1360) at eight timepoints: immediately after cube preparation (baseline, no freezing), and 1, 2, 3 and 4 weeks, and 2, 4 and 6 months after frozen storage. The cubes were thawed 8 h before each assessment. Results: The maximum force, stress, maximum displacement, and deformation values for the cubes were not affected by freezing (P > 0.05). At all of the time points, the cubes exhibited similar weight (P = 0.366) and size (identical values). The masticatory performance for the cubes also showed no differences from baseline through 6 months (P = 0.061). Conclusion: Freezing Optosil Comfort® silicone cubes did not alter the physical and mechanical properties of the material, being suitable to optimize the assessment of masticatory parameters for research purposes

Eficacia del cementado indirecto / Indirect bonding efficiency

La aparición de aparatología preadjustada ha colaborado en la efectividad de los tratamientos de ortodoncia, pero para que la expresión de esta aparatología se logre, es necesario una correcta colocación de los brackets y la permanencia de estos en boca durante todo el tratamiento. La precisión en la colocación mejora con la técnica de cementado indirecta, ya que permite el acceso a las zonas posteriores, a lugares donde se ve disminuida la visión y además disminuye la condensación de aliento y contaminación salival. Si bien esta técnica requiere tiempo extra de laboratorio, es más rápida en la etapa clínica (AU)

Máscara termoplástica recubierta de silicona para el manejo de la cicatriz hipertrófica facial / Silicone coated thermoplastic mask for management of hypertrophic facial scars

Resumen Las quemaduras secundarias a agresión física con intención de desfigurar, torturar o incluso asesinar, se han convertido en un motivo de consulta común en el siglo XXI, siendo Bangladesh el país con la más alta incidencia en el mundo. Colombia es uno de los países con mayor incidencia a nivel de Latinoamérica. La mayoría de las lesiones ocurre en áreas expuestas como el rostro y se acompaña de graves secuelas físicas, estéticas y funcionales. Se realiza la presentación de caso de una paciente de 35 años con quemaduras de tercer grado en región frontal, periocular, malar bilateral, nasal, labial superior y pabellón auricular derecho, manejada con injertos de piel, quien posteriormente desarrolla cicatriz hipertrófica. Se describe el tratamiento con máscara termoplástica elaborada por los profesionales tratantes, con cubierta interna de silicona, fabricada sobre molde a medida y ajustada con bandas elásticas; integrando en un único dispositivo removible, cómodo y de bajo costo, diferentes alternativas terapéuticas que logran modular efectivamente el proceso de cicatrización y por su simplicidad favorecen la adherencia al tratamiento, la cual es indispensable para obtener resultados satisfactorios. MED.UIS.2020;33(3): 49-58

Abstract Burns secondary to physical aggression with the intention of disfiguring, torturing or even murdering, have become a common reason for consultation in the 21st century, with Bangladesh being the country with the highest incidence in the world. Colombia is one of the countries with the highest incidence in Latin America. Most injuries occur in exposed areas such as the face and are accompanied by serious physical, aesthetic and functional sequelae. We present the case of a 35-year-old patient with third degree burns in the frontal, periocular, bilateral malar, nasal, upper labial and right ear region, managed with skin grafts, who later developed a hypertrophic scar. The treatment with a thermoplastic mask made by the treating professionals is described, with an internal silicone cover, made on a custom mold and adjusted with elastic bands; integrating in a single removable, comfortable and low-cost device, different therapeutic alternatives that manage to effectively modulate the healing process and, due to their simplicity, favor adherence to treatment, which is essential to obtain satisfactory results. MED.UIS.2020;33(3): 49-58

Comparative clinical evaluation of breast augmentation using silicone foam coated implants and textured implants

Abstract Purpose To evaluate whether silicone foam implants have a different evolution pattern compared to conventional texture implants. Methods Fifty-eight female patients underwent surgery. They were divided into two groups (silicone foam - Lifesil® - and microtexturized silicone - Lifesil®). The evolution was analyzed in postoperative consultations, with physical examination, photographic documentation and filling in a satisfaction questionnaire, in the postoperative period of one month, four months, one year and then annually, up to a maximum of 3 years of follow-up. Results There were no statistically significant differences in presence of rippling, stretch marks, breast ptosis, capsular contracture and quality of scars. There was a higher rate of patients who were very satisfied with the outcome 360 days after surgery in the group receiving silicone foam implants (p = 0.036). Conclusion In short time, silicone foam envelope implants proved to be as reliable as textured silicone envelope implants, making them an option for augmentation mammoplasty.

