Efeito de diferentes irrigantes finais na resistência união de um cimento de silicato de cálcio: estudo in vitro / Effect of different final irrigants on the bond strength of a calcium silicate cement : in vitro study

Objetivo: Este estudo teve como objetivo avaliar a resistência de união do cimento Biodentine® à dentina radicular após a utilização de diferentes irrigantes finais. Método: Vinte dentes humanos extraídos tiveram seu terço médio radicular cortado em fatias que foram submersas em hipoclorito de sódio 2,5% e posteriormente divididas aleatoriamente em 4 grupos experimentais (n=15) conforme o irrigante final utilizado (1) água destilada (controle), (2) QMixTM, (3) ácido cítrico 10%, (4) EDTA 17%. Após a imersão na substância teste as amostras foram preenchidas com o cimento Biodentine e imersas em solução salina tamponada com fosfato (PBS) por um período de 7 dias. O teste de push out foi realizado e os valores de resistência de união em Mpa foram obtidos. Os dados foram analisados pelos testes de Kruskal Wallis e Studend- Newman-Keuls. Resultados: Os piores valores de união foram obtidos após a utilização do EDTA enquanto a água destilada, o QMix e o ácido cítrico apresentaram resultados estatisticamente semelhantes entre si. Conclusão: A remoção da smear layer não resultou em melhora nos resultados de união do cimento Biodentine.(AU)

Objective: This study aimed to evaluate the bond strength of Biodentine® cement to root dentin after the use of different final irrigants. Method: Twenty extracted human teeth had their middle root third cut into slices that were submerged in 2.5% sodium hypochlorite and then randomly divided into 4 experimental groups (n=15) according to the final irrigant used (1) distilled water (control), (2) QMixTM, (3) 10% citric acid, (4) 17% EDTA. After immersion in the test substance the samples were filled with Biodentine cement and immersed in phosphate buffered saline (PBS) for a period of 7 days. The push out test was performed and the bond strength values in MPa were obtained. The data were analyzed by Kruskal Wallis and Studend- Newman-Keuls tests. Results: The worst bond values were obtained after using EDTA while distilled water, QMix and citric acid showed statistically similar results to each other. Conclusion: Removal of the smear layer did not result in improved bonding results of Biodentine cement.(AU)

Root filling quality and bond strength of endodontic sealers to human and bovine dentin / Qualidade da obturação e resistência de união de cimentos endodônticos à dentina humana e bovina

Objetivo: Este estudo teve como objetivo comparar a qualidade da obturação e a resistência de união de dois cimentos endodônticos, AH Plus e Bio-C Sealer, em dentes humanos e bovinos. Métodos: Os canais radiculares de 60 dentes unirradiculares [30 humanos (H) e 30 bovinos (B)] foram preparados e obturados por condensação lateral da guta-percha e AH Plus (grupos AP-H e AP-B) ou Bio-C Sealer (grupos BC-H e BC-B). Seis fatias de 1,5 mm de espessura foram obtidas de cada raiz. Os espécimes foram observados em estereomicroscópio para avaliar a qualidade da obturação, considerando possíveis espaços vazios no material obturador. Posteriormente, as fatias radiculares foram avaliadas em termos de resistência de união por push-out e modo de falha. Os dados foram analisados pelos testes de Mann-Whitney e coeficientes de correlação de Spearman (α=5%). Resultados: A qualidade de obturação fornecida por AP e BC foi semelhante em ambos os substratos de dentina. No entanto, ao comparar dentes humanos e bovinos, os escores de espaços vazios foram maiores nas amostras bovinas, para ambos os cimentos. AP teve maior resistência de união à dentina humana e bovina do que BC. No entanto, não houve diferença significativa na resistência de união entre os substratos dentinários, para ambos os cimentos testados. Além disso, houve uma correlação positiva e moderada entre os valores de resistência de união de dentes humanos e bovinos. O modo de falha misto foi o mais prevalente. Conclusão: AP e BC fornecem qualidade de obturação semelhante, mas o primeiro apresenta maiores valores de resistência de união à dentina humana e bovina. A utilização de dentes bovinos como substitutos de amostras humanas parece ser adequada em estudos relacionados à resistência de união, mas não naqueles que testam a qualidade da obturação endodôntica.(AU)

Objective: This study aimed to compare the filling quality and bond strength of two endodontic sealers, AH Plus and Bio-C Sealer, in human and bovine teeth. Methods: The root canals of 60 [30 human (H) and 30 bovine (B)] single-rooted teeth were prepared and filled by lateral condensation of gutta-percha and AH Plus (groups AP-H and AP-B) or Bio-C Sealer (groups BC-H and BC-B). Six 1.5-mm-thick slices were obtained from each root. The specimens were observed under a stereomicroscope to assess filling quality, considering possible voids within the filling material. Subsequently, root slices were evaluated in terms of push-out bond strength and failure mode. Data were analyzed by Mann-Whitney tests and Spearman correlation coefficients (α=5%). Results: The filling quality provided by AP and BC was similar in both dentin substrates. However, when comparing human and bovine teeth, void scores were greater in the bovine samples, for both sealers. AP had higher bond strength to human and bovine dentin than BC. However, there was no significant difference in bond strength between dentin substrates, for both sealers tested. Also, there was a positive and moderate correlation between the bond strength values of human and bovine teeth. The mixed failure mode was the most prevalent. Conclusion: AP and BC provide similar filling quality, but the first presents higher bond strength values to human and bovine dentin. The use of bovine teeth as substitutes for human samples seems adequate in studies related to bond strength, but not in those testing root canal filling quality.(AU)

Three-dimensional finite element analysis of cement flow in abutment margin-crown platform switching / 北京大学学报(医学版)

