RESUMO
PURPOSE: To investigate the effect of adhesive type and long-term aging on the shear bond strength (SBS) between silica-based ceramics and composite cement (CC). MATERIALS AND METHODS: Lithium-silicate (LS), feldspathic (FD) and polymer-infiltrated ceramic (PIC) blocks were sectioned (10 x 12 x 2 mm) and divided into 24 groups considering the factors: "ceramics" (LS, FD, and PIC), "adhesive" (Ctrl: without adhesive; 2SC: 2-step conventional; 3SC: 3-step conventional; 1SU: 1-step universal), and "aging" (non-aged or aged [A]). After the surface treatments, CC cylinders (n = 15, Ø = 2 mm; height = 2 mm) were made and half of the samples were subjected to thermocycling (10,000) and stored in water at 37°C for 18 months. The samples were submitted to SBS testing (100 kgf, 1 mm/min) and failure analysis. Extra samples were prepared for microscopic analysis of the adhesive interface. SBS (MPa) data was analyzed by 3-way ANOVA and Tukey's test (5%). Weibull analysis was performed on the SBS data. RESULTS: All factors and interactions were significant for SBS (p<0.05). Before aging, there was no significant difference between the tested groups and the respective control groups. After aging, the LS_1SU (22.18 ± 7.74) and LS_2SC (17.32 ± 5.86) groups exhibited significantly lower SBS than did the LS_Ctrl (30.30 ± 6.11). Only the LS_1SU group showed a significant decrease in SBS after aging vs without aging. The LS_1SU (12.20) group showed the highest Weibull modulus, which was significantly higher than LS_2SC_A (2.82) and LS_1SU_A (3.15) groups. CONCLUSION: No type of adhesive applied after silane benefitted the long-term adhesion of silica-based ceramics to CC in comparison to the groups without adhesive.
Assuntos
Cerâmica , Colagem Dentária , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Dióxido de Silício , Dióxido de Silício/química , Cerâmica/química , Fatores de Tempo , Cimentos de Resina/química , Desenho Assistido por Computador , Propriedades de Superfície , Análise do Estresse Dentário , Cimentação/métodos , Porcelana Dentária/química , Humanos , Resinas Compostas/química , Cimentos Dentários/química , Compostos de Potássio/química , Silicatos de Alumínio/química , TemperaturaRESUMO
ABSTRACT Objective: This study aimed to evaluate the effectiveness of two methods of visual magnification (operating microscope and light head magnifying glass) for removal of composite flash around orthodontic metal brackets. Material and Methods: Brackets were bonded in the center of the clinical crown of sixty well-preserved human premolars. Half of the sample was bonded with conventional Transbond XT (3M Unitek TM, USA), whereas the other half was bonded with Transbond TM Plus Color Change (3M Unitek TM, USA). For each type of composite, the choice of method to remove the flash was determined by randomly distributing the teeth into the following subgroups: A (removal by naked eye, n = 10), B (removal with the aid of light head magnifying glass, under 4x magnification, n = 10), and C (removal with the aid of an operating microscope, under 40x magnification, n = 10). Brackets were debonded and teeth taken to a scanning electron microscope (SS-x-550, Shimadzu, Japan) for visualization of their buccal surface. Quantification of composite flash was performed with Image Pro Plus software, and values were compared by Kruskal-Wallis test and Dunn’s post-hoc test at 5% significance level. Results: Removal of pigmented orthodontic adhesive with the aid of light head magnifying glass proved, in general, to be advantageous in comparison to all other methods. Conclusion: There was no advantage in using Transbond TM Plus Color Change alone. Further studies are necessary to draw a more definitive conclusion in regards to the benefits of using an operating microscope.
RESUMO Objetivo: este estudo teve o objetivo de avaliar a eficácia de dois métodos de magnificação visual (microscópio cirúrgico e lupa de pala) para remoção da resina residual em torno de braquetes ortodônticos metálicos. Material e Métodos: os braquetes foram colados no centro da coroa clínica de 60 pré-molares humanos bem preservados. Metade da amostra foi colada com Transbond XT convencional (3M UnitekTM, EUA), enquanto a outra metade foi colada com TransbondTM Plus Color Change (3M-UnitekTM, EUA). Para cada tipo de resina, a escolha do método para remover o resíduo foi determinada por meio da distribuição aleatória dos dentes nos seguintes subgrupos: A (remoção a olho nu, n = 10), B (remoção com a ajuda de lupa de pala, sob uma ampliação de 4x, n = 10) e C (remoção com auxílio de um microscópio cirúrgico, sob uma ampliação de 40x, n = 10). Os braquetes foram descolados e os dentes, levados a um microscópio eletrônico de varredura (SS-X-550, Shimadzu, Japão) para visualização de sua superfície vestibular. A quantificação da resina residual foi realizada por meio do software Image Pro Plus, onde os valores foram comparados utilizando-se o teste de Kruskal-Wallis e o teste post-hoc de Dunn, ao nível de significância de 5%. Resultados: a remoção da resina ortodôntica pigmentada com o auxílio da lente de aumento de pala provou, em geral, ser mais vantajosa, em comparação aos outros métodos testados. Conclusão: não houve vantagem em se usar a TransbondTM Plus Color Change sozinha. Estudos adicionais são necessários para se chegar a uma conclusão definitiva sobre os benefícios da utilização de microscópio cirúrgico.
