Does Making An Adhesive System Radiopaque by Filler Addition Affect Its Bonding Properties?

PURPOSE: To evaluate the radiopacity, bond strength, and micromorphology of experimental filled dental adhesives. MATERIALS AND METHODS: Five experimental filled dental adhesives with different concentrations of radiopaque barium-borosilicate glass (wt%) [0 (R0), 30 (R30), 40 (R40), 50 (R50), and 60 (R60)] and the commercial adhesive Adper Single Bond 2 were used in this study. Specimens were prepared by dispensing the uncured resin into a mold (5.0 mm x 1.0 mm). Digital radiographs (n = 5) of both 1-mm-thick adhesive specimens and tooth were taken with a CCD sensor. The gray levels of enamel, dentin, and adhesive systems were measured by histogram analysis and compared. Adhesives were applied to flat dentin surfaces of third molars (n = 7). Resin composite buildups were constructed and sectioned to obtain resin-dentin bonded sticks to test immediately or after 6 months of water storage. Three specimens for each tooth were qualitatively analyzed using scanning electron microscopy. Data on bond strength and radiopacity were evaluated by two-way and one-way ANOVA, respectively, and Tukey's test (α = 0.05). RESULTS: All experimental filled dental adhesives showed radiopacity similar to enamel (p > 0.05) and most yielded significant reductions of bond strength over time. However, the R30 produced a radiopaque material without jeopardizing the bonding of the material to the dentin substrate. CONCLUSIONS: The addition of 30% barium-borosilicate oxide produced radiopaque adhesives without jeopardizing the bonding to the dental substrate.

Effects of new formulas of bleaching gel and fluoride application on enamel microhardness: an in vitro study.

This in vitro study evaluated the new formulas of bleaching products and the effect of subsequent applications of fluoride on the hardness of enamel during and after tooth bleaching. The crowns of 60 extracted intact human molars were sectioned longitudinally; the buccal part was embedded in acrylic resin, the occlusal part was ground flat, exposing enamel and dentin, and then polished. Baseline Knoop microhardness (KHN) of enamel was determined. The specimens were then randomly divided into six groups of 10 specimens, and each group was assigned to a specific 10% carbamide peroxide (CP) bleaching agent. A: Opalescence, B: Opalescence PF (3% potassium nitrate and 0.11% fluoride), C: Nite White Excel 3 (ACP), D: Opalescence + F (acidulated phosphate fluoride 1.23%), E: Opalescence PF + F, F: Nite White Excel 3 + F. The teeth were bleached for eight hours; after each procedure, the specimens were stored in artificial saliva at 37 degrees C. Immediately after day 21 of bleaching, the specimens in groups D, E and F received fluoride 1.23% for five minutes. KHN tests w ere performedbefore (baseline = control), during (14, 21) and two weeks (35 days) after the bleaching procedure and were statistically compared using ANOVA/Tukey's t-test (alpha < 0.05). The statistical analysis revealed no significant difference among the bleaching materials (p = 0.123). A significant enamel KHN reduction (p < 0.001) was observed for all bleaching materials, with no difference among them. Two weeks after bleaching, all the groups that received fluoride showed a significant increase in microhardness. For the new bleaching formulas, the enamel was restored to a value similar to baseline.

Effect of organic solvents compared to sandblasting on the repair bond strength of nanohybrid and nanofilled composite resins.