OBJECTIVE@#To analyze the cement flow in the abutment margin-crown platform switching structure by using the three-dimensional finite element analysis, in order to prove that whether the abutment margin-crown platform switching structure can reduce the inflow depth of cement in the implantation adhesive retention.@*METHODS@#By using ANSYS 19.0 software, two models were created, including the one with regular margin and crown (Model one, the traditional group), and the other one with abutment margin-crown platform switching structure (Model two, the platform switching group). Both abutments of the two models were wrapped by gingiva, and the depth of the abutment margins was 1.5 mm submucosal. Two-way fluid structure coupling calculations were produced in two models by using ANSYS 19.0 software. In the two models, the same amount of cement were put between the inner side of the crowns and the abutments. The process of cementing the crown to the abutment was simulated when the crown was 0.6 mm above the abutment. The crown was falling at a constant speed in the whole process spending 0.1 s. Then we observed the cement flow outside the crowns at the time of 0.025 s, 0.05 s, 0.075 s, 0.1 s, and measured the depth of cement over the margins at the time of 0.1 s.@*RESULTS@#At the time of 0 s, 0.025 s, 0.05 s, the cements in the two models were all above the abutment margins. At the time of 0.075 s, in Model one, the gingiva was squeezed by the cement and became deformed, and then a gap was formed between the gingiva and the abutment into which the cement started to flow. In Model two, because of the narrow neck of the crown, the cement flowed out from the gingival as it was pressed by the upward counterforce from the gingival and the abutment margin. At the time of 0.1 s, in Model one, the cement continued to flow deep inside with the gravity force and pressure, and the depth of the cement over the margin was 1 mm. In Model two, the cement continued to flow out from the gingival at the time of 0.075 s, and the depth of the cement over the margin was 0 mm.@*CONCLUSION@#When the abutment was wrapped by the gingiva, the inflow depth of cement in the implantation adhesive retention can be reduced in the abutment margin-crown platform switching structure.

Índice de recurrencia de tumor de células gigantes con curetaje y cementación / Recurrence rate of giant-cell tumor treated by curettage and cementation

OBJETIVO Identificar la tasa de recurrencia de tumor de células gigantes (TCG) en pacientes tratados con curetaje y cementación con seguimiento mínimo de tres años. MATERIALES Y METODOS Cohorte retrospectiva y observacional de pacientes con diagnóstico de TCG en estadios 1 y 2 de Enneking tratados con curetaje intralesional y cementación entre 1981 y 2011. Se registraron edad, sexo, región anatómica, y tiempo de recurrencia. Se utilizó estadística descriptiva con medidas de tendencia central y medidas de dispersión (desviación estándar) para variables cuantitativas, y porcentajes para variables cualitativas. RESULTADOS Entre 1981 y 2011, se identificaron 375 casos de TCG, de los cuales 141 (37,6%) fueron tratados con este método. El seguimiento fue de 48 a 240 meses, y la edad, de 27 9 años; 45% de los pacientes eran mujeres, y 55%, varones, con una relación mujer:hombre de 1,2:1. El hueso más afectado fue la tibia (38%), seguida del fémur (32%), del húmero (16%), y del radio (10%). En 88,6%, la resección fue curetaje intralesional, y el resto, marginal. Hubo 15,7% de casos de TCG con fractura, y recidiva en 12,7%. DISCUSIÓN Se ha demostrado que este método de tratamiento reduce el riesgo de recurrencia por los efectos adyuvantes locales de la cementación acrílica. La recurrencia ocurre en los dos primeros años de seguimiento. Sin embargo, hay autores que respaldan que el margen quirúrgico es el único factor que influencia el riesgo de recurrencia local. La extensión extraósea del TCG no es contraindicación para curetaje intralesional y adyuvante con metilmetacrilato. CONCLUSIONES Reportamos tasa una de recurrencia similar a la de la literatura, siendo un recurso factible de reconstrucción de miembros

OBJETIVE To identify the recurrence rate of giant-cell tumor (GCT) in patients treated by curetage and adjuvant therapy with polymethil metacrylate with a minimum followup of 3 years. MATERIALS AND METHODS Observational and retrospective cohort with patients with diagnoses of Enneking stages 1 and 2 GCT treated through intralesional curetage and cementation between 1981 and 2011. Age, gender, anatomic location and relapse period were recorded. The data was analyzed with measures of central tendency and dispersion (standard deviation) for the quantitative variables, percentages for the qualitative variables. RESULTS Between 1981 and 2011 375 cases of GCT were identified, 141 (36.7%) of which were treated by this method. The follow-up ranged from 48 to 240 months, the age was of 27 9 years, 45% of the patients were female, and 55%, male, with a female: male ratio of about 1.2:1. The tibia was the most frequent affected bone (38%), followed by the femur (32%), the humerus (16%), and the radius (10%). The resection thecnique was intralesional curetage in about 88.6% of the cases, and marginal resection in the remaining cases. Pathologic fracture was present in approximately 15.7%, and recurrence occurred in approximately 12.7%. DISCUSSION We demonstrated that this treatment method decreases the risk of recurrence due to the local adjuvant effects of acrylic cementation. Recurrence events occur in the first two years after resection. However, some authors defend that the surgical margin is the only factor that influences the risk of local recurrence. The extraosseus extension of GCT is not a contraindication to perform intralesional curetage or to prescribe the adjuvant treatment with polymethyl metacrylate. CONCLUSIONS We reported a recurrence rate similar to that of the literature, and this is a feasible resource for limb reconstruction

Estudio comparativo entre coronas, endocoronas y endocoronas con ausencia de una pared axial ante fuerzas de tracción / Comparative study between crown, endocrown and endocrown without one axial wall after tensile strength