Assuntos
Humanos , Ortodontia Corretiva/métodos , Braquetes Ortodônticos , Cimentos Dentários/uso terapêutico , Ortodontia Corretiva/instrumentação , Dente Pré-Molar , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Colagem Dentária/instrumentação , Colagem Dentária/métodos , Microscopia/instrumentação , Microscopia/métodosRESUMO
O objetivo desta pesquisa in vitro foi avaliar a limpeza proporcionada pelo desbridamento no terço apical através da microscopia óptica e de varredura. Para isso, utilizaram-se cinquenta molares inferiores humanos, os quais depois de acessados foram impermeabilizados, esterilizados, contaminados com cepas de Enterococus faecalis (ATCC 29212), durante trinta e cinco dias. Posteriormente foram submetidos ao preparo químico-mecânico com as limas do sistema rotatório Protaper e desbridados com as limas #10 (G1); limas #15 (G2); limas #10 + medicação intracanal - MIC (G3); limas #15 + MIC (G4) e o controle positivo - sem desbridamento e sem MIC - (G5). Em seguida, os espécimes foram avaliados pelos métodos da microscopia óptica (clínica operatória) e microscopia eletrônica de varredura. O teste Kruskal-Wallis mostrou a eficiência do desbridamento, e verificou-se que houve diferença estatisticamente significante (p=0,000) entre os grupos G1 e o G2 no tocante ao aumento da eficácia do desbridamento radicular apical. Quanto às metodologias empregadas, observou-se que ambas são indicadas para avaliar a limpeza proporcionada pelo desbridamento, sendo que as análises através da MCO apresentaram imagens heterogêneas, enquanto a MEV imagens homogêneas. Pode-se concluir que o desbridamento foi eficaz na limpeza do terço apical em molares humanos, porém não houve diferença quanto ao calibre das limas #10 e #15. Os métodos de avaliação da microscopia óptica (clínica operatória) e microscopia eletrônica de varredura foram eficientes em visualizar a limpeza no terço apical...
The aim of this in vitro study was to evaluate the level of cleanliness achieved by debridement of the apical third of root canals by light and scanning microscopy. A total of 50 human mandibular molars were accessed, impermeabilized, sterilized and, subsequently inoculated with a strain of Enterococcus faecalis (ATCC 29212) for 35 days. They were then subjected to chemical-mechanical preparation with the following rotatory Protaper system files: Kerr files #10 (G1) and #15 (G2); Kerr files #10 + intracanal medication - MIC (G3); Kerr files #15 + MIC (G4); and positive controls without debridement or MIC (G5). The apical thirds of the canals were then examined by light clinical microscopy and scanning electron microscopy (SEM). The Kruskal-Wallis test showed the efficiency of the debridement, as verified by statistically significant differences (p=0.000) between groups G1 and G2 with regard to the increase in the effectiveness of the debridement apical radicular. Both light microscopy and SEM were suitable for assessing the cleanliness obtained by debridement. However, while the images seen under the light microscopy were heterogeneous, scanning electron microscopy yielded images that were homogenous. Debridement was efficient for cleansing the apical thirds of canals in human molars, with similar levels of cleanliness achieved with either Kerr files #10 or Kerr files #15. Both clinical microscopy and scanning electron microscopy allowed for adequate visualization for the evaluation of cleanliness in the apical third of the root canal...
Assuntos
Humanos , Ápice Dentário/anatomia & histologia , Dente Molar/anatomia & histologia , Desbridamento/métodos , Microscopia Eletrônica de Varredura/métodos , Tratamento do Canal Radicular , Odontometria/métodos , Estatísticas não Paramétricas , Técnicas In Vitro/métodosRESUMO
Objetivo: Avaliar a eficácia das manobras de desbridamento no preparo químico-mecânico (PQM) quanto a limpeza e desinfecção no terço apical em molares humanos. Material e método: Cinquenta raízes mesiais de molares inferiores humanos com dois canais radiculares foram inoculadas com E. faecalis e distribuídas aleatoriamente em cinco grupos (n=10). O PQM foi realizado com o sistema Protaper associado ao desbridamento com as limas Kerr #10 (G1 e G3) e as limas Kerr #15 (G2 e G4). O G5 representou o controle positivo, o qual foi submetido apenas ao PQM, sem receber o desbridamento. Outra variável foi o uso da medicação intracanal (MIC) à base de hidróxido de cálcio (Calen), que foi aplicada aos grupos G3 e G4. A irrigação foi feita com hipoclorito de sódio 2,5% e EDTA 17%. A análise da ação antimicrobiana se deu através da contagem das unidades formadoras de colônias (UFC). Resultado: Foram aplicados o Teste Kruskal-Wallis (nas análises imediatas) e o Teste Mann-Whitney (nas análises mediatas), ambos com p=0,01. A análise imediata ao PQM apresentou-se sem diferença estatística entre os grupos (p=0,11). No G4 (#15 + MIC), os resultados das coletas mediatas foram estatisticamente significantes (p=0,01). Conclusão: O desbridamento com as limas Kerr #10 e #15 não apresentou diferença significativa quanto à redução das colônias de E. faecalis quando comparado ao grupo em que não se realizou o desbridamento. Nos espécimes em que se aplicou a MIC, o desbridamento com a lima Kerr #15 (G4) foi mais eficiente do que a lima Kerr #10 (G3) em reduzir as UFC.