Metodologia de ensino de anatomia do globo ocular / Methodology of teaching anatomy of the ocular globe

Resumo Objetivo: O objetivo do presente estudo foi desenvolver uma metodologia que aproxime o discente do conteúdo abordado nas aulas de anatomia do globo ocular. Métodos: Foi realizada uma incisão circular na lâmina orbital do osso frontal de um cadáver humano de uma instituição em saúde e, para acessar as estruturas orbitárias, foram dissecadas as estruturas da área criando uma via para a injeção de uma solução de borracha de silicone branca entre o cristalino e a retina com posterior enucleação e dissecação final. Resultados: O emprego da técnica permitiu que os discentes do curso construíssem o conhecimento tátil do órgão em questão e transformando o saber teórico em prático, reconhecendo músculos, funcionalidade, vasos sanguíneos e estruturas oculares durante o procedimento de dissecação. Conclusão: A metodologia empregada no presente estudo é uma opção viável para o ensino da anatomia do olho.

Abstract Objective: The objective of the present study was to develop a methodology that approximates the student of the content addressed in the classes of anatomy of the eyeball. Methods: A circular incision was made in the orbital blade of the frontal bone of a human cadaver of a health institution and, to access the orbital structures, the area structures were dissected creating a pathway for the injection of a solution of white silicone rubber between the lens and the retina with subsequent enucleation and final dissection. Results: The use of the technique allowed the students of the course to construct the tactile knowledge of the organ in question and transform the theoretical knowledge into practice, recognizing muscles, functionality, blood vessels and ocular structures during the dissection procedure. Conclusion: The methodology used in the present study is a viable option for teaching the anatomy of the eye.

Novas tecnologias e inovações em cirurgia mamária / New technologies and innovations in breast surgery

Introdução: A cirurgia de mama, especialmente as associadas aos implantes de silicone, teve uma crescente popularização, tornando-se a cirurgia plástica mais realizada no mundo. Junto com esta proliferação, observa-se um aumento da preocupação com a segurança dos implantes mamários de silicone, pelas intercorrências relacionadas. Objetivo: Revisar métodos existentes para minimizar as complicações relacionadas com implante mamário de silicone, bem como as tecnologias existentes e tendências tecnológicas para implantes mamários de silicone. Métodos: Foi realizada revisão de artigos científicos relacionados com novas tecnologias e tendências para redução das complicações relacionadas com implantes mamários de silicone, bem como as patentes e fabricantes de implante de silicone mamário. Resultados: Identificamos inicialmente 78 referências, sendo reduzido para 40 para publicação, todos com linhas de pesquisas que buscam melhores resultados e redução das complicações relacionadas com implantes de silicone, seja esta cirurgia com objetivo estético ou reconstrutivo. Conclusão: A busca por um implante mamário que reduza as possíveis e frequentes complicações, principalmente a formação do biofilme, processos infecciosos e resposta imune, é o foco da maioria das pesquisas encontradas. Com o mesmo objetivo, porém surgindo mais recentemente como alternativas, existem as pesquisas para o uso de matriz dérmica acelular e a lipoenxertia, com boas expectativas.

Introduction: Breast surgery with silicone implants is gaining popularity and has become the most performed plastic surgery worldwide. However, there is increasing concern about the safety of silicone breast implants due to associated complications. Objective: To review existing technologies, technological trends, and existing methods to minimize complications related to silicone breast implants. Methods: We conducted a literature review of articles describing new technologies and trends to reduce complications related to silicone breast implants, along with information on patents and manufacturers of silicone breast implants. Results: We initially identified 78 articles, out of which 40 were shortlisted for publication . All articles had a common aim of obtaining better results and reducing complications related to silicone implants, either in aesthetic or reconstructive surgeries. Conclusion: The search for a breast implant that reduces possible and frequent complications, especially biofilm formation, infectious processes, and abnormal immune response, was the focus of most articles studied. Acellular dermal matrix and fat grafting have been reported in the literature as promising alternatives.

