Effect of several repair techniques on the bond strength between composite resin and degraded Y-TZP ceramic / Efeito de várias técnicas de reparo na resistência de união entre resina composta e zircônia degradada

Objective: To evaluate the bond strength of different repair treatments for composite resin to aged Y-TZP ceramics. Material and Methods: Zirconia blocks were cut into smaller specimens, sintered according to manufacturer's recommendations (final dimensions of 4×4×3 mm), and randomly allocated into nine groups (n=15) according to the surface treatment and presence/ absence of aging of the substrate (subjected to lowtemperature degradation - LTD), as follows: without LTD (Control: without treatment; TBS: tribochemical silica coating + silane + adhesive); with LTD (Control-LTD: without treatment; TBS-LTD: TBS with hydrothermal degradation; MoS-LTD: Monobond S + adhesive; MoPLTD: Monobond Plus + adhesive; MZP-LTD: Metal/ Zirconia Primer + adhesive; USB-LTD: Single Bond Universal; AP-LTD: Alloy primer + adhesive). LTD was simulated in an autoclave (134 °C, 2 bar, 5 h). The ceramic blocks were embedded in PVC cylinders with a self-curing acrylic resin; each surface treatment protocol was performed; a composite resin cylinder ( : 3.25 mm and height: 3 mm) was then build-up using split metallic matrices. All the specimens were aged (thermocycling + storage in water for 90 days) and subjected to the shear bond strength test using a universal testing machine (1 mm/min). The failure mode was classified into four types: adhesive, composite resin cohesive fracture, ceramic cohesive fracture, and mixed. The bond strength values were subjected to Mann­Whitney test. Results: Only air-abraded samples (TBS and TBS­LTD) survived thermocycling. More than 80% of the samples of the other groups presented pre-test failures. TBS groups presented higher values of bond strength (3.94) compared to TBSLTD (0.96). The predominant type of failure for the surviving samples were adhesive. Conclusion: Air particle abrasion is mandatory to improve the bond strength of the Y-TZP substrate; an aged substrate presents an even more unfavorable scenario for adhesion. (AU)

Objetivo: Avaliar a resistência de união ao cisalhamento gerada por diferentes técnicas de reparo em resina composta aderida em zircônia envelhecida (sujeita a degradação a baixa temperatura - LTD). Material e Métodos: blocos de zircônia foram seccionados em espécimes, sinterizados de acordo com o fabricante (dimensões finais de 4x4x3 mm), e aleatorizados em nove grupos (n=15) de acordo com o tratamento de superfície e presença/ausência de envelhecimento do substrato (LTD), conforme: sem LTD (Control: sem tratamento; TBS: tribosilicatização + silano + adesivo); com LTD (Control-LTD: Monobond S + adesivo; MoP-LTD: Monobond plus + adesivo; MZPLTD: Meta/Zirconia primer + adesivo). LTD foi simulada em autoclave (134 °C, 2 bar, 5 h). Os blocos de cerâmica foram embutidos em cilindros de PVC com resina acrílica autopolimerizável; cada tratamento de superfície foi realizado; um cilindro de resina composta ( : 3,25 mm 3 mm de altura) foi confeccionado usando matrizes metálicas bipartidas. Todos os espécimes foram envelhecidos (termociclagem + armazenagem em água por 90 dias) e sujeitos ao teste de cisalhamento usando um equipamento de teste universal (1 mm/ min). O modo de falha foi classificado em quatro grupos: adesivo, fratura coesiva em resina composta, fratura coesiva da cerâmica, e mista. Os valores de adesão foram sujeitos ao teste de Mann-Whitney. Resultados: somente as amostras jateadas (TBS e TBSLTD) sobreviveram a termociclagem. Mais que 80% dos espécimes dos outros grupos apresentaram falhas préteste. Os grupos TBS apresentaram os maiores valores de resistência ao cisalhamento (3,94) comparado com TBS-LTD (0,96). Os tipos predominantes de falha para os espécimes sobreviventes foi adesiva. Conclusão: o jateamento é recomendável para aumentar a resistência adesiva à zircônia; um substrato envelhecido apresenta um cenário mais desfavorável de adesão. (AU)

Mantenimiento, manejo y cuidado de las prótesis dentales en pacientes atendidos en una consulta de estomatología general integra / Preservation, handling and care of the dental prosthesis in patients assisted in a comprehensive general stomatology service

Se realizó un estudio descriptivo y transversal de los 110 pacientes portadores de prótesis dentales, atendidos en la consulta de Estomatología General Integral de la Clínica Estomatológica Provincial Docente "Mártires del Moncada" de Santiago de Cuba, en el período de septiembre a diciembre del 2015, con el propósito de identificar el mantenimiento, los cuidados y manejos en los aparatos protésicos. Se obtuvo un predominio de los pacientes que portaban prótesis total superior (50,0 %), de los que las habían usado por más de 5 años (52,7 %) y de las prótesis en mal estado (58,2 %); la higiene bucal deficiente resultó más frecuente en el sexo masculino (67,7 %) al aplicar el índice de Love.