Aim: The aim of this in vitro study was to evaluate the efficacy of chemo-mechanical preparation (CMP) debridement procedures in regard to cleansing and disinfection of the apical third of human molar canals using different protocols. Material and method: Fifty mesial roots of human mandibular molars containing two canals were inoculated with E. faecalis strains and randomly allocated to five groups (n=10). CMP was carried out with the rotatory Protaper system associated with Kerr files #10 (G1 and G3) and #15 (G2 and G4). G5, the positive control, was subjected to CMP without debridement. Another variable studied was the use of calcium hydroxide-based temporary intracanal medication (Calen) prior to the chemo-mechanical performed in the G3 and G4 groups. Irrigation was performed with 2.5% sodium hypoclorite and 17% EDTA. Antimicrobial activity was quantified by counting the number of colony-forming units (CFU). Result: Kruskal-Wallis was used for immediate analyses and Mann-Whitney for mediate analyses both with a stipulated value of significance of p=0.01. In the imediate analyses following CMP there were no significant differences among the groups (p=0.11). In the G4 (#15 + MIC) the results of the mediate collections were statistically significant (p=0.01). Conclusion: Debridement with #10 and #15 Kerr files did not produce significant differences in regard to reduction of E. faecalis when compared to the positive control. In samples where Calen intracanal medication was used debridement with #15 Kerr files was more efficient in reducing the number of CFUs than #10 Kerr files.
Assuntos
Humanos , Técnicas In Vitro , Enterococcus faecalis , Estatísticas não Paramétricas , Desbridamento , Microbiologia , Dente Molar , Irrigantes do Canal Radicular , Hipoclorito de Sódio , Hidróxido de Cálcio , DesinfecçãoRESUMO
OBJECTIVE:: This study aimed to evaluate the effectiveness of two methods of visual magnification (operating microscope and light head magnifying glass) for removal of composite flash around orthodontic metal brackets. MATERIAL AND METHODS:: Brackets were bonded in the center of the clinical crown of sixty well-preserved human premolars. Half of the sample was bonded with conventional Transbond XT (3M Unitek TM, USA), whereas the other half was bonded with Transbond TM Plus Color Change (3M Unitek TM, USA). For each type of composite, the choice of method to remove the flash was determined by randomly distributing the teeth into the following subgroups: A (removal by naked eye, n = 10), B (removal with the aid of light head magnifying glass, under 4x magnification, n = 10), and C (removal with the aid of an operating microscope, under 40x magnification, n = 10). Brackets were debonded and teeth taken to a scanning electron microscope (SS-x-550, Shimadzu, Japan) for visualization of their buccal surface. Quantification of composite flash was performed with Image Pro Plus software, and values were compared by Kruskal-Wallis test and Dunn's post-hoc test at 5% significance level. RESULTS:: Removal of pigmented orthodontic adhesive with the aid of light head magnifying glass proved, in general, to be advantageous in comparison to all other methods. CONCLUSION:: There was no advantage in using Transbond TM Plus Color Change alone. Further studies are necessary to draw a more definitive conclusion in regards to the benefits of using an operating microscope.
Assuntos
Cimentos Dentários/uso terapêutico , Braquetes Ortodônticos , Ortodontia Corretiva/métodos , Dente Pré-Molar , Colagem Dentária/instrumentação , Colagem Dentária/métodos , Humanos , Técnicas In Vitro , Microscopia/instrumentação , Microscopia/métodos , Microscopia Eletrônica de Varredura , Ortodontia Corretiva/instrumentaçãoRESUMO
PURPOSE: To evaluate the effect of different endodontic irrigating solutions on the micro push-out bond strength of a fiber glass dowel. MATERIAL AND METHODS: Seventy 16-mm long root segments of bovine incisors were prepared and randomly assigned to 7 groups (n=10) according to the type of irrigating solution used prior to the cementation of the intra-radicular fiber glass dowels: G1: 5.25% NaOCl + 17% EDTA; G2: 5.25% NaOCl; G3: 17% EDTA; G4: 2% chlorhexidine gel; G5: 70% alcohol; G6: 11.5% polyacrylic acid; and G7: saline (control). After treatment of intracanal dentin, the glass fibre dowels were cemented with self-adhesive resin cement (RelyX Unicem). Six slices with the thickness of 1.00 ± 0.05 mm were obtained from each tooth at the coronal, middle and apical root thirds (2 slices per third) using a low-speed saw. Micro push-out tests were performed at a crosshead speed of 0.5mm/min and the data (MPa) were analyzed statistically by ANOVA and Tukey's and Dunnett's tests. RESULTS: There were statistically significant differences (p<0.0001) among the irrigating solutions, but no significant difference (p=0.0591) was found among the root thirds. G5 presented the highest bond strength mean of all groups (p<0.0001). The use of 70% alcohol increased the adhesion values by 53% compared to the group control. CONCLUSION: The use of 70% alcohol increased the bond strength of the fiber glass dowel to the dentin walls. However, the push-out bond strength between the dowel and the root dentin was not affected by the root third (coronal, middle and apical).