Production of Medical Grade Silicone for Facial Prosthesis with Bactericidal Properties from the Inclusion of Poly (Diallyldimethylammonium Chloride): An in Vitro Study

Objective: To evaluate the inclusion capacity and bactericidal efficiency of diallyl dimethyl ammonium chloride (PDADMAC) diluted in tetrahydrofuran (THF) upon inclusion in the medical grade silicone polymer structure. Material and Methods: It was diluted the PDADMAC in THF at the concentration of 4wt%. It was included in the silicon paste during its vulcanization process. The contact angle measurements were performed to evaluate whether the biocide inclusion into the silicon paste was successful. All samples were sterilized with gamma radiation at 25KGy-dosage prior to the microbiological tests. Microbiological testing strictly followed the Antibacterial products - Test for antibacterial activity and efficacy JIS Z 2801: 201010 and the used of specific bacteria, as Staphylococcus aureus ATCC 6538P and Escherichia coli ATCC 8739. Results: The results showed that PDADMAC, when dissolved in THF at 4wt%, displayed good incorporation in medical silicone and a broad-spectrum antibacterial response. The results of the tests using Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538P showed that the silicone with no biocide addition did not present antibacterial activity. In contrast, the experimental group plus 2 mL of PDADMAC would have an ideal antibacterial response. Conclusion: Medical grade silicone can be used as a material with antibacterial properties, since it has been able to keep PDADMAC compound attached to its structure, thus acquiring antimicrobial property.

Avaliação da estabilidade dimensional da silicona de condensação em diferentes tempos de vazamento em moldagens para prótese fixa / Evaluation of the dimensional stability of the condensation silico-ne in different leakage times in moldings for fixed prosthesis

Introdução: O envelhecimento da população aumenta a necessidade de reabilitação protética e o custo do atendimento odontológico. Para reabilitar com qualidade e baixo custo é necessário conhecer os materiais odontológicos desse processo, como os materiais de moldagem. O mais utilizado no Brasil é a silicona de condensação, que possui limitações. Porém, o fabricante modificou a fórmula com o intuito de melhorar a estabilidade dimensional. Objetivo: avaliar a estabilidade dimensional da silicona de condensação Speedex com a nova tecnologia DCP, em diferentes tempos de vazamento nas moldagens para prótese fixa. Material e métodos: Foi confeccionado um modelo padrão metálico com dois cilindros de mesmos diâmetros e mesma altura para simular uma prótese fixa. Foi elaborada uma moldeira metálica padronizada com retenções e guias de inserção. A partir dessa, outras quatro, em acrílico incolor, foram reproduzidas pelo alginato reversível. No total, foram realizadas 20 impressões, sendo 5 impressões por grupo. Os grupos foram vazados com o gesso tipo IV em diferentes tempos: grupo 1 (n=5): imediato; grupo 2 (n=5): 30 min; grupo 3 (n=5): 36h; grupo 4 (n=5): 72h. O modelo padrão e todos os modelos de gesso do grupo 1, 2, 3 e 4 foram medidos por dois pesquisadores de forma cega com auxílio de um paquímetro digital. Foram analisadas as distâncias externas e internas entre os pontos de referência dos cilindros. Os grupos foram comparados pelo teste t de Student, o nível de significância considerado foi p<0,05. Resultados: não se observou diferença estatística entre as medidas do pesquisador 1 e 2 (p>0,05). Não houveram diferenças entre os grupos 1 e 2 e 1 e 3; porém houve diferença significativa entre o 1 e 4. Conclusão: A silicona de condensação Speedex, não altera a estabilidade dimensional com o vazamento em até 36 horas.

