Effect of technique of disinfection by ultrasonic nebulization on accuracy of vinyl polysiloxane impressions

Introduction: To prevent cross-contamination, impressions should be properly disinfected after removing from the mouth. To be efficacious, a successful disinfection must maintain the physico-chemical properties of the impression materials and should not interfere negatively in the fabrication of stone casts. Aim: To evaluate the effect of different disinfection techniques on the accuracy of dental impressions made of vinyl polysiloxane. Materials and Methods: 40 test samples made of vinyl polysiloxane were obtained using a pattern cylinder. The samples were randomly divided into 5 experimental conditions: I-Control, impressions without any disinfection, II-Immersion in 2% glutaraldehyde for 10 minutes, III-Immersion in 0.2% peracetic acid for 10 minutes, IV-ultrasonic nebulization for 10 minutes in 2% glutaraldehyde and V-ultrasonic nebulization for 10 minutes in 0.2% peracetic acid. The impressions obtained were poured in type IV gypsum and both the height and diameter of the stone casts were measured. For this purpose a profile projector joined to a digital measurement system was used. The data were submitted to statistical analysis using Bioestat 5.3 software. The Shapiro-Wilk test was applied to assess normal data distribution. Data were analysed by one-way ANOVA and Tukey's test for comparisons of the means of the different groups, p-value less than 0.05 was considered as statistically significant. Results: Groups I, II and III did not differ statistically among themselves, both in diameter and height. Group IV presented statistically different results from the others for diameter. Whereas for height, the results were shown to be similar among groups I, II, III and IV. For Group V, the results obtained were statistically different for both height and diameter from those of the other groups. Conclusion: The immersion technique did not interfere in the accuracy of the stone casts however the ultrasonic nebulization with 2% glutaraldehyde solution did not show significant differences for height and presented better values of dimensional accuracy in diameter, when compared to the control group. The ultrasonic nebulization method associated with 2% peracetic acid solution presented the worst dimensional accuracy values for height and better values for the diameter compared to the other groups.138ZC01ZC04COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESSem informaçã

Aesthetic dental restoration using direct technique with silicone guides: clinical case report

A reanatomização dental tem se tornado um procedimento de elevada relevância no dia a dia odontológico, uma vez que inconformidades com a aparência estética do sorriso estão cada vez mais frequentes. Para sua realização, várias técnicas e materiais estão disponíveis, dentre os quais restaurações cerâmicas, como lentes de contato, facetas e coroas, além das restaurações em resinas compostas. Estas se destacam por sua abordagem minimamente invasiva, proporcionando características ópticas e mecânicas favoráveis à estrutura dental, as quais permitem a reprodução das caraterísticas dos tecidos dentais naturais, tais como translucidez e opacidade, além de garantir longevidade às restaurações. Várias técnicas podem ser empregadas para a realização da reanatomização com a resina composta, dentre as quais podemos destacar a técnica direta, com o uso de guias de silicone. Assim, este trabalho tem como objetivo apresentar um relato de caso clínico realizado na Clínica de Odontologia da Universidade Estadual do Oeste do Paraná, por meio do uso das guias de silicone vestibular e palatina para o restabelecimento estético dos dentes anteriores superiores, visando a ressaltar sua confecção laboratorial, aplicação clínica e as vantagens de seu uso.Aesthetic dental restoration has become a highly relevant procedure in dentistry routine, since non-conformities with the aesthetic appearance of the smile are more and more frequent. For such, several techniques and materials are available, including ceramic restorations such as contact lenses, veneers and crowns, in addition to composite resin restorations. Composite resins stand out for their minimally invasive approach, providing favorable optical and mechanical characteristics to the dental structure, which allow to reproduce the characteristics of natural dental tissues, such as translucency and opacity, in addition to ensuring longevity to restorations. Several techniques can be used to perform aesthetic dental restorations with composite resin, among which we can highlight the direct technique through use of silicone guides. Thus, this study presents a clinical case report carried out at the Dentistry Clinic of the Western Paraná State University, wherein vestibular and palatal silicone guides were used for the aesthetic restoration of the upper anterior teeth, to emphasize their laboratory manufacture and clinical application, as well as the advantages of its use