RESUMO
Objetivo: Esse estudo avaliou quatro sistemas endodônticos mecanizados, ProTaper Universal, K3 Endo, Twisted file, (rotatórios) e Endo - Eze TiLOS(oscilatório) para verificar e medir as alterações na anatomia original do canal radicular e desvios nos terços cervical,médio e apical. Material e Método: Foram utilizadas 60 raízes mésio-vestibulares de molares inferiores extraídos de humanos para coleta de medições de ângulos e classificação de Schneider. Os espécimes foram incluídos em resina de Éster vinil e montadas em muflas de Teflon, seccionadas transversalmente nos terços cervical,médio e apical para posterior fotografia usando-se câmera digital Cyber Shot DSC-TX10,acoplada à um microscópio 3101XY DFVasconcelos com 40× de aumento para se mensurar a àrea da secção anatômica transversal do canal radicular utilizando o programa AutoCAD 2008, comparando as àreas pré e pós instrumentação. Todos os espécimes ajustados na mufla foram radiografados de maneira padronizada para permitir a avaliação do ângulo de Schneider pré e pós-instrumentação.Uma vez coletados os dados,os mesmos foram comparados estatisticamente usando-se o programa BioEstat 5.0. Resultado: A análise dos resultados mostrou que no terço cervical os sistemas rotatórios foram mais eficazes que o sistema oscilatório Endo-Eze TiLOS,com diferenças estatisticamente significantes (p ≤ 0,05). As alterações anatômicas relativas ao desvio nos terços apical e médio foram similares, mas apicalmente o sistema ProTaper promoveu mais desvios quando se avaliou o ângulo de Schneider pré e pós instrumentação (p ≤ 0,05). Conclusão: Utilizando-se a alteração do ângulo de Schneider e a diferença entre área dentinária inicial (antes do preparo) e final (pós-preparo), concluiu-se que todos os sistemas causaram desvio na anatomia original do canal radicular.
Objective: This study evaluated four mechanized Endodontic systems, ProTaper Universal, K3 Endo, Twisted file (rotary) and the oscillatory reciprocating system Endo - Eze TiLOS, in order to verify and measure alterations in original anatomy with deviations at cervical, medium and apical root canal thirds. Material and Method: It was used MB root canals of 60 extract human lower molars, to produce a line of severe angles, according to the classification of Schneider. Samples were included in Ester vinyl resin, mounted in the Teflon Furnace, transversally sectioned at the cervical, middle and apical thirds, which were subsequently photographed using a digital camera Cyber Shot DSC-TX10,attached to an operating microscope 3101XY DFVasconcelos with 40× magnification in order to measure the anatomical transversal area of the root canal, using the software AutoCAD 2008, comparing pre and post-instrumentation. All samples assembled in the Furnace also were submitted to x-ray in a standardized way to enable the comparison of the angle of Schneider pre-and post-instrumentation. Once collected the data, they were compared statistically using the program BioEstat 5.0. Result: The analysis of the results showed that in the cervical third, rotary systems were more effective than Endo-Eze TiLOS System with statistically significant differences (p ≤ 0,05). Apical and middle third changes in anatomy were similar, but apically, the ProTaper system caused more deviations when comparing the angle of Schneider,and areas before and after instrumentation(p ≤ 0,05). Conclusion: It was concluded that all the systems caused alteration in the original anatomy of the root canal when parameters as angle of Schneider and areas before and after preparation were used.
Assuntos
Tratamento do Canal Radicular , Tratamento do Canal Radicular/instrumentação , Cavidade Pulpar/anatomia & histologia , Endodontia , Dente MolarRESUMO
This in vitro study evaluated both the antimicrobial activity and the root canal cleaning ability of plant extracts used in irrigation solutions. The antimicrobial activities of the aroeira-da-praia (Schinus terebintifolius Raddi) and the quixabeira (Syderoxylum obtusifolium Roem & Schult) hydroalcoholic extracts, of 2.5% sodium hypochlorite (NaOCl) and of 0.12% chlorhexidine (positive control) against Enterococcus faecalis were tested with the agar well diffusion method. The level of root canal cleanliness was examined by scanning electron microscopy (SEM). Twenty one single-rooted human teeth were divided into three groups according to the irrigation solution applied: 1) 50% aroeira-da-praia; 2) 50% quixabeira and 3) a combination of 2.5% sodium hypochlorite + 17% EDTA. All solutions tested demonstrated antimicrobial activity against Enterococcus faecalis. The SEM analysis revealed that higher and lower degrees of surface cleaning were observed, in the three groups, respectively for the coronal and apical thirds, in that quixabeira showed the greatest efficiency in removing the smear layer in the apical third. All the agents tested presented antimicrobial activity against E. faecalis. None, however, was able to completely remove the smear layer of the dentinal surface in the different thirds of the root canal. The results suggest that the analyzed plant extracts may represent a new therapeutic option in the list of alternative agents available for endodontic treatment.