Introducción: Las alternativas de tratamiento de órganos dentales con gran destrucción en su estructura varían, no sólo por el material de restauración, sino también por el valor económico y estético. Dentro de las alternativas existe: corona convencional, endocorona cuyo objetivo principal es la elaboración de una restauradora que evita la colocación de postes intraconducto y endocorona con ausencia de una pared axial (EPA) que se realiza cuando una pared, mesial, distal, vestibular o palatina está ausente. Objetivo: Verificar si la endocorona EPA se comporta de igual manera que las coronas convencionales y endocoronas al medir su resistencia ante fuerzas de tracción. Material y métodos: Treinta premolares fueron tratados endodóncicamente, 10 fueron preparados para recibir una corona convencional (grupo A), 10 para endocorona (grupo B) y 10 para endocorona EPA (grupo C). Se realizaron fuerzas de tracción para obtener el valor máximo en el cual las coronas fallaron. Se realizó una prueba ANOVA para comparar los resultados. Resultados: Al someter a los tres tipos de coronas a fuerzas de tracción los resultados obtenidos fueron: 3.04 ± 0.55 MPa para la corona, 7.08 ± 1.6 MPa para la endocorona y 6.17 ± 1.12 MPa para la endocorona EPA. Conclusiones: No existió diferencia significativa entre la endocorona (7.08 MPa) y la EPA (6.17 MPa), convirtiéndose en una alternativa de tratamiento con buen pronóstico en la práctica diaria (AU)

Introduction: The alternatives of treatment of tooth with excessive wear vary not only by the restoration material but also by the economic and aesthetic value. Among the alternatives there is: conventional crown, endocrown whose main objective is the elaboration of a restorative that avoids the placement of intraconducting posts and endocrown without one axial wall (EPA) that is done when a wall; mesial, distal, vestibular or palatal is absent. Objective: To verify if the (EPA) behaves in the same way as the conventional crown and endocrown when measuring its resistance to tensile strength. Material and methods: 30 premolars were treated endodontically, ten were prepared to receive a conventional crown, 10 for endocrown and 10 for EPA. Tensile strength were performed to obtain the maximum value at which the crowns failed, an ANOVA test was performed to compare the results. Results: When the three types of crowns were subjected to tensile strength, the results obtained were; 3.04 ± 0.55 MPa for the crown, 7.08 ± 1.6 MPa for the endocrown and 6.17 ± 1.12 MPa for the EPA endocrown. Conclusions: There was no significant difference between the endocrown (7.08 MPa) and EPA endocrown (6.17 MPa) becoming an alternative treatment with good prognosis in daily practice (AU)

Comportamiento cromático de resinas acrílicas y bisacrílicas para restauraciones provisionales / Chromatic behavior of acrylic and bisacrylic resins used for provisional restorations

Introducción: Las prótesis provisionales son restauraciones usadas en prótesis fijas durante un tiempo, hasta la cementación de la prótesis definitiva. Uno de los problemas que presentan este tipo de restauraciones es el cambio de color, que afecta a la estética y, en consecuencia, produce sensación de desagrado en los pacientes. Objetivo: Evaluar, para restauraciones provisionales, con y sin el pulido final de la superficie, la estabilidad del color de dos resinas al ser sumergidas en café. Métodos: Estudio experimental in vitro, realizado en el Laboratorio de Prótesis de la Facultad de Odontología de la Universidad Nacional del Nordeste, Corrientes-Argentina, 2019. Se comparó una resina acrílica (Duralay®) con una bisacrílica (ProtempIV 3M®) para restauraciones provisionales. Se elaboraron 40 discos de resinas a partir de moldes metálicos de 25 mm de diámetro y 2 mm de espesor. Se utilizaron 20 discos para cada tipo de resina, de ellos, 10 pulidos y 10 sin pulir. Las muestras fueron almacenadas en agua destilada en estufa a 37 °C durante 24 h para hidratarlos. Luego se procedió a la toma del color. Con posterioridad, cada grupo se sumergió en café, manteniéndolos en estufa a 37 °C durante 24 h más. Seguidamente, se realizó la segunda toma del color. Se utilizó el colorímetro Kónica Minolta®, determinando la diferencia total de color ΔE. Para el análisis estadístico se utilizó ANOVA una vía y test de Tukey para identificar la diferencia entre grupos. Resultados: Se observó en el grupo de resina acrílica pulida una diferencia ΔE = 0,82 ± DS = 0,22 y de ΔE = 3,86 ± DS = 0,30 sin pulido. En el grupo de resina bisacrílica pulido se obtuvo ΔE = 4,84 ± DS = 0,25 y, para el no pulido, ΔE = 5,85 ± DS = 0,29. Conclusiones: Se comprobaron diferencias significativas en la estabilidad del color de ambas resinas. La resina bisacrílica fue la menos estable, independientemente del pulido(AU)

Introduction: Provisional prosthesis are restorations used in fixed prostheses for a while, until the definitive prosthesis is cemented. One of the problems posed by this type of restoration is the change in color, which affects esthetics and therefore creates a feeling of displeasure in patients. Objective: Evaluate, in the case of provisional restorations with and without final surface polish, the color stability of two resins when soaked in coffee. Methods: An in vitro experimental study was conducted in the Prosthesis Laboratory at the Dental School of the National University of the Northeast in Corrientes, Argentina, in the year 2019. A comparison was made of an acrylic resin (Duralay®) versus a bisacrylic resin (ProtempIV 3M®) for provisional restorations. Forty resin disks were made from metal molds 2 mm thick and 25 mm in diameter. Twenty disks were used for each type of resin, of which 10 were polished and 10 were not. The samples were stored in distilled water in a stove at 37ºC for 24 h to hydrate them. Color measurements were then taken. Next, each group was soaked in coffee and kept in the stove at 37ºC for another 24 h. A second color measurement was then taken. A Konica Minolta® colorimeter was used to determine total color difference ΔE. Statistical analysis was based on one-way ANOVA and Tukey's test was used to identify the difference between the groups. Results: In the polished acrylic resin group a difference was found of ΔE = 0.82 ± SD = 0.22, whereas in the non-polish group the difference was ΔE = 3.86 ± SD = 0.30. In the polished bisacrylic resin group the difference was ΔE = 4.84 ± SD = 0.25, whereas in the non-polish group the difference was ΔE = 5.85 ± SD = 0.29. Conclusions: Significant differences were found in the color stability of both resins. The bisacrylic resin was the least stable, regardless of polish(AU)