BACKGROUND: This study evaluated the effect of different surface treatments on the repair bond strength of nanohybrid (Empress Direct) and nanofilled (Filtek Z350 XT) composite resins. MATERIALS AND METHODS: A total of 120 specimens of each material (7.5 x 4.5 x 3 mm) were prepared and polished with SiC paper. Half of the specimens were kept in water for seven days and the other half for six months; they were then divided into six groups according to the type of surface treatment: negative control (no treatment), Al2O3sandblasted, liquid acetone, acetone gel, liquid alcohol and alcohol gel. Following application of the silane coupling agent and the adhesive system, composite resin cylinders were fabricated on the specimens and light cured (20 seconds). The same composite resins were used for the repair. Additionally, ten intact specimens of each composite resin (without repair) were prepared (positive control). The specimens were then loaded to failure in the microshear mode. Three additional specimens were fabricated in each group, and the surface treatments were analyzed by atomic force microscopy, energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM). RESULTS: The nanofilled composite resin showed higher cohesive strength and repair bond strength than the nanohybrid composite resin. The aging process affected the repair bond strength of the nanofilled composite resin. Al2O3sandblasting was more efficient for the nanofilled composite resin and promoted greater surface roughness in both materials. The solvents demonstrated higher efficacy for the nanohybrid composite resin. CONCLUSION: The strengths resulting from the solvents were material dependent, and Al2O3sandblasting resulted in superior repair bond strength in both materials.

The effect of at-home bleaching and toothbrushing on removal of coffee and cigarette smoke stains and color stability of enamel.

BACKGROUND: The authors conducted a study to evaluate the stain removal ability of tooth bleaching and simulated toothbrushing after coffee and cigarette smoke staining and to determine the enamel susceptibility to restaining. METHODS: The authors used a colorimeter to determine the baseline color of 40 bovine labial enamel surfaces according to the Commission Internationale de l'Eclairage L*a*b* coordinates. They immersed one-half of the specimens in coffee and exposed one-half to cigarette smoke in a smoking machine. They took color measurements again and determined the color change from baseline (ΔE1) for each group. The authors divided each group into two subgroups and subjected the specimens to at-home bleaching (one hour per day for 21 days) or simulated toothbrushing (120 cycles per day for 21 days), followed by another color measurement (ΔE2). The authors repeated both staining procedures (that is, cigarette smoke and coffee) and followed them with a third color measurement (ΔE3). They analyzed the data by using a two-way analysis of variance and the Tukey test (α = 5 percent). RESULTS: Both staining procedures resulted in similar values for ΔE1. The specimens stained with coffee and cigarette smoke exhibited a significant reduction in color change after bleaching (P < .05). However, toothbrushing resulted in a significantly reduced color change only for cigarette smoke-stained specimens (P < .001). The discoloration in coffee-stained specimens increased after restaining, irrespective of the stain removal method (P < .05). CONCLUSIONS: The study results show that at-home bleaching removed both coffee and cigarette smoke staining. The restaining potential was greater for specimens stained with coffee than for those stained with cigarette smoke, regardless of the removal method used. CLINICAL IMPLICATIONS: Six percent hydrogen peroxide at-home bleaching was effective in removing stains caused by coffee or cigarette smoke. However, continued frequent consumption of coffee can increase the staining susceptibility of enamel.

Investigação das propriedades mecânicas de cimentos resinosos duais convencionais e autoadesivos em macro e nanoescala / Investigation of mechanical properties of conventional and self-adhesive resin cements in macro and nanoscale

Objetivo: O objetivo desse estudo foi avaliar e comparar as propriedades mecânicas dos cimentos resinosos duais convencionais e autoadesivos em macro e nanoescala. Métodos: Foram confeccionados 15 espécimes de cada marca de cimentos resinosos, AllCem (FGM), RelyX ARC (3M/ESPE) e RelyX U200 (3M/ESPE), para cada teste realizado (flexão de três pontos, compressão e nanoindentação) de acordo com as instruções dos fabricantes. Os espécimes foram fotoativados com aparelho Optilux Demetron (Kerr) por 40 segundos e armazenados em frascos escuros a 37ºC por 24 horas. Foram obtidos os resultados de resistência flexural, resistência à compressão, dureza e de módulo de Young para os diferentes testes mecânicos. Os dados foram avaliados pelos testes ANOVA, múltiplas comparações de Tukey HSD para análise dos valores de resistência, dureza e módulo de elasticidade entre os diferentes cimentos resinosos e ANOVA dois critérios e múltiplas comparações de Games Howell para análise dos módulos de Young entre os diferentes experimentos. Resultados: Os resultados revelaram que o AllCem obteve os maiores valores de resistência flexural e compressão axial (129±22,01 MPa; 243,71±29,75, respectivamente) e o RelyX U200 os menores valores (82,35±19,83 MPa; 134,57±48,93 MPa, respectivamente). Os valores de dureza não diferiram entre os cimentos estudados. No teste de flexão os valores de módulo de Young não diferiram entre os cimentos resinosos. No teste de compressão axial o AllCem apresentou módulo de Young estatisticamente maiores que dos demais cimentos. Para nanoindentação AllCem e RelyX U200 apresentaram maiores valores de módulo de Young que RelyX ARC. Os valores de módulo de Young diferiram significativamente entre todos os experimentos (p<0.05). Conclusão: Os valores das propriedades dos cimentos resinosos podem ser influenciados pelo tipo de experimento (macro- ou nanoescala) realizado.(AU)