Assuntos
Humanos , Anacardiaceae/química , Anti-Infecciosos/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Irrigantes do Canal Radicular/farmacologia , Clorexidina/química , Dentina/efeitos dos fármacos , Ácido Edético/química , Microscopia Eletrônica de Varredura , Camada de Esfregaço , Estatísticas não Paramétricas , Propriedades de Superfície , Hipoclorito de Sódio/químicaRESUMO
This in vitro study evaluated both the antimicrobial activity and the root canal cleaning ability of plant extracts used in irrigation solutions. The antimicrobial activities of the aroeira-da-praia (Schinus terebintifolius Raddi) and the quixabeira (Syderoxylum obtusifolium Roem & Schult) hydroalcoholic extracts, of 2.5% sodium hypochlorite (NaOCl) and of 0.12% chlorhexidine (positive control) against Enterococcus faecalis were tested with the agar well diffusion method. The level of root canal cleanliness was examined by scanning electron microscopy (SEM). Twenty one single-rooted human teeth were divided into three groups according to the irrigation solution applied: 1) 50% aroeira-da-praia; 2) 50% quixabeira and 3) a combination of 2.5% sodium hypochlorite + 17% EDTA. All solutions tested demonstrated antimicrobial activity against Enterococcus faecalis. The SEM analysis revealed that higher and lower degrees of surface cleaning were observed, in the three groups, respectively for the coronal and apical thirds, in that quixabeira showed the greatest efficiency in removing the smear layer in the apical third. All the agents tested presented antimicrobial activity against E. faecalis. None, however, was able to completely remove the smear layer of the dentinal surface in the different thirds of the root canal. The results suggest that the analyzed plant extracts may represent a new therapeutic option in the list of alternative agents available for endodontic treatment.
Assuntos
Anacardiaceae/química , Anti-Infecciosos/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Irrigantes do Canal Radicular/farmacologia , Clorexidina/química , Dentina/efeitos dos fármacos , Ácido Edético/química , Humanos , Microscopia Eletrônica de Varredura , Camada de Esfregaço , Hipoclorito de Sódio/química , Estatísticas não Paramétricas , Propriedades de SuperfícieRESUMO
CONTEXT: The effect of different curing units on bond strength of orthodontic brackets is still unclear when utilizing nanofilled composites in comparison with traditional Transbond-XT. AIM: To evaluate the influence of two adhesive promoters and two curing-light units on the shear bond strength (SBS) of orthodontic brackets. SETTINGS AND DESIGN: The factors under study were adhesive promoters (nanofilled composite - Filtek-Z350 flowable restorative and conventional orthodontic adhesive - Transbond XT) and curing-light units (halogen lamp - Ultralux and LED device - Radii-Call). MATERIAL AND METHODS: Forty lower bovine incisors were utilized. The teeth were distributed in four groups (n = 10) according to the combination between adhesive promoters and curing-light units. Scotchbond Multipurpose-Plus and Transbond-XT primer were used to bond Filtek-Z350 Flowable Restorative and Transbond-XT, respectively. After storage in distilled water for 24 h, the brackets were subjected to SBS test at a speed of 0.5 mm/min until bracket debonding. The Adhesive Remnant Index (ARI) was assigned at fractured specimens. STATISTICAL ANALYSIS USED: Analysis of variance and Tukey test were utilized. The Kruskal-Wallis test was used to compare ARI scores between the groups (p<0.05). RESULTS: There was statistically significant difference between the adhesive promoters tested. Transbond-XT showed higher SBS means than Filtek-Z350. There was no statistically significant difference between both curing-light units tested in this study, neither between ARI scores. CONCLUSIONS: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.
Assuntos
Resinas Compostas/química , Lâmpadas de Polimerização Dentária/classificação , Colagem Dentária , Braquetes Ortodônticos , Cimentos de Resina/química , Condicionamento Ácido do Dente/métodos , Adesividade , Animais , Bovinos , Análise do Estresse Dentário/instrumentação , Cura Luminosa de Adesivos Dentários/instrumentação , Nanocompostos/química , Ácidos Fosfóricos/química , Polimerização , Distribuição Aleatória , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Fatores de Tempo , Água/químicaRESUMO
Aim: This study evaluated both smear layer removal and reduction of Enterococcus faecalis after instrumentation with ultrasonic irrigation. Methods: Root canals were experimentally inoculated with E. faecalis for 20 days and microbiological samples were collected before and after chemomechanical preparation by using sterilized absorbent paper points. The irrigation solutions used were NaOCl 2.5% and EDTA 17%. In Group 1 (G1), conventional irrigation was used, whereas in Group 2 (G2) ultrasonic irrigation was performed. In group 3 (control), root canals were irrigated with distilled water. The samples were inoculated in BHI broth and turbidity was observed after 48 h to evaluate the reduction in the number of bacteria. Residual smear layer was examined by scanning electron microscopy (SEM). Results: The results showed no significant differences between ultrasonic and conventional irrigation. Conclusions: It was concluded that the level of disinfection and cleanliness of root canals achieved with ultrasonic irrigation is comparable to that obtained by conventional methods.