A descriptive and cross-sectional study of the 110 patients with dental prosthesis assisted in the General comprehensive stomatology service of "Mártires del Moncada" Teaching Provincial Stomatological Clinic in Santiago de Cuba, was carried out from September to December, 2015, aimed at identifying the preservation, caring and handling in the prosthetic appliances. There was a prevalence of the patients that carried upper total prosthesis (50.0%), of those that had used them for more than 5 years (52.7%) and of the prosthesis in poor conditions (58.2%); poor oral hygiene was more frequent in the male sex (67.7%) when implementing the Love index.

Reparación intraoral de una prótesis parcial fija metal-cerámica de seis unidades con resina compuesta: relato del caso / Repair of a six-unit fixed partial denture metal-ceramics with composite resin: case report

Múltiples son los factores que pueden desencadenar fracturas de porcelana en una prótesis parcial fija metal-cerámica, aunque esta situación no siempre determina un reemplazo. La reparación de porcelana mediante el uso de resina compuesta es una alternativa con ventajas de una fácil manipulación y bajo costo. El objetivo del presente artículo es presentar a la resina compuesta como una opción con resultados considerables en la reparación de prótesis metal-cerámicas fracturadas, con alto compromiso estético. Se presenta un caso clínico de reparación intraoral de una prótesis fija metal-cerámica de seis unidades en el sector anterior superior. El tratamiento realizado incluyó fresado de la superficie de porcelana, aislamiento absoluto, grabado ácido con fluoruro de fosfato acidulado, microarenado con óxido de aluminio, silanización, aplicación del adhesivo convencional y tres tipos de resinas compuestas, resina opaca, microhíbrida y resina de nanorelleno. A los 8 meses se evaluó la adaptación de la reparación mediante un explorador e inspección visual, secando con una jeringa triple donde no se observó signos de percolación alguna. Basado en los resultados se puede considerar a esta combinación de resinas compuestas como una alternativa útil en la reparación de porcelana fracturada.

There are multiple factors that can trigger a fracture of porcelain in a metal-ceramic fixed partial denture, although a replacement is not always required. The porcelain repair using composite resin is an alternative with advantages such as easy handling and low cost. The aim of this paper is to present the composite as an option with significant results in the repair of fractured metal-ceramic prostheses, with a high aesthetic commitment. We report a case of intraoral repair of a six-unit metal-ceramic fixed prosthesis in the anterior superior sector. The treatment provided included milling of the surface of porcelain, absolute isolation, acid etching with acidulated phosphate fluoride, aluminium oxide sandblasting, silanization, conventional adhesive application and three types of composite resins: opaque resin, micro-hybrid resin and nanofilled resin. After 8 months we assessed the adaptation of the repair using a surface explorer and visual inspection, drying with a triple syringe. No signs of seepage were observed. Based on the results, this combination of composite resins can be considered as a useful alternative in the repair of broken porcelain.

Avaliação da resistência ao cisalhamento e da durabilidade de união entre sistemas para reparo em metalocerâmicas e titânio / Evaluation of shear bond strength and bond durability of metal-ceramic repair systems and titanium