Aim: The aim of this study was to evaluate and compare the mechanical properties of conventional and self-adhesive dual resin cements in macroscale and nanoscale. Methods: Fifteen specimens of each brand of resin cement ­ AllCem (FGM), RelyX ARC (3M/ ESPE), and RelyX U200 (3M/ESPE) ­ were made for each test performed in this study (three point bending, compression, and nanoindentation) according to the manufacturer's instructions. The specimens were photoactivated with Optilux Demetron (Kerr) for 40 seconds and stored in the dark at 37°C for 24 hours. Subsequently, they were submitted to flexural strength and axial compression tests at a speed of 1 mm/min, as well as to the Berkovich nanoindentation test. The results of flexural strength, compressive strength, hardness, and Young's modulus were obtained for the different mechanical tests. Data were evaluated by ANOVA tests; multiple comparisons of Tukey HSD to analyze the values of strength, hardness, and Young's modulus among the different resin cements; and ANOVA two criteria and multiple comparisons of Games Howell to analyze the Young's modulus within the different experiments. Results: The results showed that AllCem obtained the highest values of flexural strength and axial compression (129±22.01, 243.71±29.75 MPa, respectively), while RelyX U200 presented the lowest values (82.35 ± 19.83, 134.57 ± 48.93 MPa, respectively). The hardness values did not differ among the studied cements. In the flexural test, the Young's modulus values did not differ between the resin cements. In the axial compression test, AllCem presented a Young's modulus that was statistically higher than the other cements. In the nanoindentation test, AllCem and RelyX U200 presented higher values for Young's modulus than RelyX ARC. Young's modulus values differed significantly among all experiments (p <0.05). Conclusion: The values of resin cement properties can be influenced by the type of experiment (macroscale and nanoscale) performed.(AU)

Effect of fluoride therapies on the surface roughness of human enamel exposed to bleaching agents.

OBJECTIVES: To evaluate in vitro the effect of fluoride therapies on the surface roughness of human dental enamel exposed to bleaching agents. METHOD AND MATERIALS: Sixty-six specimens obtained from 33 third molars were centrally cut, mounted on acrylic resin supports, polished, and submitted to baseline surface roughness readings (RaB). Next, the specimens were distributed into 11 groups and exposed to one of the bleaching agents-16% carbamide peroxide (CP) or 35% hydrogen peroxide (HP)-and one of the fluoride therapies-0.05% NaF daily (DF); 0.2% NaF weekly (WF); 2% final topical fluoride (FTF); or 2% initial and final topical fluoride (IFTF). The positive control group specimens were exposed to neither bleaching agents nor fluoride therapies. The negative control group specimens were exposed to the bleaching agents but none of the fluoride therapies. After storage in artificial saliva for 7 days, final surface roughness readings (RaF) were taken. Percentage differences between RaB and RaF were analyzed by ANOVA and Tukey HSD tests at a P value of .05. RESULTS: The bleaching agents CP and HP increased the surface roughness compared with the control group; FTF and IFTF reduced the surface roughness of enamel exposed to CP and HP; DF and WF did not reduce the surface roughness of enamel exposed to CP and HP. CONCLUSION: Both bleaching agents tested increased the surface roughness of dental enamel, and both topical fluoride therapies were effective at reducing the increase in enamel surface roughness after bleaching.

