Apical and cervical displacement produced by hand and engine-driven stainless steel and nickel-titanium instruments in simulated curved root canal

The purpose of this study was evaluate the occurrence of displacement on the apical and cervical thirds of artificial curved root canals with 30° of curvature, comparing the use of stainless steel hand and oscillatory files with nickel-titanium (NI-TI) hand, rotary and oscillatory files. Methods: Seventy artificial curved root canals were divided into 7 groups (n=10). All canals were prepared with sizes 15to 40 instruments at the working length according to a crown-down technique. The amount of material removed in the curved portion of the simulated canals at2 mm level outside and 11 mm inside was measured. Data were analyzed statistically by ANOVA and Tukey’s test (p<0.05). Results: There was statistically significant differences (p<0.05) at 2 mm level between NI-TI and steel stainless groups. At 11 mm, statistically significant differences (p<0.05) were observed between the groups that used rotary systems (5 and 6) and the remaining groups. Conclusions: The most centered preparations were those belonging to groups 5 and 6, at both levels. Root canal preparation with NI-TI files yielded better results than the stainless steel files especially when mechanically activated.

Avaliação in vitro das alterações verificadas em canais radiculares artificiais curvos preparados por dois sistemas rotatórios / In vitro evaluation of shape changes in curved artificial root canals prepared with two rotary systems

O objetivo desta pesquisa experimental in vitro foi analisar comparativamente as deformações no canal radicular apóso uso do sistema rotatório de NiTi ProTaper Universal, ProDesign e técnicas híbridas utilizando os dois sistemas. Foram utilizados e instrumentados, setenta e cinco blocos com canais radiculares artificiais, divididos em cinco grupos(n=15). Para o grupo 1, os preparos foram realizados pelo sistema ProTaper Universal, utilizando a lima F3 no preparo apical. Para o grupo 2, utilizou-se o sistema ProDesign com preparo apical usando a lima 30/0,2. Para o grupo 3,os preparos foram realizados pelo sistema ProTaper Universal,utilizando a lima F2 no preparo apical. Para o grupo 4, os sistemas ProDesign e ProTaper foram utilizado sem conjunto com preparo realizado com a lima F2. Para o grupo 5, os sistemas ProDesign e ProTaper foram utilizados em conjunto com preparo apical realizado com as limas F1 e F2. As brocas de Gates-Glidden #5, #4, #3, #2 e#1 realizaram o preparo da porção reta de todos os canais,caracterizando o preparo cervicoapical. Foram analisados a diferença e o quociente da quantidade de resina removida nos seis milímetros de curvatura, aferidos tanto na parte interna quanto na parte externa. Zip e elbow foram quantificados pela forma final, após instrumentação em cada grupo testado. Para análise dos dados utilizou-se os testes paramétricos (ANOVA p<0,05), não paramétrico Kruskal--Wallis (p<0,05) e qui-quadrado (p<0,05). Para diferença e quociente, verificou-se melhores formas para os grupos 2 e3. Através da análise quantitativa e qualitativa, observou-se melhores preparos com o sistema ProDesign e ProTaperUniversal com preparo apical utilizando lima F2.

The aim of this in vitro experimental analysis was to comparethe changes in canal shape after the use of ProTaper UniversalNiTi rotary system, ProDesign system, and a hybridtechnique using both systems. A total of seventy-five simulatedroot canals were prepared and divided into five groups(n = 15). For Group 1, the ProTaper Universal System withapical preparation file F3 was used. For Group 2, ProDesignSystem with apical preparation using file 30/0.2 was used.For Group 3, ProTaper Universal System with apical preparationwith file F2 was applied. For Group 4, ProDesign Systemand ProTaper Universal System with apical preparationwith file F2 were applied. For Group 5, ProDesign Systemand ProTaper Universal System with apical preparation F1and F2 were used. All instrumentation was performed withthe help of Gates-Glidden drills #5, #4, #3, #2 and #1 accordingto crow-down preparation. The difference and thequotient the amount of removed resin were analyzed withinsix millimeters of the canal curvature, measured for both innerand outer walls. The amount of zip and elbow apical formationand mean final shape for each type tested were analyzed.Data were analyzed using parametric tests (ANOVA p<0.05),non-parametric test Kruskal-Wallis (p<0.05) and Chi-squaretest (p<0.05). When difference, quotient and final mean shapewere analyzed, the best preparations were observed in groups2 and 3. Through qualitative and quantitative analysis, thebest preparations were obtained with ProDesign System andProTaper Universal System with apical preparation file F2.

Dual resin cement knoop hardness after different activation modes through dental ceramics.