Introduction: The aging of the population increases the need for prosthetic rehabilitation and the cost of dental care. To rehabilitate with quality and low cost is necessary to know the dental materials of this process, such as impression materials. The most used in Brazil is condensation silicon, which has limitations. However, the manufacturer modified the formula to improve dimensional stability. Objective: To evaluate the dimensional stability of Speedex condensation silicon with the new DCP technology at different casting times in fixed prosthesis moldings. Material and methods: A standard metal model with two cylinders of the same diameters and the same height was made to simulate a fixed prosthesis. A standard metal tray with drawers and insertion guides was developed. This metal tray was duplicated using reversible alginate. From this, four colorless acrylic trays were reproduced. In total, 20 impressions were made, with 5 impressions per group. The groups were cast with type IV gypsum at different times: group 1 (n=5): immediate; Group 2 (n=5): 30 min; group 3 (n=5): 36h; group 4 (n=5): 72h. The standard model and all gypsum models of groups 1, 2, 3 and 4 were measured by two researchers blindly using a digital caliper. The external and internal distances between the reference points of the cylinders were analyzed. The groups were compared by Student's t test, the significance level considered was p<0.05. Results: no statistically significant difference was found between researcher 1 and 2 by (p<0.05). There were no differences between groups 1 and 2 and 1 and 3; however, there was a significant difference between 1 and 4. Conclusion: Speedex condensing silicone does not change dimensional stability with leakage within 36 hours. Key-words: Dental Impression Materials, Dental Prosthesis, Silicone Elastomers. Submetido: 14/06/2019Aceito: 16/08/2019 Rebeca Vidal Capelupi1,2,Viviam Salvato de Souza1,2,Marcelo Tarcísio Martins1,Júlio Marcos Gouvêa Chagas1,Rogério Teodoro de Aquino3,Thalyta dos Reis Furlani Zouain-Ferreira1,Fabiana Aparecida Mayrink de Oliveira1,21Faculdade de Ciências Médicas e da Saúde de Juiz de Fora, Curso de Odontologia ­ Juiz de Fora, MG. 2Programa Institucional de Bolsas de Iniciação Científica (PIBIC) ­ FCMS/JF 2018.2 3Usinagem Mecânica Industrial, SENAI, Juiz de Fora, MG. Avaliação da estabilidade dimensional da silicona de condensação em diferentes tempos de vazamento em moldagens para prótese fixaEvaluation of the dimensional stability of the condensation silico-ne in different leakage times in moldings for fixed prosthesis * Fabiana de OliveiraAvenida Barão do Rio Branco, 1871/1105, CentroJuiz de Fora ­ MG CEP: 36013-020 8 fabsmay@hotmail.com

Effect of techniques, trays and materials on accuracy of impressions clinically made / Efeito de técnicas, moldeiras e materiais na exatidão de moldagens odontológicas

Abstract Introduction Making accurate and dimensionally stable impressions to duplicate oral conditions and tooth morphology is an essential step of prosthetic dentistry for fabricating well-fitted indirect restorations and, consequently, ensure the longevity and success of the treatment. Several authors describe pros and cons of different impression techniques, although there is no unanimity among them about the best one. Objective This study evaluated casts' accuracy made by different impression techniques, trays and materials. Material and method 10 patients were selected and 20 impressions from teeth #13 to #16 were performed using single-step (SS) and two-step techniques, made with metal stock and customized acrylic resin partial trays, vinyl polysiloxane and condensation silicone rubbers. Type IV gypsum was used to pour the casts. Three photographs of each patient (baseline), as their respective gypsum casts, were taken, measured in their interested buccal surface area. Comparisons of area values among experimental groups and baseline were performed. Data showed adherence to normal curve, being submitted to 3-way ANOVA/Bonferroni test (α=.05). Result Technique produced significant differences (P=0.02). SS technique was more accurate than BUR one (P=0.003; 95=1.22 to 5.98), but both resulted in similar casts to PVC, MOV and NR techniques, which were similar to each other (P>0.05). Conclusion SS technique showed the closest absolute values to baseline.