Eficacia del cementado indirecto / Indirect bonding efficiency

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

Resistencia adhesiva de postes de fibra a los diferentes tercios del conducto radicular / Adhesive resistance of fiber posts to different thirds of the root canal

En los últimos años resulta de elección la utilización de postes de fib ra en la rehabilitación de piezas endodónticamente tratadas. La adhesión entre poste, agente cementante y dentina radicular permitiría lograr una retención de la estructura dentro de las paredes del conducto. El objetivo de este estudio fue comparar la resistencia adhesiva en los tercios cervical, medio y apical, entre la dentina del conducto radicular y el cemento adhesivo utilizado en la cementación de postes de fibra. Se utilizaron 30 premolares inferiores uniradiculares humanos, recientemente extraídos, se realizaron los tratamientos endodónticos, se desobturaron y realizaron las preparaciones con la fresa conformadora número 3 para la cementación de postes White Post DC especial número 3 con cemento Paracore utilizando el protocolo adhesivo del mismo sistema. Las muestras fueron incluidas en acrílico cristal, cortadas en forma perpendicular al eje mayor de la pieza con una máquina de corte y por último se procedió a medir los valores de adhesión de los postes a la superficie interna de los conductos en los tres tercios con la prueba push-out mediante una máquina de ensayo universal. Los resultados arrojaron que las resistencias (media +- DE, MPa) en los tercios cervical, medio y apical, fueron 8,74 +- 3,12, 9,38 +- 2,29 y 11,11 +- 2,95, respectivamente. En el tercio apical se registró mayor resistencia. Considerando las limitaciones de esta investigación, se puede concluir que la cementación de postes de fibra con cementos resinosos, presenta mayores valores en el tercio apical y menores en el tercio cervical del conducto radicular con técnica de Push-out (AU)

Glass fiber posts: influence of cementation techniques on push-out bond strength

Aim: Glass fiber posts are indicated in the rehabilitation of extensively damaged teeth; their cementation represents a critical step in restorative dentistry. The aim of this study was to quantify and compare the push-out bond strength of glass fiber posts cemented by conventional technique, two-step technique with luting agent and two-step technique associating bulk-fill composite and luting agent. Methods: Eighty maxillary bovine incisors were endodontically treated and divided into eight groups (n = 10) according to the luting agent (Rely X ARC and Duo-link) and cementation technique (conventional technique; two-step technique with luting agent; and two-step technique associating bulk-fill composite ­ Filtek Bulk-fill flow or Surefil SDR flow ­ and luting agent). Samples were submitted to pushout bond strength test, and the fracture pattern was evaluated through scanning electron microscope. Data were submitted to two-way ANOVA and Tukey's test (α = 0.05). Results: When Rely X ARC was used, the conventional cementation technique obtained higher bond strength values than the twostep technique associated with Filtek Bulk-fill flow. When Duolink was used, the two-step technique associated with Filtek Bulk-fill flow presented higher bond strength values than the conventional technique. The most prevalent fracture patterns were adhesive between luting agent and dentin, and adhesive between bulk-fill composite and dentin. Conclusion: Two-step cementation technique associated with bulk-fill composite may be promising depending on the luting agent used

Protocolo de cementación indirecta de aparatología ortodóncica fija utilizando materiales de uso común / Indirect cementation protocol for fixed orthodontic appliances using commonly used materials

Introducción: La técnica de arco recto es una de las técnicas más utilizadas para la corrección de maloclusiones en ortodoncia; sin embargo, el éxito de la técnica radicará en la exactitud en que se posicionan los brackets. Este artículo presenta un protocolo de cementación indirecta, el cual, adicionalmente, permite una mayor accesibilidad a los materiales requeridos para este procedimiento. Objetivo: Presentar un protocolo efectivo y accesible de cementación indirecta. Material y métodos: Para este protocolo se ha utilizado materiales como resina de cementación de brackets (Transbond XT, 3M Unitek, EEUU), aislante de acrílico para separar los brackets del modelo de yeso y silicona líquida, utilizada habitualmente para autos (Kit Silicona, Johnson, Chile), para separar los brackets del soporte termoplástico, el cual fue realizado con silicona termofusible. Conclusión: El protocolo de cementación indirecta permite un buen posicionamiento de los brackets, reduciendo la posibilidad de reposicionar durante las fases de alineamiento y nivelado (AU)

Introduction: The straight arch technique is one of the most used techniques for the correction of malocclusions in orthodontics; however, the success of the technique will lie in the accuracy in which the brackets are positioned in the correct position. This article presents an indirect cementation protocol which additionally allows greater accessibility to the materials required for this procedure. Objective: Present an effective and accessible indirect cementation protocol. Material and methods: For this protocol, materials such as brace cementation resin (Transbond XT, 3M Unitek, USA), acrylic insulator have been used to separate the brackets from the gypsum and liquid silicone model, usually used for cars (Silicone Kit, Johnson, Chile), to separate the brackets from the thermoplastic support, which was made with hot melt silicone. Conclusion: The indirect cementation protocol allows a good positioning of the brackets, reducing the possibility of repositioning during the alignment and leveling phases (AU)

Restauración postendodóncica: técnica con postes accesorios de fibra de vidrio / Postendodontic restoration: a technique with accessory fiber glass posts

Utilizar esta técnica implica grandes ventajas, ya que se reduce el volumen de cemento de resina, lo que disminuye la probabilidad de contracción, formación de burbujas y vacíos internos, los cuales representanáreas de debilidad en la restauración postendodóncica. Esta técnica ya ha sido propuesta y debidamente investigada por algunos autores. Se aplica en dientes con conductos radiculares amplios que han sido debilitados por restauraciones defi cientes, desmineralización de la dentina, fi ltraciones en la corona y poste radicular o simplementeconductos amplios en pacientes de corta edad. Tenemos la firme convicciónde que no podemos garantizar la permanencia de un órgano dentalen la cavidad oral, pero sí podemos intentar prolongar su permanenciaen el alvéolo el mayor tiempo posible. La técnica que se describe en elpresente artículo consiste en colocar postes accesorios de fi bra de vidriodespués del poste principal, logrando reducir el espesor de película delagente cementante a un grado ideal.