Effect of alcohol and substances acid on surface roughness of composite resins

Orientador: Mario Fernando de GoesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo neste estudo foi avaliar in vitro a rugosidade e a morfologia de superfície de resinas compostas armazenadas durante 180 dias em soluções ácidas ou alcoólica presentes na dieta. Sete resinas compostas indicadas para restaurações de dentes anteriores e posteriores foram selecionadas para este estudo (Charisma/Kulzer, Opallis/FGM, Esthet-X/Dentsply, 4Season/Ivoclar, Z250/3M ESPE, Z350/3M ESPE e P90/3M ESPE). Foram confeccionados cinqüenta e um corpos-deprova de cada material com 4 mm de diâmetro e 2 mm de espessura com auxílio de uma matriz de elastômero. Após a fotoativação por 40 segundos (Elipar Free-Light/3M ESPE), os corpos-de-prova foram armazenados em água destilada por 24h a 370C para posterior realização do polimento superficial com discos Soft Lex/3M ESPE na granulação fina e extrafina. Em seguida, os corpos-de-prova foram secos com papel absorvente e a rugosidade de superfície foi mensurada por meio de rugosímetro. Os corpos-de-prova foram então divididos aleatoriamente em cinco grupos (n=7) de acordo com as soluções testadas: G1- Água destilada (pH 5,30); G2 - Vinho tinto/ Trapiche Syha Ind. Argentina (pH 3,68); 3 - Coca-cola®/ Ind. Coca-cola LTDA (pH 2,73); 4 - Suco de laranja/ Purity Cocamar (pH 3,58) e G5 - Solução tampão lactato (2,74). As soluções testadas foram trocadas diariamente. O teste de rugosidade de superfície foi repetido após 15, 90 e 180 dias de imersão. Os valores médios da rugosidade de superfície foram submetidos à análise LSmeans e teste de Tukey-Kramer, em nível de significância de 5%. Os resultados de rugosidade de superfície revelaram que as resinas compostas que apresentaram aumento de rugosidade estatisticamente significativo para todos os períodos e soluções foram Opallis, Esthet-X, 4Season e Charisma. Um corpo-de-prova de cada resina composta foi selecionado para análise morfológica de superfície após 24h, 15, 90 e 180 dias, com microscopia eletrônica de varredura (JEOL- JSM 5600, Tokyo, Japão), numa ampliação de 3000X para revelar as alterações da micro-estrutura de superfície. A análise morfológica de superfície mostrou que as resinas compostas Z350 e P90 foram as mais resistentes à ação das diferentes soluções para os períodos analisados. Enquanto que para as demais resinas compostas foi observada a extrusão das partículas de carga caracterizada por porosidades ou também seu desprendimento permanecendo expostas na superfície. Com base nos resultados pôde-se observar que a degradação superficial das resinas compostas é dependente de sua composição, tempo de armazenamento e do pH da solução.Abstract: The aim of this study was to evaluate in vitro of superficial roughness and surface morphology of composite resins stored 180 days in acid and alcoholic solutions present in the diet. Seven composite resins indicated for the previous and posterior teeth restorations were selected for this study (Charisma / Kulzer, Opallis / FGM, Esthet-X/Dentsply, 4Season/Ivoclar, Z250/3M ESPE ESPE and Z350/3M P90/3M ESPE). Fifty one specimens were made proof-of-each material with 4 mm in diameter and 2 mm thick with elastomer matrix aid. After curing for 40 seconds, the specimens were stored in distilled water for 24h at 370C for subsequent accomplishment of the superficial polishing with disks Soft Lex/3M ESPE and in the thin and extra thin granulation. Then the specimens were proof-of-dry with paper towels and the superficial roughness was measured using a rugosimeter. Specimens were then randomly divided into five groups according to the tested solutions: G1- Distilled water (pH 5,30) G2 - Red Wine / Argentina Trapiche SYHA Ind. (pH 3,68); G3 - Coca-Cola ® / Coca-Cola Ind. LTDA (pH 2,73); G4 - Orange Juice / Purity Cocamar (pH 3,58) and G5 - lactate buffer (pH 2,74). The superficial roughness test was repeated after 15, 90 and 180 days of immersion. The average values of the superficial roughness were statistically analyzed by LSmeans test and Tukey-Kramer test at a significant level of 5%.The results showed that the composite resins that statistically significant increase in roughness for all periods and solutions were Opallis, Esthet-X, 4Season and Charisma. One specimen more representative of each compound resin was selected for morphological analysis of surface after 24, 15, 90 and 180 days. This analysis was made using scanning electron microscopy (JEOL JSM-5600, Tokyo, Japan) at a magnification of 3000X to expose changes in the superficial micro structure. The surface morphology showed that the composite resins Z350 and P90 were more resistant to the action of different solutions for the periods analyzed. The other composite resins were observed displacement of charged particles or porosities also characterized by its detachment staying loose on the surface. Based on the results it was observed that the surface degradation of compound resins is dependent of its composition, storage time and pH solution.DoutoradoMateriais DentariosDoutor em Materiais Dentário