O reparo de restaurações metalocerâmicas fraturadas é uma opção de tratamento que possibilita o aumento da longevidade da restauração, preservando a estrutura dental, além de ser uma alternativa rápida e de menor custo. Entretanto, o estabelecimento de uma união forte e estável entre material reparador e substrato da restauração fraturada é essencial para o sucesso do reparo. Levando-se em consideração a grande utilidade dos reparos quando corretamente indicados e a possibilidade de um aprimoramento dos mesmos com esses novos sistemas, conforme prometem os fabricantes, foi propósito deste estudo avaliar, em titânio comercialmente puro, a resistência ao cisalhamento de quatro sistemas comerciais de reparo para metalocerâmicas e da variação de um destes, bem como a durabilidade de união após armazenamento em água. Foram confeccionados discos (9 × 3 mm) em titânio comercialmente puro. Estes foram incluídos em anel de PVC com resina acrílica e suas superfícies regularizadas com lixas de carbeto de silício de diferentes granulações (120, 220 e 320) em politriz. Os espécimes receberam um dos seguintes tratamentos (n=10): 1) Epricord, 2) Bistite II DC, 3) Cojet, 4) Scotchbond Multi Uso Plus (grupo Controle), e 5) uma variação do grupo Controle, na qual foram empregadas partículas de sílica do sistema Cojet Sand em substituição às de óxido de alumínio. Os espécimes foram armazenados em água destilada a 37ºC por 24 horas, termociclados (5.000 ciclos - 5º e 55ºC) e, então, armazenados nas mesmas condições descritas anteriormente, por um período adicional de 24 horas ou 6 meses. O ensaio de cisalhamento foi realizado em máquina de ensaios Material Test System 810 com velocidade de 0,5 mm/minuto. O modo da fratura foi avaliado em lupa estereoscópica (30x). Às 24 horas, as médias de resistência (MPa) dos grupos de 1 a 5 foram respectivamente: 13,00 + 2,04c, 8,10 + 1,16d, 18,34 + 2,16b, 13,41 + 1,42c, e 22,73 + 1,42a . Aos 6 meses, foram: 11,20 + 1,26b , 4,79 + 0,38c , 7,36 + 1,91a, 10,11 + 1,29b, e 18,55 + 1,22a . O armazenamento em água afetou significativamente a resistência de união dos grupos 2, 4 e 5, reduzindo suas resistências. Às 24 horas, a resistência ao cisalhamento da combinação Scotchbond Multi Uso/Cojet Sand foi significativamente maior em relação aos demais grupos. Aos 6 meses, o sistema Cojet e a combinação Cojet Sand/ Scotchbond Multi Uso Plus foram estatisticamente superiores aos demais grupos e iguais entre si

Repair is a good alternative treatment that can increase clinical longevity of the failed restoration, preserving tooth structure, with the advantages of less chair time and lower cost. However, the clinical success of repair depends on establishing a strong and longterm durable bond between the repair material and the metal surface of the failed restoration. Considering the great benefit of intra-oral repairs and the possibility of improvement with the use of new available repair systems, the purpose of the present study was to evaluate shear bond strength of different repair systems to commercially pure titanium (CP Ti) and bond durability after long-term water storage. One-hundred disk specimens of cast CP Ti (9 × 3 mm) were embedded in a PVC ring and their bonding surfaces were smoothed with silicon carbide papers (120, 220, and 320 grit) using a polisher. Specimens were divided into 5 groups of 20, which received one of the following repair systems: 1) Epricord, 2) Bistite II DC 3) Cojet, 4) Scotchbond Multipurpose Plus (control Group), and 5) Cojet Sand plus Scotchbond Multipurpose Plus (variation of the control Group). The specimens were stored in distilled water for 24 hours at 37ºC, thermal cycled (5,000 cycles ­ 5º to 55ºC) and then stored in distilled water at 37o C for either 24 hours or 6 months. Shear bond tests were performed in a mechanical testing machine with a crosshead speed of 0.5 mm/minute. Each specimen was examined under a stereoscopic lens with ×30 magnification. At 24 hours, the mean values (MPa) for the groups 1 to 5 were respectively 13,00 + 2,04c , 8,10 + 1,16d, 18,34 +2,16b, 13,41 + 1,42c, e 22,73 + 1,42a. After 6 months, the mean (MPa) of each group was respectively 11,20 + 1,26b , 4,79 + 0,38c, 17,36 + 1,91a , 10,11 + 1,29b e 18,55 + 1,22a. Long-term water storage significantly affected groups 2, 4, 5, which showed a significant decrease of shear bond strength. At 24 hours, Cojet Sand/Scotchbond Multipurpose Plus showed the highest shear bond strength when compared to the other four groups. After 6 months, Cojet Sand/Scotchbond Multipurpose Plus and Cojet systems were not statistically different and were statistically superior to the other groups

Reparación intraoral de restauración cerámica: reporte de caso / Intraoral repair of fractured ceramic restorations: a case report

Las cerámicas dentales han logrado en estos tiempos imitar de manera excelente las propiedades ópticas y colorimétricas que tiene la dentición natural, y hoy por hoy en sus características y manipulación se concentran los intentos por lograr la perfección de la estética dental indirecta. Lamentablemente, estas no están exentas de riesgo a sufrir un accidente que las dañe o fracture,sobre todo si son en el sector anterior y, si no es posible hacer el recambio de la pieza protésica por alguna razón, se requeriría una solución urgente y necesariamente lo más compatible con la estética lograda, inclusive en aquella trabajada con subestructurasde metal.