The use of this technique, shows significant advantages, as the thicknessof the resin cement is reduced, in consequence, the contraction ratio,bubble formation, and internal voids are reduced, which represent areasof weakness in the post-endodontic restoration, this technique has beenalready proposed and properly investigated by certain authors. Thisis applied on teeth with enlarged canals, that have been weakened byineffi cient restorations, dentin demineralization, bacterial fi ltration ofcrown and post, or simply wide canals in young patients. We have afi rm conviction, that we can´t guarantee the permanence of a dentalorgan in the oral cavity, but we can try to lengthen its permanency onthe alveolus as much as possible. The technique that´s described in thisarticle, consists in placing accessory posts of fi ber glass after placingthe main post, achieving a reduction of the cement fi lm thickness toideal thicknesses.

Radiographic evaluation of cementation technique using polished, conical, triple-tapered femoral stem in hip arthroplasty / Avaliação radiográfica da técnica de cimentação com haste femoral cônica polida e tripla cunha em artroplastia do quadril

Abstract Objective To radiographically evaluate the quality of cementation and implantation technique using a polished, triple-tapered femoral stem in total hip arthroplasty (THA). Method Retrospective study with radiographic evaluation of 86 hips in 83 patients who underwent to primary THA with the triple-tapered cemented femoral stem C-Stem (DePuy Orthopedics, Warsaw, Indiana). Cases with at least one-year of follow-up were included, and data related to preoperative, immediate postoperative, and late postoperative radiographic evolution were recorded. This study analyzed, among others, the proximal femoral anatomy, the quality of cementation as described by Barrack, and the implant positioning. Cementation was also evaluated and quantified in the Gruen zones with one-year of follow-up. Results The mean age was 62.85 years. Proximal femoral anatomical conformation was Dorr type A in 34 (39.53%) cases, type B in 52 (60.46%), and no type C cases were found. Five (5.81%) cases were defined as type A by Barrack's cementation classification system, 46 (56.49%) type B, 27 (31.40%) type C, and eight (9.30%) type D. The greatest cement mantle thickness was observed in zones four (15.53 mm) and 11 (15.64 mm), and the smallest in zone nine (3.51 mm). Positioning in varus was observed in eight (9.3%) cases, valgus in 25 (29%), forward deviation in two (5%), and backward deviation in 55 (63.95%). Conclusions The C-Stem femoral system presented satisfactory results related to cementation pattern, positioning, osteolysis, and stress shielding with regard to literature referring to double-tapered or triple-tapered models, demonstrating to be a safe method, with a predictable and reliable cementing pattern.

Resumo Objetivo Avaliar radiograficamente a qualidade da técnica de cimentação e implantação de hastes femorais polidas e tripla cunha em artroplastias totais do quadril (ATQ). Método Estudo retrospectivo com avaliação de radiografias de 86 quadris em 83 pacientes submetidos à ATQ com componente femoral cimentado polido em tripla cunha C-Stem (DePuy Orthopaedics, Varsóvia, Ind.). Incluímos casos com pelo menos um ano de seguimento, foram registrados dados relacionados à evolução radiográfica pré-operatória, pós-operatória imediata e pós-operatória tardia. Avaliamos, entre outros dados, a anatomia do fêmur, a qualidade da cimentação segundo descrito por Barrack e o posicionamento da haste. A cimentação também foi avaliada e quantificada em cada zona de Gruen com um ano de seguimento. Resultados A idade média foi de 62,85 anos. A conformação do fêmur proximal foi do tipo A de Dorr em 34 (39,53%) casos, tipo B em 52 (60,46%) e não foram observados casos do tipo C. Cinco (5,81%) casos foram definidos como tipo A segundo a classificação de cimentação de Barrack, 46 (56,49%) tipo B, 27 (31,40%) tipo C e oito (9,30%) tipo D. A maior espessura média do manto foi observada nas zonas 4 (15,53 mm) e 11 (15,64 mm), a menor foi na zona 9 (3,51 mm). Foi observado posicionamento em varo em oito (9,3%) casos e em valgo em 25 (29%). Conclusão A haste femoral C-Stem apresentou resultados satisfatórios quanto ao padrão de cimentação, posicionamento, à presença de osteólise e stress shielding, tanto em relação à literatura referente aos modelos em dupla cunha quanto referente ao mesmo modelo de implante, mostrou-se um método seguro e com padrão de cimentação previsível e confiável.

Tensile Strength of Resin Cements Used with Base Metals in a Simulating Passive Cementation Technique for Implant-Supported Prostheses

Abstract The aim of this study was to analyze the tensile strength of two different resin cements used in passive cementation technique for implant-supported prosthesis. Ninety-six plastic cylinders were waxed in standardized forms, cast in commercially pure titanium, nickel-chromium and nickel-chromium-titanium alloys. Specimens were cemented on titanium cylinders using self-adhesive resin cement or conventional dual-cured resin cement. Specimens were divided in 12 groups (n=8) in accordance to metal, cement and ageing process. Specimens were immersed in distilled water at 37 °C for 24 h and half of them was thermocycled for 5,000 cycles. Specimens were submitted to bond strength test in a universal test machine EMIC-DL2000 at 5 mm/min speed. Statistical analysis evidenced higher tensile strength for self-adhesive resin cement than conventional dual-cured resin cement, whatever the used metal. Self-adhesive resin cement presented higher tensile strength compared to conventional dual-cured resin cement. In conclusion, metal type and ageing process did not influence the tensile strength results.