Analysis of the association between lactotransferrin (LTF) gene polymorphism and dental caries.

OBJECTIVE: The present study evaluated the association between lactotransferrin (LTF) gene polymorphism (exon 2, A/G, Lys/Arg) and dental caries. MATERIAL AND METHODS: A convenience sample of 110 individuals, 12 years old, was divided into: group 1, 48 individuals without caries experience (DMFT=0), and group 2, 62 subjects with caries experience (DMFT>or=1). DNA was obtained from a mouthwash with 3% glucose solution, followed by a scrapping of the oral mucosa. After DNA purification, polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) was performed to access the study polymorphism. The LTF A/G (Lys/Arg) polymorphism had been previously reported as located in exon 1. RESULTS: Allele 1 of the study polymorphism was associated with low DMFT index and showed a protective effect against caries experience (OR=0.16, IC=0.03-0.76, p=0.01). CONCLUSIONS: Lactotransferrin A/G (exon 2, Lys/Arg) polymorphism was associated with susceptibility to dental caries in 12-year-old students.

The effect of different polishing systems on surface roughness and gloss of various resin composites.

PURPOSE: The purpose of this in vitro study was to evaluate the surface finish and gloss of five direct resin composites polished with six polishing systems. MATERIALS AND METHODS: One hundred and fifty disk-shaped composite specimens (D=10.0 mm, 2-mm-thick, N=30 per material) were made. One side of each specimen was finished with a 16-fluted carbide finishing bur and then polished. Five specimens of each resin composite were randomly assigned to one of the six polishing systems. The surface roughness and gloss were measured with a surface profilometer and a glossmeter. The results were analyzed by two-way analysis of variance and Tukey's t-test (p

Specific concentration evaluation of 16% carbamide peroxide compounded at dispensing pharmacies.

The aim of this work was to evaluate the concentration of carbamide peroxide compounded at different dispensing pharmacies. Immediate concentration analysis was made of bleaching gels dispensed by specialized pharmacies, and of a commercially available gel (control group) (n=20). The carbamide peroxide concentration was determined by titration and the results were analyzed statistically by the Kruskal-Wallis test. The commercial bleaching agent (control group) and one of the gels from the pharmacies presented the best mean concentration values, close to 16%. In conclusion, the concentration of the manipulated and industrialized carbamide peroxide gels presented concentration values differing from 16%.

Análise comparativa de dois produtos de higienização de prótesestotais na remoção do biofilme / Comparative analysis of two cleaning products for biofilm removalof total prosthesis

Introdução: A higiene das próteses totais é importante na prevenção de doenças cardíacas e pulmonares em pacientes idosos. Objetivo: Comparar a eficácia dos métodos de higienização para próteses totais. Materiais e métodos: Foram selecionados 20 pacientes portadores de próteses totais superiores. As próteses foram coradas com fucsina básica e, posteriormente, divididas em dois grupos de acordo com as soluções de higiene: grupo 1 – Corega Tabs® (CT); grupo 2 – hipoclorito de sódio (HS) 2,5%. No grupo 1, as próteses foram submersas em 250 mL de água destilada + 1 pastilha de Corega Tabs, no Grupo 2, em 250 mL de água destilada + 10 mL de hipoclorito de sódio a 2,5% por 5 minutos. Após a imersão, foi escovada a porção interna das próteses por um minuto. As bases internas das próteses foram coradas e fotografadas. Em seguida, realizaram-se imersão e imersão + escovação, e então, foi avaliada a quantidade de placa bacteriana pelo método da contagem de pontos. Os dados foram analisados pelos testes t de Student, ANOVA e múltiplas comparações de Tukey HSD. Resultados: Foram encontradas diferenças significativas entre a quantidade de placa bacteriana inicial e após imersão + escovação para ambos os grupos (CT, 40,12 ± 22,44 e 10,92 ± 11,39; HS, 40,64 ± 24,12 e 13,06 ± 11,08; p < 0,05). Não foram encontradas diferenças entre os grupos 1 e 2 para nenhuma condição teste (inicial, imersão e imersão + escovação) (p > 0,05). Conclusão: CT e HS não apresentaram diferenças para eficiência na remoção de placa bacteriana. O método de imersão + escovação mostrou-se o mais eficaz na remoção de placa bacteriana em próteses totais superiores.