Influência de diferentes fontes fotoativadoras na resistência adesiva de restauração indireta de resina composta

Avaliou-se a influência de diferentes fontes de luz na fotoativação de um cimento resinoso dual. A superfície oclusal de 20 terceiros molares humanos hígidos foi removida para expor a superfície dentinária. Em seguida, foi aplicado sistema adesivo (Adper Single Bond/3M ESPE ) e cimento resinoso dual (RelyX ARC/ 3 M ESPE), de acordo com as recomendações do fabricante. A resina laboratorial de segunda geração (Gradia GC América Inc), com espessura de 4 mm, foi adaptada sobre o dente e procedeu-se à fotoativação. De acordo com o aparelho de luz empregado, os elementos dentais foram divididos em 4 grupos: G1 controle Optilux 401/ Demetron (QTH); G2 L.E.Demetron 1/Demetron (LEDs ); G3 Ultra- Lume LED5/Ultradent (LEDs) e G4 Optilight CL/ Gnatus (LEDs). Os dentes restaurados foram armazenados em soro fisiológico por 24 h. Após o armazenamento, os dentes foram seccionados no sentido vestíbulo-lingual e mésiodistal, para delimitar uma área de 1 mm. Um terceiro corte na base do dente foi realizado com o objetivo de soltar os espécimes. O teste de micro-tração foi empregado para fornecer os valores da resistência adesiva em MPa. Os dados foram submetidos à análise estatística pelo teste ANOVA com p<0,05. Não houve diferenças estatisticamente significante entre os grupos testados. Concluiu-se que a resistência adesiva da interace adesiva fotoativado com LEDs foi semelhante à resistência adesiva obtida quando a lâmpada halógena foi utilizada e que também não houve diferenças entre os diferentes aparelhos LEDs empregados nesse estudo.The following study aims to evaluate the influence between the different light sources in curing light of resin cement. The occlusal surfaces of twenty recently extractew undamaged third human molars were removed in order to expose dentine surface. Immediately after, the bond system (Adper Single Bond/3M ESPE ) and resin cement (RelyX ARC/ 3 M ESPE) was applied in accordance with manufacturer instructions. Second generation laboratory resin of 4 mm thickness was applied over tooth and light curing proceeded. According to light sources employed the teeth were divided in four groups: G1 Control Optilux 401/ Demetron (QTH); G2 L.E.Demetron/Demetron (LEDs ); G3 Ultra-Lume LED5 (LEDs) e G4 Optilight CL/ Gnatus (LEDs). Restored teeth were stored in physiologic serum for 24 h. After stored, teeth were sectioned into vestibule-tongue and mesial-distal to delimit an area with approximately 1 mm, the third cut was made on the base of the tooth in order to release the samples. The microtensile test was employed to reveal the bond strength values in MPa. The data underwent statistical analysis with p<0,05. No statistical significancent difference was found betweem the groups. In conclusion the resin cement bon strength of dual fotoative with LEDs showed similar adhesive resistance test those revelead when halogen lamp was used, and that there also were not differences among the different apparels LEDs used in that study

Desensitizing treatments for dentin hypersensitivity: a randomized, split-mouth clinical trial