Resumo O objetivo deste estudo foi analisar a resistência à tração de dois diferentes cimentos resinosos usados na técnica de cimentação passiva de próteses implanto-suportadas. Noventa e seis cilindros plásticos foram encerados em formas padronizadas, fundidos em titânio grau 2 comercialmente puro e ligas de níquel-cromo e níquel-cromo-titânio. Amostras foram cimentadas sobre cilindros de titânio usando um cimento auto-adesivo ou um cimento convencional de dupla polimerização. Os espécimes foram divididos em 12 grupos (n=8) de acordo com o metal, cimento e processo de envelhecimento. Espécimes foram imersos em água destilada a 37 °C por 24 h e metade deles foi termociclado por 5,000 ciclos. Espécimes foram submetidos ao ensaio de tração numa máquina universal de ensaios (velocidade de 5 mm/min). Análise estatística evidenciou maior resistência à tração do cimento auto adesivo do que o cimento convencional de dupla polimerização, independente do metal utilizado. O cimento resinoso auto adesivo apresentou maior resistência à tração do que o cimento convencional de dupla polimerização. O tipo de metal e o processo de envelhecimento não tiveram influência nos resultados.

Effects of the application techniques of self-adhesive resin cements on the interfacial integrity and bond strength of fiber posts to dentin

ABSTRACT Objective: To evaluate the influence of an application technique of a glass-fiber post using self-adhesive resin cements on the push-out bond strength and the presence of bubbles in the root thirds. The cements were either applied according to the manufacturer's instruction or using a commercial delivering system (Centrix), at which the cement pastes were collected and applied after manipulation. Material and Methods: Self-adhesive resin cements (RelyX U200/3M ESPE-U200; Maxcem Elite/Kerr-MAX; Clearfil SA Cement/Kuraray-CSA) and a conventional cement (RelyX ARC/3M ESPE-ARC) were used to cement a post and applied either based on the manufacturer's instructions or using a Centrix syringe to deliver the cements directly onto the post of choice, or directly into canal. The roots were scanned with a micro-computed tomography (μCT) and then sectioned into nine 1-mm thick slices for a push-out bond strength test. The μCT images showed the percentage of bubbles in the root thirds (cervical, medium, and apical). Data were analyzed with three-way ANOVA/Tukey (α=0.05). Results: Triple interaction was not significant (p>0.05). The interaction “material” vs “root third” was not significant. A significant interaction was observed between “material” vs “application technique” (p<0.05). For ARC, U200, and MAX, significantly lower percentages of bubbles were observed when the Centrix syringe delivered the cements. Equivalent percentages of voids were observed for CSA, irrespective of the application technique (p>0.05). Significantly higher bond strength was observed when the self-adhesive resin cements were applied using the Centrix delivery system, in comparison with the manufacturer's instructions (p<0.05). Bond strength varied with the root third: cervical>medium>apical (p<0.05). No correlations were found between the bond strength and voids. Conclusions: Bond strength and voids are negatively influenced by the conventional application technique for luting fiber posts. The delivery system (Centrix) seems to produce better results when cementing fiber posts.

Evaluación del grado de filtración s nivel de los conductos laterales y su relación con el material de obturación, luego de la instalación de anclajes intrarradiculares / Evaluation of the degree of leakage in lateral canals and its relationship with the filling material after luting intraradicular posts

Objetivo: Evaluar el grado de filtración en conductos laterales simulados y su relación con el material de obturación, luego de la instalación de anclajes intrarradiculares. Materiales y métodos: se usaron 30 premolares humanos cuyos conductos radiculares se instrumentaron con ProTaper Universal (Denstply Maillefer, Ballaigues, Suiza) hasta F3 y se dividieron aleatoriamente en tres grupos. Grupo 1: cionducto lateral obturado con el medio de cementado de resina SmartCem 2 (Dentsply Detrey, Konstanz, Alemania). Los conductos radiculares fueron obturados con un cono de gutapercha F3, conos accesorios y termocompactados con Guttacondensor #45 (Dentsply Maillefer, Ballaigues, Suiza). Como sellador se empleó AH26 (Dentsply Detrey, Konstanz, Alemania). A continuación se realizó la preparación para poste con fresas de Largo (Densply) #1, 2 y 3 y taladros preparadores del poste por emplear. Se talló un conducto lateral simulado por mesial de cada muestra, a 6 mm del borde coronario. Se cementaron, en cada conducto, postes orgánicos de fibra de vidrio cilíndricos Glass Post (Densell/GDK, Buenos Aires, Argentina) con cemento de resina SmartCem 2, introducido a la preparación intrarradicular con un lentulo (Detsply) a baja velocidad. La resina se fotopolimerizó a través del poste durante sesenta segundos con una lámpara halógena Ultralux EL (Dabi Atlante, Riberao Preto, San Pablo, Brasil). En estas condiciones, el conducto lateral simulado quedaba obturado con la resina cementante. Grupo 2: conducto lateral obturado con el material de obturación endodóntico. Se procedió de igual forma que en el Grupo 1, sólo que el tallado del conducto lateral simulado se realizó antes de la obturación endodóntica, de modo que éste estuviese obturado con alguno de los materiales de obturación empleados . Grupo 3: conducto lateral vacío. Se procedió como en el grupo 1, sólo que el tallado del conducto lateral simulado se realizó después del cementado de los postes de fibra de vidrio.