Introduction: The hygiene of the dentures is important in the prevention of heart and lung disease in old patients. Objective: To compare the effectiveness of methods for cleaning dentures in reducing plaque. Materials and methods: We selected 20 patients with maxillary dentures. The prostheses were stained with basic fucsin Replak (Dentsply) and then divided into two groups according to the hygiene solutions: group 1 – Corega Tabs® (CT), group 2 - 2.5% sodium hypochlorite (HS). In group 1, the dentures were submerged in 250 mL of water + Corega Tabs; and group 2 in 250 mL of water + 10 mL of sodium hypochlorite 2.5% for five minutes. After soaking was done, the inner portion of the prosthesis was brushed for one minute. The foundations of internal prostheses were stained and photographed. After the initial period, immersion and immersion + brushing, and then evaluated the amount of plaque by the method of scoring. Data were analyzed by Student´s t-tests, ANOVA and Turkey HSD multiple comparisons. Results: Significant differences were found between the amount of initial plaque and immersion + brushing for both groups (CT, 40.12 ± 22.44 and 10.92 ± 11.39; HS, 40.64 ± 24.12 and 13.06 ± 11.08, p < 0.05). No differences were found between groups 1 and 2 test for any condition (initial, immersion and immersion + brushing) (p > 0.05). Conclusion: CT and HS showed no differences related to the efficiency in removing plaque. The immersion + brushing method proved to be the most efficient at removing plaque from maxillary denture.

Degree of conversion of resin composites light activated by halogen light and led analyzed by ultraviolet spectrometry / Grau de conversão de resinas compostas fotoativadas por luz halógena e LED analisadas por espectrometria ultravioleta

Objectives: The aim of this study was to compare the degree of conversion of different shades ofa composite resin activated with two different light sources. Material and method: Composite resin(Charisma™), A2 and SL were photoactivated with a halogen lamp and a LED based system, at threedifferent light activation times (10, 20 and 40s). The degree of conversion was analyzed by ultravioletspectroscopy with variation in wavelength. The data were submitted to ANOVA and the Games Howelltest (5%). Results: The resin composite shade SL presented a higher degree of conversion in depth thanthe resin composite shade A2. The three light activation times had no infl uence on the degree of conversionin the groups of resin composite SL light activated with halogen light and LED. Conclusion: It wasconcluded that the resin composite SL presented the highest degree of conversion, irrespective of thelight polymerization time and the light source used.

Objetivos: O objetivo deste estudo foi comparar o grau de conversão de uma resina composta com diferentes cores,utilizando duas fontes ativadoras. Material e método: Utilizou-se uma resina composta (Charisma®) nas coresA2 e SL, fotoativada com lâmpada halógena e com sistema LED, em três tempos de fotoativação (10, 20 e 40s).O grau de conversão foi analisado por meio da espectrometria ultravioleta, com variação no comprimento de onda.Os dados obtidos foram submetidos à ferramenta ANOVA e ao teste Games Howel (5%). Resultados: A resinacomposta cor SL apresentou maior grau de conversão que a resina composta cor A2. Os três tempos de fotoativaçãonão infl uenciaram no grau de conversão nos grupos de resina composta SL fotoativadas com luz halógena e LED.Conclusão: A resina composta SL apresentou maior grau de conversão independente do tempo de fotopolimerizaçãoe da fonte de luz utilizada.