This study investigated the influence of ceramic compositions on Knoop Hardness Number (KHN) immediately and 24 h after polymerization and the effect of activation modes on the KHN of a resin cement. Ten Panavia F 2.0 resin cement discs were activated either directly using curing light, or chemically without light, or through 1.2-thick ceramic discs. The following ceramics were evaluated: Duceram, Cergogold, IPS Empress, IPS Empress 2, Procera, Cercon, In Ceram Alumina and In Ceram Zirconia. The KHN was obtained immediately and after 24-h testing time. Two-way ANOVA and Tukey's test were performed for statistical analysis (p<0.05). Direct activation showed higher KHN than activation through ceramics and chemical activation for both immediate and 24-h post activation. The KHN for 24-h post activation time was higher than that of the immediate post activation time except for the direct activation mode. The glass and di-silicate based ceramics showed higher KHN than alumina- and zirconia-based ceramics, immediately and after 24-h. The reinforced and opaque ceramics had the lowest KHN. The ceramic composition resulted in light attenuation, lower polymerization and lower KHN, and the 24-h testing time promoted an improvement of KHN except for direct activation mode.

Dual resin cement knoop hardness after different activation modes through dental ceramics

This study investigated the influence of ceramic compositions on Knoop Hardness Number (KHN) immediately and 24 h after polymerization and the effect of activation modes on the KHN of a resin cement. Ten Panavia F 2.0 resin cement discs were activated either directly using curing light, or chemically without light, or through 1.2-thick ceramic discs. The following ceramics were evaluated: Duceram, Cergogold, IPS Empress, IPS Empress 2, Procera, Cercon, In Ceram Alumina and In Ceram Zirconia. The KHN was obtained immediately and after 24-h testing time. Two-way ANOVA and Tukey's test were performed for statistical analysis (p<0.05). Direct activation showed higher KHN than activation through ceramics and chemical activation for both immediate and 24-h post activation. The KHN for 24-h post activation time was higher than that of the immediate post activation time except for the direct activation mode. The glass and di-silicate based ceramics showed higher KHN than alumina- and zirconia-based ceramics, immediately and after 24-h. The reinforced and opaque ceramics had the lowest KHN. The ceramic composition resulted in light attenuation, lower polymerization and lower KHN, and the 24-h testing time promoted an improvement of KHN except for direct activation mode.

Este estudo investigou a influência de composições de cerâmica no número de dureza Knoop (KHN), imediatamente e 24 h após a polimerização; e o efeito de modos de ativação na KHN de um cimento resinoso. Dez discos de cimento resinoso Panavia F 2.0 foram ativados diretamente usando uma fonte de luz, ou quimicamente sem luz, ou através de discos de cerâmica com espessura de 1,2 mm. As cerâmicas avaliadas foram Duceram, Cergogold, IPS Empress, IPS Empress 2, Procera, Cercon, In Ceram Alumina e In Ceram Zirconia. O KHN foi obtido nos tempos imediatamente e após 24 h. Os testes ANOVA two-way e Tukey foram realizados para a análise estatística (p<0,05). A ativação direta apresentou maiores KHN que a ativação através das cerâmicas e ativação química, para ambos os tempos testados imediatamente e após 24 h. O KHN para o tempo de ativação testado após 24 h foi superior que o tempo imediatamente, exceto para o modo de ativação direto. As cerâmicas à base de vidro e di-silicato apresentaram KHN superiores que as cerâmicas à base de alumina e zircônia, imediatamente e após 24 h. As cerâmicas mais reforçadas e opacas resultaram um dos menores KHN. A composição da cerâmica resulta em atenuação de luz, menor polimerização e menor KHN; e o tempo de 24 h testado promove uma melhora no KHN, exceto para o modo de ativação direto.

Influence of the internal conditioning of indirect restorations of resin composite in relation to microleakage using LEDs and QTH units.

The current study evaluated in-vitro microleakage of indirect composite inlays fixed with flowable composite and resinous cement and cured by LEDs and QTH units, thus modifying the internal conditioning of the inlays. Thirty-two non-carious teeth were selected and 64 cavity preparations were performed in both enamel and cementum. These teeth were divided into four groups: I--Elipar FreeLight appliance and Filtek Flowable composite; II--Ultralux appliance and Filtek Flowable composite; III--Elipar FreeLight appliance and RelyX cement and IV--Ultralux appliance and RelyX cement. The inlays were internally sandblasted with aluminum oxide, etched with 37% phosphoric acid, washed and silanized. The dental etching was carried out with 37% phosphoric acid for 15 seconds in dentin and 30 seconds in enamel. After being washed and dried, Single Bond dentinal adhesive was then applied, and the inlays were fixed with their respective luting agents, cured in close contact with their surfaces for 60 seconds, thermocycled and immersed in 0.5% basic fuchsine solution. The teeth were then washed and sectioned through the center of the restoration in order for the microleakage readings to be performed using the Image Tool Software. Then, ANOVA and Tukey's statistical tests were applied. In enamel, there was no significant difference for both groups with regard to microleakage; in cementum, the significant difference was 5% (p > 0.005). In agreement with the results, the inlays can be fixed with RelyX and Filtek Flowable resins.