Reemplazo total de cadera hibrido con tallos pulidos y conicos, tecnica de cementado moderna y superficie ceramica-ceramica: Analisis de las complicaciones / Total hip replacement with hybrid polished tapered stems, modern cementing technique and ceramic-ceramic surface. Analysis of complications

Introducción: Se han logrado excelentes resultados con los tallos pulidos, cementados con tecnicas modernas, aun en pacientes jovenes, aunque su combinacion con superficie ceramica solo se ha comunicado en forma aislada. El objetivo de este estudio es analizar los resultados y las complicaciones de una serie de artroplastias de cadera con superficie ceramicaceramica, y tallos pulidos y conicos cementados con tecnicas de segunda y tercera generacion. Materiales y Métodos: Se evaluaron los resultados, las complicaciones relacionadas con el par de friccion y la supervivencia de 277 pacientes tratados con artroplastias de cadera con tallos pulidos y conicos cementados, en forma moderna, asociados a un par de friccion ceramica-ceramica. La edad promedio fue 56 anos; y el seguimiento minimo, de 6 anos. Resultados: No se detectaron aflojamientos radiologicos, migraciones, ni radiolucencias. La incidencia de infeccion fue del 1,3%. La incidencia de complicaciones por causas atribuibles a la cupla ceramica fue del 4%, y la de revision, del 1,4%. La supervivencia a siete anos, considerando revision por cualquier motivo fue del 95,8% (IC95% 94-99%), y considerando el aflojamiento aseptico, del 100%. Todos los casos de luxacion produjeron impregnacion metalica de la cabeza ceramica y esta fue la causa mas frecuente de revision. La incidencia de sonidos ha sido excepcionalmente baja comparada con las de otras series con fijacion no cementada. Conclusión: La asociacion de cementado moderno y tallos pulidos y conicos con superficies ceramicas ha demostrado ser una alternativa atractiva con una supervivencia a siete anos del 95%, sin aflojamientos asepticos. Nivel de Evidencia: IV

Introduction: Polished cemented stems with modern cementing techniques have shown excellent results even in young patients; nevertheless their results in combination with ceramic bearings are not known due to the lack of reports. We analyzed the results and complications of hip hybrid arthroplasties combining second- and third-generation cemented polished tapered stems and ceramic-ceramic bearings. Methods: Results, complications related to ceramic surfaces and survival rate of 277 patients treated with hip arthroplasties with polished stems cemented with modern techniques were evaluated. The mean age was 56 years and the minimum follow-up was 6 years. Results: No radiographic loosening, migration or radiolucencies were detected. The infection rate was 1.3%. The complication rate due to ceramic bearing was 4%, revision was required in 1.4%. Seven-year survival with revision for any reason as the endpoint was 95.8% (95%CI, 94-99%) whereas it reached 100% for aseptic loosening. Dislocation with metal impregnation was responsible of almost all revisions caused from complications related to bearing surfaces. The incidence of squeaking has been exceptionally low compared to other series with cementless fixation. Conclusion: The combination of modern cementing techniques of polished stems with ceramic on ceramic bearings has proven to be an attractive alternative with a 7-year survival of 95%, and no aseptic loosening. Level of Evidence: IV

Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography

ABSTRACT Objective The purpose of the study was to use the photonic imaging modality of optical coherence tomography (OCT) to compare the marginal adaptation of composite inlays fabricated by direct and indirect techniques. Material and Methods Class II cavities were prepared on 34 extracted human molar teeth. The cavities were randomly divided into two groups according to the inlay fabrication technique. The first group was directly restored on cavities with a composite (Esthet X HD, Dentsply, Germany) after isolating. The second group was indirectly restored with the same composite material. Marginal adaptations were scanned before cementation with an invisible infrared light beam of OCT (Thorlabs), allowing measurement in 200 µm intervals. Restorations were cemented with a self-adhesive cement resin (SmartCem2, Dentsply), and then marginal adaptations were again measured with OCT. Mean values were statistically compared by using independent-samples t-test and paired samples t-test (p<0.05), before and after cementation. Results Direct inlays presented statistically smaller marginal discrepancy values than indirect inlays, before (p=0.00001442) and after (p=0.00001466) cementation. Marginal discrepancy values were increased for all restorations after cementation (p=0.00008839, p=0.000000952 for direct and indirect inlays, respectively). The mean marginal discrepancy value of the direct group increased from 56.88±20.04 µm to 91.88±31.7 µm, whereas the indirect group increased from 107.54±35.63 µm to 170.29±54.83 µm. Different techniques are available to detect marginal adaptation of restorations, but the OCT system can give quantitative information about resin cement thickness and its interaction between tooth and restoration in a nondestructive manner. Conclusions Direct inlays presented smaller marginal discrepancy than indirect inlays. The marginal discrepancy values were increased for all restorations that refer to cement thickness after cementation.

Fijación simplificada de pernos de fibra con cementos de resina autograbante y de ionómero de vidrio modificado con resina: reporte de caso y revisión de la literatura / Simplified placement of fiber posts with self-etching resin cements and resin-modified glass ionomer cement: report of a case and review of the literature

Los pernos de fibra pueden ser fijados con técnicas simplificadas empleando cementos de ionómero de vidrio modificados con resina o de resina autograbante. De esta manera se evitan las técnicas de adhesión y sus variables complejas que comprometen muchas veces el resultado final del tratamiento.Los resultados son promisorios en cuanto a valores de retención, simplificación de la técnica y agilidaddel proceso clínico. En el artículo, se presenta un caso clínico de fijaciónsimplificada de un perno de fibra con un cemento de resina autograbante y se revisa la literatura científica...

Does MTA affect fiber post retention in repaired cervical root canal perforations?

Abstract This study evaluated the effect of mineral trioxide aggregate (MTA) on the retention of fiber posts in repaired root canal perforations. Ten-millimeter post spaces were prepared in 60 endodontically treated bovine incisors. Root perforations were created in half of the root canals in the cervical area prior to being filled with white MTA-Angelus. Fiber posts were luted into the root canals with two self-adhesive (RelyX Unicem or Set) or self-etching (Panavia F) resin cements. The posts were submitted to a pull-out test, and the data were submitted to two-way ANOVA and Tukey's post hoc tests (α = 0.05). The fiber posts exhibited reduced retention in MTA-repaired root canal perforations, regardless of the type of resin cement that was used (p < 0.001). Self-adhesive resin cements provided higher bond strength values than Panavia F, while no difference was observed between RelyX Unicem and Set (p > 0.05). The presence of MTA in repaired root perforations negatively affected post retention. In addition, self-adhesive cements seemed to be the best option to lute fiber posts within a root canal in these cases.