Resumo Introdução Realizar moldagens precisas e dimensionalmente estáveis que dupliquem a condição oral é um passo essencial para a confecção de restaurações indiretas de qualidade, garantindo seu sucesso e longevidade. Diversos estudos tem demonstrado os prós e contras de diferentes técnicas de moldagem, mas nenhum consenso da melhor técnica ainda foi descrito. Objetivo Este estudo avaliou a exatidão de modelos de gesso confeccionados por diferentes técnicas de moldagem, moldeiras e materiais. Material e método 10 pacientes foram selecionados e 20 moldes dos dentes #13 até #16 foram realizados utilizando técnicas simultânea (SS) e de dois passos, realizados com moldeiras parciais metálicas e individuais de resina acrílica, silicones de adição e condensação. Gesso tipo IV foi usados para os vazamentos. Três fotografias de cada paciente (baseline), assim como dos seus respectivos modelos de gesso foram realizadas e sua área foi então mensurada, na porção vestibular. Comparações de valores de área entre os grupos experimentais e o baseline foram performadas. Os dados mostraram aderência a curva normal, sendo submetidos ao teste 3-way ANOVA/Bonferroni (α=.05). Resultado As técnicas produziram diferenças significativas (P=0.02).Técnica simultânea foi mais precisa que a BUR (P=0.0003; 95=1,22 a 5.98), mas ambas resultaram em modelos similares àqueles feitos por meio das técnicas de PVC, MOV e sem NR, que foram similares entre si (P>0.05). Conclusão Técnica simultânea demonstrou valores absolutos similares àqueles demonstrados pelo baseline.

A simple and effective method for addition silicone impression disinfection

PURPOSE: Although dental impression disinfection is determinant to reduce the cross-infection risk, some studies have shown that, in real practice, the disinfection procedures vary considerably. Thus, the aim of this study was to evaluate the antimicrobial effectiveness and the impact on the dimensional stability of addition silicone' impressions of water wash and the most clinically used disinfection solutions: 3% hydrogen peroxide, commercial disinfectant MD520 (Durr) and 1% and 5.25% sodium hypochlorite. MATERIALS AND METHODS: For this investigation, dental impressions were taken on 16 volunteer dental students. The antimicrobial effectiveness of each procedure was evaluated by pour plate method. The dimensional stability was evaluated using a standardized stainless-steel model, according to ANSI/ADA nº19 specification. RESULTS: The study results showed that water wash does not alter the dimensional stability of addition silicone impressions but doesn't reduce the microbial load of the material (P>.05). On the other hand, addition silicone disinfection by immersion with 3% hydrogen peroxide, MD520 (Durr), or sodium hypochlorite at 1% and 5.25% does not alter the dimensional stability significantly but reduces > 99.9% of the microbial load of the impressions (P<.001). CONCLUSION: Addition silicone impressions should always be disinfected after water wash in order to reduce effectively the cross-infection risk. All disinfectants tested showed high antimicrobial efficiency without significant changes in three-dimensional shape of impressions. Hydrogen peroxide and sodium hypochlorite are of particular importance because are easily accessible in dental setting. The less explored hydrogen peroxide could be a valuable alternative for silicone impressions disinfection.

Force decay evaluation of latex and non-latex orthodontic intraoral elastics: in vivo study

ABSTRACT Objective: This clinical study was conducted in order to evaluate force decay over time of latex and non-latex orthodontic intraoral elastics. Methods: Patients (n = 15) were evaluated using latex and non-latex elastics in the periods of : 0, 1, 3, 12 and 24 hours. The rubber bands were transferred to the testing machine (EMIC DL-500 MF), and force values were recorded after stretching the elastic to a length of 25mm. Paired t test was applied and analysis of variance (ANOVA) was used to evaluate the variation of force generated. LSD (Fisher's least significant difference) post-hoc test was thus employed. Results: As regards the initial forces (zero time), the values of force for non-latex elastic were slightly higher than for the latex elastic. In the subsequent times, the forces generated by the latex elastic showed higher values. Regarding the material degradation, at the end of 24 hours the highest percentage was observed for non-latex elastic. Conclusions: The latex elastics had a more stable behavior during the studied period, compared with non-latex.