Dental ceramics have achieved great way to mimic the optical and colorimetric properties having natural teeth, and today in its handling characteristics and focus efforts to achieve the perfection of the cosmetic dentistry indirectly. Unfortunately, these are not without risk to suffer an accident that damaged or fracture, especially if they are in the front and if you can not make the prosthetic replacement part for any reason, would require an urgent solution necessarily most compatible with the aesthetics accomplished, including those working with metalic substructures.

Influence of surface treatment and cyclic loading on the durability of repaired all-ceramic crowns

OBJECTIVE: This study investigated the durability of repaired all-ceramic crowns after cyclic loading. MATERIAL AND METHODS: Eighty In-ceram zirconia crowns were fabricated to restore prepared maxillary premolars. Resin cement was used for cementation of crowns. Palatal cusps were removed to simulate fracture of veneering porcelain and divided into 4 groups (n = 20). Fracture site was treated before repair as follows: roughening with diamond bur, (DB); air abrasion using 50 µm Al2O3, (AA) and silica coating using Cojet system followed by silane application, (SC). Control group (CG) 20 specimens were left without fracture. Palatal cusps were repaired using composite resin. Specimens were stored in water bath at 37ºC for one week. Ten specimens of each group were subjected to cyclic loading. Fracture load (N) was recorded for each specimen using a universal testing machine. Two-way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) test (a=.05) were used for statistical analysis. RESULTS: There was statistically significant difference between control and tested groups, (p<0.001). Post Hoc analysis with the Tukey HSD test showed that cyclic loading fatigue significantly decreased means fracture load of control and test groups as follows (CG, 950.4±62.6 / 872.3±87.4, P = 0.0004), (DB, 624.2 ±38 / 425.5± 31.7, P <.001), (AA, 711.5 ±15.5 / 490 ± 25.2, p <0.001) and (SC, 788.7 ± 18.1 / 610.2 ± 25.2, P <.001), while silica coating and silane application significantly increased fracture load of repaired crowns (p<0.05). CONCLUSION: Repair of fractured In-ceram zirconia crowns after chairside treatment of the fracture site by silica coating and silane application could improve longevity of repaired In-ceram zirconia crowns.

Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations

The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11) were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05). The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.

Microtensile bond strength of a repair composite to leucite-reinforced feldspathic ceramic

The purpose of this study was to evaluate the microtensile bond strength of a repair composite resin to a leucite-reinforced feldspathic ceramic (Omega 900, VITA) submitted to two surface conditionings methods: 1) etching with hydrofluoric acid + silane application or 2) tribochemical silica coating. The null hypothesis is that both surface treatments can generate similar bond strengths. Ten ceramic blocks (6x6x6 mm) were fabricated and randomly assigned to 2 groups (n=5), according to the conditioning method: G1- 10 percent hydrofluoric acid application for 2 min plus rinsing and drying, followed by silane application for 30 s; G2- airborne particle abrasion with 30 µm silica oxide particles (CoJet-Sand) for 20 s using a chairside air-abrasion device (CoJet System), followed by silane application for 5 min. Single Bond adhesive system was applied to the surfaces and light cured (40 s). Z-250 composite resin was placed incrementally on the treated ceramic surface to build a 6x6x6 mm block. Bar specimens with an adhesive area of approximately 1 ± 0.1 mm² were obtained from the composite-ceramic blocks (6 per block and 30 per group) for microtensile testing. No statistically significant difference was observed between G1 (10.19 ± 3.1 MPa) and G2 (10.17 ± 3.1 MPa) (p=0.982) (Student's t test; á = 0.05). The null hypothesis was, therefore, accepted. In conclusion, both surface conditioning methods provided similar microtensile bond strengths between the repair composite resin and the ceramic. Further studies using long-term aging procedures should be conducted.