Analysis of the association between lactotransferrin (LTF) gene polymorphism and dental caries

OBJECTIVE: The present study evaluated the association between lactotransferrin (LTF) gene polymorphism (exon 2, A/G, Lys/Arg) and dental caries. MATERIAL AND METHODS: A convenience sample of 110 individuals, 12 years old, was divided into: group 1, 48 individuals without caries experience (DMFT=0), and group 2, 62 subjects with caries experience (DMFT>1). DNA was obtained from a mouthwash with 3 percent glucose solution, followed by a scrapping of the oral mucosa. After DNA purification, polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) was performed to access the study polymorphism. The LTF A/G (Lys/Arg) polymorphism had been previously reported as located in exon 1. RESULTS: Allele 1 of the study polymorphism was associated with low DMFT index and showed a protective effect against caries experience (OR=0.16, IC=0.03-0.76, p=0.01). CONCLUSIONS: Lactotransferrin A/G (exon 2, Lys/Arg) polymorphism was associated with susceptibility to dental caries in 12-year-old students.

Microtensile bond strength of adhesive systems of single and multiple steps / Resistência à microtração dos sistemas adesivos de única e múltipla etapas

OBJECTIVE: To evaluate the microtensile bond strength of ten dentin adhesive systems. MATERIAL AND METHOD: Sixty human molars were cut to the dentine level and restored with a hybrid composite and one of the adeshive systems. Each teeth were sectioned to obtain sticks measuring 1.0 ± 0.2 mm2, which were then stressed at a crosshead speed of 1mm/min in auniversal testing machine until failure. The failure modes were verified using optical microscopy. RESULTS: One Up Bond FTM, All Bond 2TM, One Step PlusTM, Adper Prompt L-PopTM, OneStepTM, Single BondTM and Clearfil SE BondTM presented no statistically significant differences (p>0.05); the lowest bond strength values were obtained with Scotchbond MPTM, Prime&Bond NTTM and ExciteTM (p<0.05). CONCLUSION: The self etch primer systems and conventional systems exhibited the highest bond strength to dentin, except for Scotchbond MPTM, Prime&BondNTTM and ExciteTM. Adhesive fractures accounted for 69% of the total fractures.

OBJETIVO: Avaliar a resistência adesiva de dez sistemas adesivos. MATERIAIS E MÉTODOS: Os dentes foram seccionados em forma de palitos com tamanho de 1.0 ± 0,2 mm2 e tracionados com velocidade de 1mm/min. Os tipos de fraturas foram verificados utilizando o microscópio óptico. RESULTADOS: Os sistemas adesivos (One Up Bond FTM, All Bond 2TM, One Step PlusTM, Adper Prompt L-PopTM, One StepTM, Single BondTM e Clearfil SE BondTM apresentaram os maiores valores de resistência adesiva em dentina. Os sistemas ScotchbondMPTM, Prime&Bond NTTM e ExciteTM apresentaram menor resistência. CONCLUSÃO: Os sistemas autocondicionantes e os convencionais apresentaram maior resistência adesiva em dentina. Os sistemas Scotchbond MPTM, Prime&Bond NTTM e ExciteTM apresentaram menor resistência adesiva. As fraturas adesivas representaram 69% do total das fraturas.

Specific concentration evaluation of 16 percent carbamide peroxide compounded at dispensing pharmacies

The aim of this work was to evaluate the concentration of carbamide peroxide compounded at different dispensing pharmacies. Immediate concentration analysis was made of bleaching gels dispensed by specialized pharmacies, and of a commercially available gel (control group) (n = 20). The carbamide peroxide concentration was determined by titration and the results were analyzed statistically by the Kruskal-Wallis test. The commercial bleaching agent (control group) and one of the gels from the pharmacies presented the best mean concentration values, close to 16 percent. In conclusion, the concentration of the manipulated and industrialized carbamide peroxide gels presented concentration values differing from 16 percent.

O objetivo deste trabalho foi avaliar a concentração do peróxido de carbamida manipulado em diferentes farmácias de manipulação. Foram utilizados géis clareadores manipulados em farmácias especializadas e um industrializado (grupo controle) (n = 20) com análise de concentração imediata. A concentração do peróxido de carbamida foi obtida por titulometria e os resultados foram submetidos a análise estatística pelo teste de Kruskal-Wallis. Como resultado, o agente clareador (controle) e um dos produtos manipulados em farmácia apresentaram as melhores médias de concentração, próximas a 16 por cento. Pode-se concluir que a concentração do peróxido de carbamida manipulado e dos industrializados apresentaram valores de concentração diferentes de 16 por cento.