RESUMO Objetivo: o objetivo deste estudo clínico foi avaliar e comparar o comportamento dos elásticos de látex e não látex quanto à perda de força ao longo do tempo. Método: os pacientes (n = 15) foram avaliados usando ambos os tipos de material (látex e não látex) em cada tempo: 0, 1, 3, 12 e 24 horas. Os elásticos foram transferidos para a máquina de ensaios mecânicos (EMIC DL-500 MF) e os valores de força foram registrados após a distensão dos elásticos a uma distância de 25 mm. Foi aplicado o teste t pareado, e a análise de variância (ANOVA) foi realizada para verificar a variação das forças geradas em todos os tempos estudados. Em seguida, o teste post-hoc LSD (Fisher's least significant difference) foi aplicado. Resultados: quanto às forças iniciais (tempo zero), os valores de força dos elásticos não látex foram ligeiramente maiores do que dos elásticos de látex. Nos tempos subsequentes, as forças geradas pelos elásticos de látex apresentaram valores superiores às geradas pelos elásticos não látex. Em relação à degradação do material, ao fim do período de 24 horas, o maior percentual foi observado pelos elásticos não látex. Conclusões: os elásticos de látex apresentaram comportamento mais estável durante o período de estudo, em comparação aos não látex.

Avaliação da alteração dimensional de quatro marcas comerciais de silicone por reação de adição variando o tempo de armazenagem dos moldes / Dimensional alteration assessment of four silicone brands through addition reaction varying molds storage time

O objetivo deste estudo foi mensurar e comparar a precisão dimensional de modelos de gesso confeccionados por meio de moldagem de impressão única (material pesado/fluído de uma única vez) com quatro diferentes marcas comerciais de silicone polimerizados por reação de adição (Express XT®, Futura®, Aquasil® e Virtual®). Inicialmente, foi confeccionado um modelo acrílico mestre, o qual possuía três pilares metálicos paralelos entre si e equidistantes 50 mm um do outro. Para obtenção dos moldes foram utilizadas cinco moldeiras individuais em acrílico, cujas faces externas adaptavam-se perfeitamente na base do modelo padrão, promovendo o "stop" de inserção da moldeira. Após o procedimento de moldagem e confecção dos modelos experimentais, foram medidas as distâncias entre os três cilindros e o diâmetro de cada cilindro. Essas medições foram feitas por três vezes em um mesmo ponto e, destas, criou-se uma média obtendo os resultados finais. Os valores das distâncias foram analisados estatisticamente por meio de uma análise bifatorial, e as médias comparadas pelo teste de Tukey (5%). Os dados demostraram que todas as marcas analisadas apresentaram alteração dimensional e diferiram entre si quando comparadas.

The objective of this study was to measure and compare the dimensional accuracy of plaster models made by only impression molding (heavy material/fluid at one time) of four different brands of polymerized silicone through addition reaction (Express XT®, Futura ®, Aquasil® and Virtual®). Initially, a master acrylic model was manufactured, which had three parallel metal pillars and equidistant 50 mm from each other. To obtain the impressions, we used five individual acrylic trays, whose external faces perfectly adapted to the standard model base, thus promoting the "stop" of molding insertion. Following the molding procedure and the experimental models manufacturing, distances between the three cylinders and the diameter of each cylinder were measured. These measurements were made three times at the same point, and from these average results were obtained. The distance values were statistically analyzed using a two-factor analysis and the means compared by Tukey test (5%). The data demonstrated that all the analyzed brands presented dimensional changes and differed from each other when compared.

MR Findings of Breast Implant Rupture Presenting with Unusual Breast Enlargement

We report the case of a patient who presented with rupture of a silicone breast implant showing acute and chronic inflammation. Magnetic resonance imaging (MRI) showed silicone foci outside the implant shell and inside the pectoralis muscles that represented intra- and extracapsular ruptures of the implant and silicone granuloma. There were distinct fluid-fluid levels of various signal intensities and no signs of implant collapse such as ‘linguine sign.’ Rather, we detected enlargement of both the implant shell and the breast.