A proposta desse estudo foi avaliar a resistência à microtração entre uma resina composta e uma cerâmica feldspática submetida a diferentes tratamentos de superfície. A hipótese foi que os tratamentos de superfície (deposição de sílica + silanização e o ácido fluorídrico + silanização) promovessem resistências adesivas semelhantes. Dez blocos cerâmicos (Omega 900) de 6x6x6mm foram confeccionados e divididos em dois grupos: G1 - ácido fluorídrico 10 por cento/2 min + silanização; G2 Sistema CoJet: jateamento com partículas de sílica de 30 µm (CoJet-Sand) + ESPE-Sil. Em seguida, o adesivo Single Bond foi aplicado na superfície e fotopolimerizado (40 s); a resina composta Z-250 foi condensada, obtendo-se um bloco de 6 mm. Depois da armazenagem (água destilada/37ºC/7 dias), espécimes retangulares foram seccionados com disco diamantado (6 corpos-de-prova por bloco e 30 corpos-de-prova por grupo), com 1 ± 0,1 mm² de área adesiva. Cada corpo-de-prova foi fixado a um dispositivo adaptado com cianoacrilato e o teste de tração foi realizado. Os dados foram submetidos ao Teste t de Student (p>0,05). A hipótese nula foi aceita (p=0.982): G1 (10,19 ± 3,1 MPa) e G2 (10,17 ± 3,1 MPa) foram similares estatisticamente. Concluiu-se que os métodos de condicionamento da superfície cerâmica geram resistência adesiva similar à da cerâmica. Estudos posteriores empregando envelhecimento a longo prazo devem ser realizados.

O uso de microondas para polimerização de prótese total implanto-suportada submetida à carga imediata / Use of microwave for polymerization of implant-supported total prostheses submitted to the immediate load

O presente trabalho demonstra a utilização do forno de microondas para polimerização de prótese total implanto-suportada submetida à carga imediata, reduzindo o período entre a instalação dos implantes e da prótese, com resultados bastante satisfatórios e maior comodidade para o paciente.

Evaluation of shear bond strength of composite to porcelain according to surface treatment

This study evaluated the shear bond strength of porcelain/composite using 40 metal + porcelain + composite cylindrical specimens divided into 4 groups, according to porcelain surface treatment: 1) no treatment, 2) mechanical retentions performed with diamond burs, 3) etching with phosphoric acid+silane, and 4) etching with hydrofluoric acid+silane. After being stored in distilled water at room temperature for one week, the specimens were submitted to a shear force (load) and the data were analyzed statistically (ANOVA). The means (in Mpa) of the groups were: 4.71 (group 1); 4.81 (group 2); 11.76 (group 3); 11.07 (group 4). There were no statistically significant differences between groups 1 and 2 and between groups 3 and 4

Tratamento endodôntico e protético de um incisivo central superior com dois canais radiculares / Endodontic and prosthetic treatment of a maxillary central incisor with two root canals

Neste trabalho é apresentado um caso clínico de tratamento endodôntico e protético de um incisivo central superior direito com dois canais radiculares

Prótese total maxilomandibular em pacientes submetidos à mandibulectomia segmentar / The total prothesis maxillomandibular in pacient submetid to ameloblastome

Os autores descrevem uma técnica para elaboraçäo de prótese maxilomandibular em paciente desdentada total, submetida a cirurgia de ameloblastoma na regiäo mentoniana esquerda, com necessidade de remoçäo de parte da mandíbula, após realizaçäo de implante do osso ilíaco. A elaboraçäo da prótese seguiu orientaçäo preconizada na Faculdade de Odontologia de Piracicaba, com ênfase à fase de moldagem funcional e ajuste oclusal, buscando maior estabilidade e retençäo da prótese sobre um tecido altamente comprometido pela ausência de rebordo alveolar

Reparación de protesis fijas plurales mediante aditamentos telescópicos / Repair of pleural fixed prosthesis using telescopic additions

La porcelana fundida sobre metal es la técnica restauradora más comúnmente aplicada en odontología. Su portencial de fracaso se debe en parte a las variables en la fabricación y su función. La finalidad del presente artículo es describir una reparación predecible para éstas restauraciones a través del manejo adecuado de superficies, el uso de un sobrecolado telescópico, y la aplicación de los principios de la odontología estética adhesiva

Effect of 4-META adhesive on bond strength and marginal seal of amalgam restorations and repairs--an in vitro study.

Amalgam remains unchallenged as a posterior restorative material. But its inability to bond to the teeth leads to some amount of microleakage at the restoration-tooth interface with associated problems such as post operative sensitivity, pulpal complications etc. Also a broken amalgam restoration requires replacement which will further weaken the tooth structure. Recently, 4-META has been introduced which can graft amalgam and composite to enamel, dentin and old amalgam restorations. In this study, the bonding and marginal sealing abilities of 4-META was assessed both at the tooth-amalgam interface and old amalgam fresh amalgam interface.