Abordagem profilática contra tuberculose em pacientes infectados pelo HIV em serviço ambulatorial de hospital filantrópico / Prophylactic app roach against tuberculosis in HIV-infected patients in the outpatient service of philanthropic hospital

Introdução: a tuberculose é uma das principais doenças oportunistas que acometem pacientes com HIV/aids. Para reduzir o risco de adoecimento por tuberculose nestes pacientes, o Ministério da Saúde recomenda a realização anual de teste tuberculínico, visando a instituição oportuna de terapia preventiva (TP). Esta abordagem pode ser considerada um parâmetro de avaliação de qualidade de um serviço. Objetivo: analisar a abordagem profilática contra tuberculose em pacientes infectados pelo HIV em serviço ambulatorial de hospital filantrópico. Métodos: estudo retrospectivo de prontuários dos pacientes com HIV/aids que estavam em acompanhamento no Ambulatório de Doenças Infecciosas e Parasitárias da Santa Casa de Misericórdia de Vitória, em dezembro de 2007. Foram explorados fatores que pudessem condicionar a solicitação de PPD e fez-se análise descritiva dos casos em que se realizou TP, bem como dos casos de tuberculose. Resultados: da população de estudo, de 361 pacientes, foram excluídos os que tiveram tuberculose antes ou até os primeiros 3 meses do início do acompanhamento e selecionou-se uma amostra de 334 pacientes. A média de tempo de acompanhamento foi de 5,77 anos e o número médio de PPD por paciente foi de 1,42, observando-se 23,35% dos pacientes sem nenhuma solicitação de PPD. De 178 resultados do primeiro PPD registrados em prontuário, houve 22 exames positivos. Foi instituída TP em 37 casos e ocorreram 15 casos de tuberculose pós-seguimento, correspondendo a uma incidência de 4,5%. Conclusão: foram observadas falhas na abordagem preventiva contra tuberculose, bem como precariedade de registro em prontuário, afetando diretamente a qualidade do atendimento. É importante aprimorar a abordagem médica dirigida à redução do risco de tuberculose nos pacientes com HIV/aids.

Introduction: tuberculosis is one of the main opportunistic diseases which affect HIV/aids patients. In order to reduce the risk of developing tuberculosis in these patients, the Brazilian Health Ministry recommends an annual tuberculin skin test, aimed at establishing oportune preventive therapy (PT). This approach can be considered a parameter of evaluation of the quality of a health service. Objective: analysing the prophylactic approach against tuberculosis in HIV-infected patients in an outpatient clinic of philanthropic hospital. Methods: retrospective study of HIV/aids patients' medical records which were monitored in the Infectious and Parasitary Diseases Ambulatory of the Santa Casa da Misericordia in the city of Vitoria, in December, 2007. Factors that could condition the solicitation of PPD were explored and descriptive analisys was made of the cases in which PT was done, and of tuberculosis cases as well. Results: within the study population of 361, those that had tuberculosis before or up until the first three months from the beginning of themonitoring were excluded and 334 patients were selected. The average monitoring time was 5.77 years and the average number of PPD per patient was 1.42, considering that 23.35% of the patients had no solicitation for PPD. Out of 178 results of the first PPD recorded, 22 were positive. PT was established in 37 cases and there was an occurrence of 15 cases of tuberculosis post-monitoring, corresponding to an incidence of 4.5%. Conclusion: failures in the preventive approach against tuberculosis were observed, as well as the precariousness of medical record keeping, affecting the quality of care directly. Improving the medical approach in reducing the risk of tuberculosis in HIV/aids patients is important.

Effect of refrigeration on bond strength of self-etching adhesive systems.

The purpose of this study was to investigate the tensile bond strength to dentin of three self-etching adhesive systems at refrigerated and room temperatures. Seventy-eight bovine incisors were embedded in self-cured acrylic resin, abraded on a water-cooled lathe and polished with 400- and 600-grit sandpapers to obtain standard dentin surfaces. The specimens were randomly assigned to 6 groups (n=13). Clearfil SE Bond, AdheSE and One-Up Bond F adhesive systems at refrigerated (4 degrees C) and room temperatures (23 degrees C) were applied to dentin according to the manufacturers' instructions. A truncated composite resin (Herculite XRV) cone was bonded to dentin surface. The specimens were stored in distilled water at 37 degrees C for 24 h and submitted to tensile bond strength testing at a crosshead speed of 0.5 mm/min. Means in MPa were analyzed statistically by Student's t-test at 5% significance level. No statistically significant differences (p>0.05) were found between the adhesive systems applied at refrigerated and room temperatures. In conclusion, no adverse effects on tensile bond strength were observed when self-etching adhesive systems were used after being taken directly from the refrigerated storage.