Influência na resistência de união de pinos de fibra de vidro com e sem retenções mecânicas em função dos materiais utilizados para cimentação: teste de 'push-out' / Influence on the bond strength of glass fiber posts with and without mechanical retentions depending of materials used for cementing: push-out test

Este estudo teve como objetivo avaliar a influência na resistência de união de pinos de fibra de vidro (PFV) com retenções mecânicas (CRM) e sem retenções (SR), associados a três materiais: RelyX ARC cimento resinoso convencional dual com sistema adesivo Adper Single Bond (ASB), convencional de 2 passos; RelyX U200 cimento resinoso auto condicionante dual e resina flow SDR foto ativada, com sistema adesivo Prime & Bond 2.1 (PB), convencional de 2 passos; nos terços cervical (C), médio (M) e apical (A), por meio do teste de push-out. Sessenta incisivos bovinos foram selecionados, tiveram as coroas seccionadas para padronizar 17mm de raiz e foram submetidas ao tratamento endodôntico, para posterior cimentação do PFV. Foram divididas aleatoriamente em 2 grupos (N=30), quanto ao tipo de PFV: CRM - com retenções mecânicas (Glassix+plus no2) e SR - sem retenções (Exacto no2). Todos os PFV apresentavam formato cônico. Cada grupo foi subdividido em 3 (N=10), quanto ao tipo de material: cimento RelyX ARC+ASB; cimento RelyX U200 (auto condicionante) e resina SDR+PB. Todas as orientações dos fabricantes para tempo de manipulação e foto ativação do material foram rigorosamente respeitadas. As raízes foram mantidas em saliva artificial e decorridas 24h da cimentação dos PFV, foram seccionadas perpendicularmente ao longo eixo, obtendo 9 fatias de aproximadamente 1mm, cuja identificação foi feita de acordo com o terço correspondente. O teste de push-out foi realizado em máquina de ensaio universal com célula de carga de 50N; velocidade de 0,5mm/min, da direção apical para a cervical da fatia até que o pino fosse deslocado, respeitando o formato cônico do canal radicular. Todos os espécimes foram analisados em microscopia óptica, aumento de 200 vezes, quanto aos tipos de falha ocorrido. Os dados foram tabulados considerando as variáveis dos diferentes materiais utilizados para a cimentação, presença ou não de retenções mecânicas nos PFV e terços radiculares. Os valores de resistência de união (Ru) obtidos foram submetidos ao teste de normalidade Kolmogorov- Smirnov, à análise de variância a três critérios (ANOVA) e ao teste LSD de Fisher (p<0,05). Os resultados mostraram diferença estatisticamente significante nos terços C, M e A, respectivamente para os cimentos ARC com pino Glassix+plus, média e desvio padrão (MPa) a seguir, 8,50 (4,76); 6,99 (3,55); 4,71 (2,13) e U200 com pino Exacto: 9,40 (4,93); 8,02 (4,67); 4,67 (1,86); a resina SDR não interagiu significativamente com os PFV CRM 6,78 (2,72); 5,97 (2,45); 2,67 (1,55) e SR 7,24 (3,55); 6,86 (2,84); 4,10 (1,90). A análise microscópica mostrou predominância de falhas adesivas entre cimento e dentina e mista para todos os grupos. O cimento U200 com pino Exacto apresentou o melhor desempenho, seguido do ARC com pino Glassix+plus. A resina SDR teve desempenho semelhante para ambos os PFV. Todos os grupos apresentaram valores de Ru maiores no terço cervical, intermediários no terço médio e menores no terço apical.(AU)

This study aimed to evaluate the influence on the bond strength of glass fiber posts (GFP) with mechanical retention (WMR) and without retentions (NR), associated with three materials: RelyX ARC total-etching resin cement dual cure with Adper Single Bond (ASB) adhesive system, conventional 2 steps; RelyX U200 self-etching resin cement dual cure, and flowable resin SDR, activated by light, with Prime & Bond 2.1 adhesive system conventional 2 steps in the cervical (C), medium (M) and apical (A) thirds by the "push-out" test. Were selected sixty bovine incisors, had the crowns sectioned to root was standardized 17mm, were submitted to endodontic treatment, for cementing the GFP later. Were randomly divided into 2 groups (N=30), according to the GFP: WMR - with mechanical retentions (Glassix+plus ≠2) and NR - without retentions (Exacto ≠2). All GFP had conic shape. Each group was divided into 3 (N=10), according to material: RelyX ARC+ASB, RelyX U200 (self-etching) and flowable resin SDR+PB. All guidelines of manufacturers to handling time and cure time of the material were strictly adhered. The roots were kept in artificial saliva and 24 hours after GFP cementing it were sectioned perpendicular to the long axis, obtaining nine slices of approximately 1mm, which identification was done according to the corresponding third. The "push-out" test was performed with a universal test machine, 50N load cell; crosshead speed of 0.5 mm/min, the load was applied in an apical to cervical direction until the post dislodged from the specimen, respecting the conical shape of the root canal. Subsequently, all specimens were analyzed with optical microscopy 200 times increase to evaluate failure modes. Data were tabulated considering the materials used for cementing, presence or absence of mechanical retentions in GFP and root thirds. The bond strength values (BS) were submitted to Kolmogorov-Smirnov normality test, three-way ANOVA and Fisher's LSD test (p<0.05). The values showed statistically significant differences in thirds C, M and A, respectively for the ARC with Glassix+plus, average and standard deviation (MPa): 8.50 (4.76); 6.99 (3.55); 4.71 (2.13) and U200 with Exact post: 9.40 (4.93); 8.02 (4.67); 4.67 (1.86). SDR resin does not significantly interacted with GFP WMR 6.78 (2.72); 5.97 (2.45); 2.67 (1.55) and NR 7.24 (3.55); 6.86 (2.84); 4.10 (1.90). The microscopic analysis showed predominance of failure between cement and dentine and mixed for all groups. U200 cement with Exacto post had the best performance, followed by ARC with Glassix+plus post, SDR resin has similar performance for both GFP. All groups showed BS values higher in the cervical third, intermediate in the middle third and smaller in the apical third.(AU)