Assuntos
Irrigantes do Canal Radicular , Ultrassom , Camada de Esfregaço , Enterococcus faecalisRESUMO
Rehabilitation of edentulous patients has been a constant concern in dentistry. Several studies have reported a reduction in the masticatory function in these patients. Osseointegrated implants have been used in order to obtain better masticatory efficiency, but more studies are needed to confirm these results. Aim: To evaluate the masticatory function of patients with conventional dentures and implant-supported dentures. Methods: A double-blinded controlled clinical study was conducted. The sample was composed of 60 patients divided into three groups: G1 with 20 patients with conventional upper (maxillary) and lower (mandibular) complete dentures, G2 with 20 patients with mandibular overdentures and upper (maxillary) complete dentures, and G3 with 20 patients with lower fixed implant-supported complete dentures (protocol). Objective data were collected through the masticatory efficiency test performed by the colorimetric method with the beads, in which capsules of a synthetic material enclosing fuchsine-containing granules were used. Results: A statistically significant difference was found for masticatory efficiency between groups G1 and G2 (pd"0.05) and between G1 and G3 (pd"0.05), and there was no statistically significant difference between G2 and G3 (pe"0.05). Conclusions: The results suggest that placement of osseointegrated implants in complete denture wearers improves their masticatory efficiency.
Assuntos
Humanos , Masculino , Feminino , Boca Edêntula , Prótese Total , MastigaçãoRESUMO
O objetivo dessa revisão foi relatar uma visão geral e descritiva a respeito das propriedades de duas soluções irrigadoras, a solução de hipoclorito de sódio e de clorexidina com diferentes concentrações, utilizadas no tratamento de canais radiculares. Uma solução irrigadora considerada ideal deve apresentar ação antimicrobiana, dissolver resíduos teciduais, promover molhamento com finalidade de facilitar a instrumentação, e apresentar biocompatibilidade com os tecidos adjacentes. O hipoclorito de sódio utilizado em diferentes concentrações para limpeza de canais radiculares tem sido a solução de escolha entre os profissionais por apresentar ação antimicrobiana e atuar como solvente tecidual. Porém, atualmente, a clorexidina vem sendo muito utilizada como solução irrigadora devido a propriedades específicas que viabilizam sua utilização, tais como substantividade, efetividade antimicrobiana, e baixa toxicidade. Desse modo concluí-se que a solução de clorexidina com diferentes concentrações se apresenta como uma possível alternativa de solução irrigadora para o tratamento de canais radiculares.
The objective of this review was reporting an overview about the properties of two irrigating solutions, solution of sodium hypochlorite and chlorhexidine, used in the treatment of root canals. A solution must submit irrigating antimicrobial action, dissolve waste tissue, promote wetting to facilitate the instrumentation, and present biocompatibility with the adjacent tissues. The sodium hypochlorite used in different concentrations has been the solution of choice among professionals by presenting antimicrobial action and act as a solvent tissue. However, today, chlorhexidine has been widely used as an irrigating solution due to specific properties that enable its use, such as substantivity, antimicrobial effectiveness, and low toxicity. Thus the solution of chlorhexidine with different concentrations is presented as an alternative to irrigating solution for the treatment of root canals.
RESUMO
A síndrome da combinação é observada em pacientes que usam prótese total (PT) superior e prótese parcial removível (PPR) de extremo livre inferior. Essa síndro-me tem como principais características: perda óssea da região anterior do rebordo superior, extrusão dos dentes naturais anteriores inferiores, aumento das tuberosidades, perda óssea da região posterior do arco inferior sob a base da P.P.R. e hiperplasia papilar da mucosa do palato duro. Apesar de ter sido citada na literatura desde 1972 e existirem alternativas de tratamento e técnicas adequadas de moldagem que podem favorecer os pacientes portadores de tal síndrome, a aplicabilidade dessas técnicas não tem sido universal na prática clínica. Objetivo: O objetivo deste trabalho foi avaliar o conhecimento e aplicabilidade que os profissionais do estado do Rio Grande do Norte detêm a respeito de tal síndrome. Métodos: Para isso, um questionário com 14 questões foi aplicado aos especialistas e professores de prótese do estado. Resultados: Os resultados mos-traram que a maior parte dos profissionais (53%) conhece a teoria e realiza atendimentos nesses pacientes com critérios específicos. A síndrome da combinação está presente na clínica diária em 75% dos profissionais avaliados. Observou-se também que 61% dos profis-sionais acreditam conhecer uma técnica de moldagem especifica que pode beneficiar o tratamento, mas nenhum soube responder qual técnica seria a mais indicada. Conclusões: Concluiu-se que há um grande número de profissionais que dizem conhecer a respeito da síndrome da combinação, no entanto a maior parte não conhece todos os sinais que a caracterizam nem utiliza uma técnica de moldagem específica para esta situação clínica.