Effect of refrigeration on bond strength of self-etching adhesive systems

The purpose of this study was to investigate the tensile bond strength to dentin of three self-etching adhesive systems at refrigerated and room temperatures. Seventy-eight bovine incisors were embedded in self-cured acrylic resin, abraded on a water-cooled lathe and polished with 400- and 600-grit sandpapers to obtain standard dentin surfaces. The specimens were randomly assigned to 6 groups (n=13). Clearfil SE Bond, AdheSE and One-Up Bond F adhesive systems at refrigerated (4°C) and room temperatures (23°C) were applied to dentin according to the manufacturers' instructions. A truncated composite resin (Herculite XRV) cone was bonded to dentin surface. The specimens were stored in distilled water at 37°C for 24 h and submitted to tensile bond strength testing at a crosshead speed of 0.5 mm/min. Means in MPa were analyzed statistically by Student's t-test at 5 percent significance level. No statistically significant differences (p>0.05) were found between the adhesive systems applied at refrigerated and room temperatures. In conclusion, no adverse effects on tensile bond strength were observed when self-etching adhesive systems were used after being taken directly from the refrigerated storage.

O objetivo deste trabalho foi avaliar a resistênciade união à dentina de três sistemas adesivos autocondicionantes quando estes se encontravam refrigerados ou à temperatura ambiente. Setenta e oito incisivos bovinos foram embutidos em resina acrílica autopolimerizável, desgastados em um torno mecânico sob refrigeração à água, polidos com papel abrasivo de granulação 400 e 600 para obter uma superfície plana em dentina. Os corpos-de-prova foram divididos aleatoriamente em 6 grupos (n=13). Os sistemas adesivos Clearfill SE Bond, AdheSE and One-Up Bond F foram aplicados sobre a dentina de acordo com as instruções dos fabricantes, estando os mesmos refrigerados (4°C) ou à temperatura ambiente (23°C), seguido da união da resina composta Herculite XRV formando um cone invertido. Os corpos-de-prova foram armazenados em água destilada a 37°C por 24 h e submetidos a ensaios de resistência à tração com velocidade de 0,5 mm/min. As médias (em MPa) foram analisadas estatisticamente pelo teste t de Student com nível de significância de 5 por cento. Não houve diferença estatisticamente significante (p>0.05) entre os valores de resistência de união quando os sistemas adesivos encontravam-se refrigerados ou à temperatura ambiente. Concluiu-se que nenhum efeito adverso foi observado na resistência à tração quando os sistemas adesivos foram utilizados imediatamente após a remoção da armazenagem sob refrigeração.

Contrapulsaçäo em operaçäo cardíaca: análise retrospectiva da incidência de infecçäo / Conterpulsation in cardiac surgery: retrospective analysis of the incidence of infections

Recentes avanços tecnológicos ampliaram o uso do balao intra-aórtico como medida de suporte na insuficiência cardíaca aguda. Apesar disto, têm sido descritas algumas complicaçoes relacionadas à sua inserçao, duraçao do uso e localizaçao. O objetivo deste estudo foi investigar retrospectivamente a ocorrência de infecçoes em pacientes críticos que necessitaram do uso do balao intra-aórtico (BIA) após operaçao cardíaca. Entre janeiro de 1990 e julho de 1992, foram revisados os prontuários de 97 pacientes que necessitaram de BlA no pós-operatório de operaçao cardíaca, sendo que apenas 55 apresentavam informaçoes completas que permitiram sua inclusao na revisao. Foram obtidas informaçoes a respeito de ocorrência de infecçoes, resultados de culturas, tipo e tempo de duraçao das operaçoes ,tempo de circulaçao extracorpórea, duraçao da cateterizaçao intravascular e evoluçao clínica. Foram considerados os seguintes locais de infecçao: pulmao, urina, corrente sanguínea, ferida operatória e local de inserçao do BIA. A média de permanência do BIA foi de 3,9 ñ 2,01 dias e os tempos médios de operaçao e de circulaçao extracorpórea foram 8h e 2,5h, respectivamente. Observamos uma alta icidência de infecçoes nestes pacientes, principalmente pneumonia (63,6 por cento). A taxa de infecçao no local de inserçao do BIA foi de 7 por cento e maior que a taxa geral de infecçao da ferida operatória em nossa Instituiçao (3 por cento). Apesar desta alta incidência de infecçoes nao relacionar-se diretamente com ataxa de mortalidade, sugerimos rigorosa vigilância com relaçao à ocorrência de infecçoes e possíveis medidas profiláticas em relaçao a infecçoes pulmonares.