Analysis in vitro of strength degradation comparing latex and non-latex elastics

Aim: This study was conducted in order to evaluate and compare the behavior of latex and non-latex elastics, as the loss of strength over time in vitro. Methods: The study evaluated 15 of each elastic material for the pre-selected times: 0, 1, 3, 12 and 24 hours. The rubber bands were transferred to the testing machine (EMIC DL-500 MF). The force values were recorded after stretching the elastic to a length of 25mm. Independent t-test was applied. Analysis of variance (ANOVA) was used to check the variation of the forces generated between those determined times. To identify between which times the difference was present, Tukey post-hoc test was accomplished. Results: As regards the initial forces (zero time), the values of force for non-latex elastic were slightly higher than the latex elastic. In subsequent times, the forces generated by the latex elastic showed higher values. Regarding the material degradation, at the end of 24 hours the highest percentage was observed for non-latex elastic. Conclusion: The latex elastic had a more stable behavior during the studied period compared with non-latex. Thus, it is suggested that the non-latex elastics should be changed more frequently and that larger initial forces must be applied than the látex elastics

Prevention of laryngeal webs through endoscopic keel placement for bilateral vocal cord lesions / 医学前沿

Transoral microresection for treatment of vocal cord lesions involving the anterior commissure may result in anterior glottic webs. In this study, we retrospectively reviewed 54 patients who underwent microsurgery for bilateral lesions involving the anterior commissure and categorized them into two groups. The keel placement and control groups received endoscopic keel placement and mitomycin C, respectively. During the follow-up of at least 1 year, the laryngeal web formation rate significantly decreased in the keel placement group compared with that in the control group (18.6% versus 54.5%, P < 0.05). Furthermore, the voice handicap index-10 scores for patients without web formation decreased in both the keel placement and control groups (P < 0.0001 and P < 0.001, respectively). A pseudomembrane covering the vocal cords was detected in 16.3% (7 of 43) cases after keel removal. A total of 100% (7 of 7) of these cases and 2.8% (1 of 36) of the other cases formed laryngeal webs (P < 0.0001). Endoscopic keel placement could be an effective method for preventing anterior glottic webs after surgery for bilateral vocal cord diseases involving the anterior commissure. The pseudomembrane observed at the time of keel removal may imply a high risk of web formation.

Mechanical irritation by protruding bone: A possible cause of breast implant rupture

Although breast implants have been in clinical use for almost 6 decades and have undergone considerable development during this time, implant rupture is still a dreaded long-term complication. Some obvious external factors, such as trauma, can lead to implant rupture, but many studies have reported a high rate of “spontaneous” implant rupture. Herein, we present two cases with the aim of raising awareness of a new possible cause of “spontaneous” implant rupture: mechanical irritation by bony protrusions.

Síndrome ASIA: prótesis mamarias y enfermedad de Still / ASIA syndrome: breast implant and Still's disease

Las enfermedades del tejido conectivo vinculadas a implantes mamarios de siliconas han sido tema de discusión. En la última década, la siliconosis ha sido incluida dentro del síndrome autoinmune/inflamatorio inducido por adyuvante (ASIA) junto al síndrome de la guerra del Golfo, síndrome de miofascitis macrofágica y fenómenos post vacunales. El ASIA puede manifestarse como lupus, artritis reumatoidea, o más raramente como enfermedad de Still del adulto. Presentamos el caso de una paciente con fiebre prolongada y criterios clínicos compatibles con ASIA y enfermedad de Still. Se resecaron las prótesis y la anatomía patológica descartó linfoma anaplásico ALK (-) vinculado a prótesis. Los médicos debemos estar alertas ante la aparición de estas nuevas entidades asociadas a los implantes mamarios de siliconas.

Connective tissue diseases associated with silicone breast implants have been widely discussed. In the last decade, siliconosis has been included in the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) next to Gulf War syndrome, macrophage myofascitis and postvaccination phenomena. The ASIA syndrome may appear as lupus, rheumatoid arthritis, or more rarely, as adult Still's disease. We discuss the case of a patient with prolonged fever and clinical criteria for ASIA and Still's disease. The prostheses were resected and pathology showed absence of breast implant associated anaplastic lymphoma ALK (-). Physicians should be alert to these new entities linked to silicone breast implants.