RESUMO
INTRODUÇÃO: Muitos estudos têm sido realizados para avaliar o potencial terapêutico das plantas. OBJETIVO: Este estudo teve como objetivo avaliar a ação antimicrobiana dos extratos etanólicos da aroeira-da-praia (Schinus terebinthifolius Raddi), da aroeira-do-sertão (Astronium urundeuva [Fr. All.] Engl.), da ameixa-do-mato (Ximenia americana L.), da quixabeira (Syderoxylum obtusifolium [Roem et Schult.]) e do hipoclorito de sódio (NaOCl a 2,5 por cento), contra o Enterococcus faecalis (ATCC 29212). METODOLOGIA: Foi realizado teste de difusão em ágar, pelo método do poço, utilizando-se como controle positivo a clorexidina a 0,12 por cento. Os microrganismos foram semeados em caldo BHI e incubados a 37ºC por 24 horas. Posteriormente, as suspensões microbianas foram semeadas em placas Petri, com ágar Mueller Hinton, sendo confeccionados seis poços equidistantes. As placas foram mantidas à temperatura ambiente por 2 horas, para ocorrer a pré-difusão das substâncias, e incubadas a 37ºC por 48 horas. Foram feitas as análises e medições dos halos de inibição em triplicata e os resultados foram analisados estatisticamente (teste de análise de variância [ANOVA]). RESULTADOS: A quixabeira apresentou os menores halos de inibição (teste t, p < 0,05); por outro lado, a clorexidina a 0,12 por cento e os extratos vegetais aroeira-do-sertão e aroeira-da-praia, na concentração 100 por cento, induziram halos maiores do que o NaOCl a 2,5 por cento, com diferença estatisticamente significativa (teste t, p < 0,05). A aroeira-do-sertão e a aroeira-da-praia apresentaram halos de inibição contra o Enterococcus faecalis superiores aos demais extratos vegetais testados, em todas as concentrações. CONCLUSÃO: Todas as substâncias analisadas apresentaram atividade antimicrobiana contra o Enterococcus faecalis, sugerindo que podem representar substâncias alternativas no tratamento endodôntico.
INTRODUCTION: Several studies have evaluated the therapeutic benefits of plants. OBJECTIVE: The aim of this study was to evaluate the antimicrobial activity of ethanol extracts of pepper tree (Schinus terebinthifolius Raddi), aroeira (Astronium urundeuva [Fr. All.] Engl.), Olacaceae (Ximenia americana L.), quixaba (Syderoxylum obtusifolium [Roem et Schult.]), and sodium hypochlorite (NaOCl 2.5 percent) against Enterococcus faecalis (ATCC 29212). METHODS: The agar diffusion test was performed and 0.12 percent chlorhexidine was applied as positive control. The microorganisms were allowed to grow in a brain-heart infusion broth (BHI) and incubated at 37ºC for 24 hours. Subsequently, the microbial suspensions were seeded on Petri dishes containing Mueller Hinton agar, and six equidistant wells were made. The plates were kept at room temperature for 2 hours for the pre-diffusion of substances, and incubated at 37ºC for 48 hours. The analysis and measurement of inhibition zones were performed in triplicate, and the results were statistically analyzed (ANOVA test). RESULTS: Quixaba produced the smallest inhibition zones (t test, p < 0.05). On the other hand, 0.12 percent chlorhexidine, herbal extracts of pepper tree and aroeira at 100 percent concentration induced larger inhibition zones in comparison with 2.5 percent NaOCl, with statistically significant difference (t test, p < 0.05). At all concentrations, both pepper tree and aroeira showed a higher inhibition zone against Enterococcus faecalis in comparison with the other plant extracts tested. CONCLUSION: All the substances analyzed showed antimicrobial activity against E. faecalis. Therefore , they may represent alternative substances in endodontic treatment.
RESUMO
Purpose: This study evaluated the flow rate of the Acroseal, AH Plus, Endomethasone N, Sealapex, and ActiV GP according to the standards of the ISO specification 6876/2001. Methods: A volume of 0.05 mL of the cement mixed according to the manufacturer's recommendations was placed on a glass plate. At 180±5 s after the commencement of mixing, the second glass plate was placed on top of the sealer, followed by the weight of mass approximately 100 g to make a total mass on the plate of 120±2 g. Ten min after the start of mixing, the weight was removed and the value of the diameter of the compressed disc of sealer was measured. The mean of three such determinations for each sealer was taken as the flow of the material. The mean values were compared using ANOVA and Tukey's tests. Results: The results obtained were: Acroseal 21.24 mm, AH Plus 22.72 mm, ActiV GP 24.90 mm, Endomethasone N 18.76 mm, and Sealapex 25.15 mm. Conclusion: Only the Endomethasone N did not conform to ISO Specification that requires that a sealer shall have a diameter of not less than 20 mm. The Sealapex achieved the greatest flow, but it did not differ from Activ GP and AH Plus (P>0.5).
Objetivo: Este estudo avaliou o escoamento do Acroseal, AH Plus, Endomethasone N, Sealapex e ActiV GP de acordo com a especificação ISO 6876/2001. Metodologia: Um volume de 0,05 mL do cimento manipulado de acordo com as recomendações do fabricante foi colocado numa placa de vidro. Aos 180±5 s após o início da espatulação, uma segunda placa de vidro foi colocada sobre o cimento, seguida por um peso de massa de 100 g para fazer um total de 120±2 g. Dez minutos após o começo da manipulação o peso foi removido e o valor do diâmetro do disco de cimento foi mensurado. A média de 3 mensurações para cada cimento foi tomada como o escoamento do material. Os dados foram comparados estatisticamente pelos testes ANOVA e Tukey. Resultados: Os escoamentos obtidos foram: Acroseal 21.,4 mm, AH Plus 22,72 mm, ActiV GP 24,90 mm, Endomethasone N 18,76 mm e Sealapex 25,15 mm. Conclusão: Apenas o Endomethasone N não se enquadrou na especificação ISO a qual requer que o cimento tenha um diâmetro não inferior a 20 mm. O Sealapex alcançou o melhor escoamento, mas não foi estatisticamente diferente do Activ GP e AH Plus (P>0,05).