Desafios da retenção intrarradicular com pinos de fibrade vidro: revisão de literatura / Challenges of root retention with glass fiber posts: literature review

Recentemente tem sido recomendada a utilizaçãode pinos de fibras de vidro em dentes tratadosendodonticamente devido às propriedades mecânicasserem semelhantes às da dentina. Váriassão as marcas comerciais de pinos, formatos emateriais de composição, porém a maior complexidadeestá na identificação da necessidade, ounão, de núcleo de preenchimento, assim como naescolha do material de retenção. A obtenção deuma boa adesão intrarradicular é de fundamentalimportância para a fixação dos pinos de fibra devidro e para proporcionar um bom selamento radicular,evitando a possibilidade de microinfiltração.Aspectos importantes a serem consideradossão: a anatomia intrarradicular, a fricção/adaptaçãodo pino no interior do canal radicular e a dificuldadede acesso nas regiões mais profundas doconduto, controle de umidade e fator-C. Esta revisãode literatura teve como objetivo apresentaras propriedades biomecânicas dos pinos de fibrasde vidro e os aspectos importantes da retençãono canal radicular.

Recently the use of fibreglass posts has beenrecommended for endodontically treatedteeth owing to their mechanical propertiesbeing similar to those of dentine. Severalcommercial brands of posts are available witha variety of shapes and composite materials,however the most complex task lies in identifyingwhether or not a core is necessary, andalso in choosing the retaining material. Theattainment of good intraradicular adhesionis of fundamental importance for fibreglasspost fixation and for providing good rootsealing in order to prevent the possibility ofmicro-infiltration. Important aspects to beconsidered are intraradicular anatomy, friction/adaptation of the posts inside the rootcanal and difficulty in accessing its deepestregions, humidity control and C-factors. Theaim of this revision of the literature was topresent the biomechanical properties of fibreglassposts and the important aspects ofretention in the root canal.

Análise da microinfiltração marginal em restaurações indiretas utilizando três tipos diferentes de CIV para cimentação / Microleakage evaluation in indirect restorations of three different kinds of glass ionomer cement

O objetivo do trabalho foi avaliar in vitro a microinfiltração marginal cervical em dentina de restaurações indiretas em Artglass (Heraeus/Kulzer) cimentadas com três tipos de ionômero de vidro. Foram utilizados 75 dentes molares extraídos, hígidos, isentos de cárie, com ausência de trincas e defeitos estruturais. Cavidades tipo Classe II foram preparadas dentro de um padrão pré-estabelecido e divididas aleatoriamente em três grupos: G1 - Meron (Voco); G2 - Vidrion C (SS White); G3- Ketac Cem Easy Mix (3M/Espe). Após o preparo, moldagem e a confecção dos blocos, eles foram cimentados com os respectivos agentes cimentantes, seguindo as recomendações do fabricante. Posteriormente, foi realizada a termociclagem com 500 ciclos em temperatura entre 5 +- 2° C e 55 +- 2° C, durante 30 segundos em cada temperatura. Após esse procedimento, os dentes foram imersos em solução de Nitrato de Prata 50%. Para a obtenção dos resultados, foi utilizado o teste não paramétrico de Kruskal-Wallis. Os autores concluíram que todos os grupos apresentaram infiltração marginal, sendo que o G3 apresentou menor tendência de infiltração marginal, seguido do G1 e G2

Análise in vitro da adaptaçäo cervical em cavidades de classe II, restauradas com resina compactável: efeito de técnicas restauradoras / In vitro analysis of the cervical adaptation in class II, restorated with compactable resin: effect of restorative techniques