The aim of this randomized, controlled, split-mouth, clinical study was to differentiate and clinically qualify the effectiveness of different desensitizing agents in the treatment of painful symptoms caused by cervical dentin hypersensitivity (CDH). Two hundred-and-fifty-two teeth of 42 patients were distributed into seven groups (n = 36): G1 - placebo; G2, G3, G4 and G6 - fluoride varnishes; G5 - sodium fluoride; G7 - potassium oxalate. Three applications were made one week apart. A three-score system (Alfa = 0, Bravo = 2, and Charlie = 3, respectively for no sensitivity, slight sensitivity and high sensitivity) was used to assess CDH after each application and after 30 days. The data were subjected to statistical analysis using the Kruskall-Wallis and Dun tests. After the second week, statistically significant differences were observed for all materials compared with the baseline. After 30 days, Group G7 had presented a significant gradual reduction along all the evaluated time intervals. It was concluded that all the desensitizing agents were capable of reducing dentin hypersensitivity, with the exception of the placebo and the sodium fluoride groups

Influence of different light curing units on the bond strength of indirect resin composite restorations

The aim of this study was to evaluate the influence of different light sources on the bond strength of indirect resin composite restorations cemented with a dual-cure resin cement. The superficial dentin of human third molars was exposed and acid-etched and an adhesive system was applied (Single Bond 2). Four-mm-thick indirect resin composite restorations (Gradia) were fabricated and cemented using a dual-cure resin cement (Rely X). Four light sources were used to polymerize the cement: QTH - Optilux 401; LED1 - L.E.Demetron 1; LED2 - Optilight CL; and LED3 - Ultralume 5. The teeth were stored for 24 h and then sectioned, yielding stick-shaped specimens for each group with a bonded area of 1.0 mm². The specimens were then tested in a universal testing machine, at a crosshead speed of 1 mm/min. Data were analyzed using ANOVA. Bond strength mean values were: QTH: 22.5 (± 8.4); LED1: 22.7 (± 9.4); LED2: 21.4 (± 10.2); and LED3: 27.3 (± 13.8). No statistically significant difference was observed among the experimental groups. The bond strength values when the cement was polymerized using different LED lights were equivalent to the values when the QTH light was used. It can be concluded that the variety of light sources used in the present study did not influence the bond strength of indirect resin composite restorations cemented with a dual-cure resin cement

Influência de três modos de fotopolimerização sobre a microdureza de três resinas compostas

Resumo A adequada fotopolimerização das resinas compostas é fundamental para obtenção de uma boa dureza capaz de resistir aos esforços mastigatórios. Assim, o objetivo deste estudo foi avaliar a influência das técnicas de fotopolimerização - Convencional (CONV), Soft-start (SS) e Pulso atrasado (PA) na microdureza Knoop de três resinas compostas. Para a confecção dos corpos-de-prova foram utilizadas as resinas compostas Filtek Z350 (3M ESPE), Empress Direct (IvoclarVivadent) e P90 (3M ESPE). Foram obtidos nove grupos experimentais em função da técnica de polimerização e resina composta. Vinte e quatro horas após a fotopolimerização foi realizado o teste de microdureza Knoop nas superfícies de base e topo de cada corpo-de-prova. Assim, os valores obtidos foram submetidos ao teste de Kruskall Wallis, seguido do teste de Dunn, p < 0,05. A eficácia da polimerização na superfície de topo das resinas compostas testadas não foi afetada pelos diferentes modos de polimerização. A resina composta Empress Direct apresentou os mais baixos valores de dureza para todos os modos de polimerização quando comparada às demais resinas compostas avaliadas

In vitro evaluation of the antibacterial behavior of a self-etch adhesive associated with chlorhexidine

Abstract Introduction Adhesive technology has been developed quickly since its introduction about fifty years ago. Its goal is to produce a close contact within enamel and dentin. Failures in this process could result in microleakage, and allow the infiltration of bacteria, fluids and ions. Recent studies have been shown the use of chlorhexidine associated with adhesive systems can be able to inhibit the bacteria action. Objective The aim of this study was to evaluate the addiction of different percentages of chlorhexidine to a self-etch adhesive. Methodology The solution of digluconatechlorhexidine was increased to the primer of the two pass self etch adhesive to create a 0.5%, 1.0% and 2.0% chlorhexidine primer solution and after they were distributed in four groups (G1, G2, G3 and G4). Saliva samples (N=10) were used to test bacteria activity. Result They were spread in a blood medium with filter paper disks containing the different treatments. After the incubation, the inhibitions halos formation were evaluated. Conclusion This study demonstrated that, in vitro, the addition of different percentages of chlorhexidine digluconate to the self-etch adhesive induced inhibited halos at bacteria of saliva samples, independent from their concentration