Assuntos
Cimentos Dentários/farmacocinética , Obturação do Canal RadicularRESUMO
Aim: This study evaluated the morphological changes caused by internal bleaching agents on dentin surface. Methods: Twenty crowns of bovine incisors were cut into slabs that were randomly distributed in six experimental groups (n = 5), according to the bleaching agent used: G1 sodium perborate + water, G2 sodium perborate + 2% chlorhexidine gel, G3 sodium perborate + 30% hydrogen peroxide, G4 30% hydrogen peroxide, G5 37% carbamide peroxide and G6 gel base without carbamide. Two Control Groups were used: C1 with distilled water and C2 with 2% chlorhexidine gel. The specimens were immersed in the respective test bleaching agent and incubated at 37 °C for seven days. Following, they were prepared for scanning electron microscopy and five images from each tooth segment were recorded and analyzed for surface morphological alterations, by three previously calibrated examiners. Inter-examiner agreement was verified using the Kappa test. The rank averages obtained for the groups were subjected to Kruskal-Wallis analysis of variance at 5% significance level. Results: The analysis of the scores obtained indicated that all tested materials caused some morphological alteration on dentin, except for sodium perborate + water (G1) and Control Groups 1 and 2. Hydrogen peroxide and carbamide peroxide caused significantly more severe alterations (p < 0.05) to dentin structure, than the other bleaching agents evaluated. Conclusions: Sodium perborate-based pastes seemed to be the most harmless agent to dentinstructures in non-vital tooth bleaching, while hydrogen peroxide solutions and carbamide peroxide agents caused the greatest alterations.
Assuntos
Animais , Bovinos , Dentina/anatomia & histologia , Dentina , Dentina/química , Clareamento Dental , Microscopia Eletrônica de Varredura , Peróxido de Hidrogênio/química , Estatísticas não ParamétricasRESUMO
The aim of this study was to assess the influence of a fluoridated medium on the mechanical properties of an internal hexagon implant-abutment set, by means of compression, mechanical cycling and metallographic characterization by scanning electronic microscopy. Five years of regular use of oral hygiene with a sodium fluoride solution content of 1500 ppm were simulated, immersing the samples in this medium for 184 hours, with the solutions being changed every 12 hours. Data were analyzed at a 95 percent confidence level with Fisher's exact test. After the action of fluoride ions, a negative influence occurred in the mechanical cycling test performed in a servohydraulic machine (Material Test System-810) set to a frequency of 15 Hz with 100,000 cycles and programmed to 60 percent of the maximum resistance of static compression test. The sets tended to fracture by compression on the screw, characterized by mixed ruptures with predominance of fragile fracture, as observed by microscopy. An evidence of corrosion by pitting on sample surfaces was found after the fluoride ions action. It may be concluded that prolonged contact with fluoride ions is harmful to the mechanical properties of commercially pure titanium structures.
RESUMO
The aim of this study was to assess the influence of a fluoridated medium on the mechanical properties of an internal hexagon implant-abutment set, by means of compression, mechanical cycling and metallographic characterization by scanning electronic microscopy. Five years of regular use of oral hygiene with a sodium fluoride solution content of 1500 ppm were simulated, immersing the samples in this medium for 184 hours, with the solutions being changed every 12 hours. Data were analyzed at a 95% confidence level with Fisher's exact test. After the action of fluoride ions, a negative influence occurred in the mechanical cycling test performed in a servohydraulic machine (Material Test System-810) set to a frequency of 15 Hz with 100,000 cycles and programmed to 60% of the maximum resistance of static compression test. The sets tended to fracture by compression on the screw, characterized by mixed ruptures with predominance of fragile fracture, as observed by microscopy. An evidence of corrosion by pitting on sample surfaces was found after the fluoride ions action. It may be concluded that prolonged contact with fluoride ions is harmful to the mechanical properties of commercially pure titanium structures.
RESUMO
El objetivo de este trabajo fue evaluar la influencia de un medio fluorado en la fractura del conjunto implante/pilar en sistemas de hexágono externo. La fractura fue producida por fatiga de bajo ciclo, analizándose la superficie mediante microscopía electrónica de barrido (MEB). Se simularon cinco años de uso regular de productos de higiene oral conteniendo 1.500 ppm de NaF, pH 6,8. Este contacto prolongado con fluoruros influenció negativamente el desempeño a la fatiga de bajo ciclo realizada en una máquina de ensayos mecánicos MTS-810 programada a 100.000 ciclos, 15 Hz, con 30 por ciento y 60 por ciento de valores de stress máximos en tracción y comprensión no axial, respectivamente. Al análisis a través del MEB reveló signos de corrosión superficial del titanio en el grupo test. Se concluyó que el contacto prolongado con fluoruro afecta el desempeño mecánico y puede contribuir a desarrollar fracturas, cuando se producen condiciones de sobrecarga sobre estructuras de titanio, lo cual puede disminuir la durabilidad de los componentes.