Gluteoplastia Técnica Intramuscular (XYZ) / Gluteoplasty using the Intramuscular (XYZ) Method

INTRODUÇÃO: No conceito de beleza corporal, a forma e o tamanho das nádegas são fundamentais, provocando uma crescente busca não só de mulheres, como também de homens, pela cirurgia de gluteoplastia. O objetivo deste trabalho é apresentar a experiência do autor em gluteoplastia com a técnica intramuscular (XYZ). MÉTODO: No período de 2010 a 2015 foram operados 29 pacientes com idades entre 22 e 64 anos (média 43 anos), sendo 26 mulheres (89,66%) e três homens (10,34%). Foram usados implantes redondos ou ovais, com volumes entre 240 e 420 ml (média de 330 ml), dependendo da melhor indicação para cada caso. RESULTADOS: Foram obtidos bons resultados sob o aspecto de aumento de volume e harmonia da região glútea, com alto índice de satisfação dos pacientes. CONCLUSÕES: Na casuística do estudo a técnica intramuscular (XYZ) se mostrou segura, tanto nas cirurgias primárias como nas cirurgias secundárias, para tratar casos de assimetria e/ou implantes visíveis. Com a pré- determinação dos pontos fixos XYZ, o procedimento torna-se seguro e reprodutível.

INTRODUCTION: The shape and size of the buttocks are essential to the notion of bodily beauty. This has resulted in a growing interest in gluteoplasty among both women and men. The aim of the present study was to present the author's experience with gluteoplasty using the intramuscular XYZ method. METHOD: Between 2010 and 2015, 29 patients aged 22 to 64 years (average, 43 years) underwent gluteoplasty; of these 26 were women (89.66%) and 3 were men (10.34%). Round or oval implants were used, with volumes of 240 to 420 ml (average, 330 ml), depending on the individual case. RESULTS: Good results were obtained in terms of volume increase and harmony of the gluteal region, with a high degree of patient satisfaction. CONCLUSIONS: The intramuscular XYZ method was safe, both for primary and secondary surgery, to treat cases of asymmetry and/or visible implants. Predetermining the XYZ reference points makes this procedure safe and reproducible.

Uso de biocidas na superfície de materiais para confecção de próteses bucomaxilofaciais / Use of biocides on the surface of materials for making bucomaxillofacial prostheses

As próteses bucomaxilofaciais têm um importante papel na devolução da estética e de algumas funções para os pacientes. Suas boas condições são primordiais, para que possam exercer suas funções adequadamente e manter o local, onde estão inseridas, livre de infecções e inflamações. Portanto, as não formações de colônias e biofilmes bacterianos em materiais eleitos para confecção dessas próteses trarão benefícios aos pacientes reabilitados. Com esse propósito, o presente artigo verificou a eficiência bactericida dos biocidas policloreto de dialildimetilamônio (PDADMAC) e poliacrilamida catiônica (PAC) quando pincelado em resina acrílica termopolimerizável e silicone de grau médico. Os resultados mostraram que o biocida PDADMAC dissolvido em água obteve boa resposta antibacteriana, quando pincelado sobre ambos os materiais. Já o biocida PAC, entretando, mostrou eficiência antibacteriana apenas quando aplicado resina acrílica termopolimerizável... (AU)

The maxillofacial prosthesis have an important role in reestablishing esthetics and some of the patients functions. The prosthesis' condition is imperative to guarantee their appropriate function and keep the receptor site free of infections or inflammatory processes. Therefore, preventing the infection of the chosen material by bacterial colonies and biofilm can be hazardous to the patient's health. To investigate such problem, the present article evaluated the efficiency of two biocides: pol(diallyldimethylammonium chloride (PDADMAC) and polyacrylamide cationic (PAC). The biocides were applied over heat-cured acrylic resin or silicone. The results shows that the PDADMAC biocide dissolved in water had positive outcome when brushed over both materials. The PAC biocide had antibacterial efficiency only when brushed over the heat-cured acrylic resin... (AU)