O propósito deste estudo foi analisar in vitro, através de MEV, a amplitude de fendas marginais cervicais em restauraçöes de classe II, restauradas com resina composta compactável P60 (3M), variando-se diferentes técnicas restauradoras. Foram realizadas 54 cavidades tipo slot nas superfícies M e D de 27 dentes pré-molares hígidos, com todas as margens cervicais localizadas em esmalte. Os preparos foram executados com o auxílio de máquina de padronizaçäo. As cavidades foram restauradas através de incrementos. O adesivo utilizado para todos os grupos foi o Single Bond (3M). Os dentes foram divididos em três grupos, a saber: Grupo T1 - restaurado com resina P60, seguindo as recomendaçöes do fabricante; Grupo T2 - resina P60 associada à ponta fotocondensadora transparente (TDV); Grupo T3 - utilizaçäo de resina fluida Flow-It (Jeneric/Pentron) + resina P60 + ponta fotocondensadora transparente. Após a restauraçäo, os dentes foram armazenados em saliva artificial por sete dias, submetidos à ciclagem térmica (500 ciclos, 5ºC - 55ºC), e entäo seccionados no sentido mésio-distal. Após análise e obtençäo das fotomicrografias em MEV, referentes à regiäo em estudo, a amplitude da fenda cervical foi mensurada. Os resultados foram submetidos à análise estatística de Kruskall-Wallis, e podemos concluir que: 1 - nenhuma das técnicas restauradoras impediu o desenvolvimento de fendas na parede cervical; 2 - o grupo T2, que utilizou a ponta fotocondensadora transparente, apresentou os melhores resultados, estatisticamente significantes, na reduçäo da fenda marginal cervical, quando comparado aos grupos T1 e T3; 3 - o grupo que se utilizou da associaçäo da resina fluida (grupo T3) apresentou os maiores índices de amplitude de fenda marginal

Tratamento restaurador da fratura coronária em dente anterior pela técnica de colagem de fragmento / Restorative treatment of crown fracture on anterior teeth using direct bonding technique

A desarmonia estética em dentes anteriores pode ser causada por alteraçäo de cor, forma e tamanho do elemento dental, bem como pela presença de traumas provenientes de acidentes. No caso de fratura dental coronária, podem ser utilizadas como tratamento restaurador tanto a colagem do fragmento dental (autógeno e heterógeno) quanto restauraçöes diretas e indiretas. A colagem de fragmento autógeno é um procedimento viável para o restabelecimento funcional, morfológico e principalmente estético, tornando-se assim um tratamento restaurador de sucesso. Os autores descrevem um caso clínico desse tipo de colagem por meio de um guia espacial com a finalidade de auxiliar a adaptaçäo do fragmento ao remanescente dental. Concluem que esta técnica de colagem de fragmento é indicada por sua simplicidade e resultado estético satisfatório

Associaçäo de pinos intrarradiculares pré-fabricados e cerômeros na restauraçäo de dentes tratados endodonticamente / Association of pre-fabricated intra-root posts and ceromers in the endodontically treated teeth restoration

O uso de pinos pré-fabricados em dentes tratados endodonticamente tem sido uma excelente alternativa, pois estes têm como principais vantagens o seu emprego relativamente simples e execuçäo com menor tempo de trabalho clínico, podendo ser realizado em única sessäo. O objetivo da restauraçäo de dentes tratados endodonticamente é reproduzir características naturais, devolvendo ao dente a estética e a funçäo mastigatória. Os autores descrevem a técnica de utilizaçäo do pino intrarradicular Unimetric© (Maillefer) e realizaçäo de uma coroa total com o sistema Artglass© (Kulzer)

Colagem de dente anterior fraturado: relato de caso clínico / Dental bonding of fractured anterior tooth: a clinical case report

Com o advento da técnica do condicionamento ácido do esmalte com Buonocore em 1955, e posterior surgimento das resinas compostas e sistemas adesivos, os dentes anteriores fraturados passaram a ser restaurados de uma forma mais conservadora, uma vez que menor quantidade de tecido dental sadio é desgastado durante o preparo, mais simples, rápida e estética