Effect of modeling liquids on resin composite roughness and color parameters after staining and toothbrushing

Abstract This study evaluated surface roughness, color stability, whitening index, and opacity of different types of modeling liquids for resin composite coating after exposure to staining and toothbrushing. Disc-shaped resin composite (Vittra APS, FGM) specimens were fabricated and divided into four groups (n = 10 each): control group, Composite Wetting resin (Ultradent Products), Adper Scotchbond Multipurpose adhesive (3M ESPE), and Adper Universal adhesive (3M ESPE). Surface roughness (Ra) was measured using a rugosimeter, while color stability (∆E00), whitening index (WI), and opacity (%) were measured using a spectrophotometer. Assessments were made at four time points: after polishing (baseline, T1), after immersion in red wine for 24 h (T2), and after 5,000 (T3) and 10,000 (T4) cycles of toothbrushing. Scanning electron microscopy images were captured to analyze the scratches created. The data were statistically analyzed by two-way repeated-measures analysis of variance and Tukey's honestly significant difference tests (α = .05). Modeling with the Wetting resin resulted in higher surface roughness (p < 0.05) and low color stability, which were attributable to porosities. Higher color change values were observed in the control group after staining. Both adhesives showed the lowest mean ΔE00 values (p < 0.005). WI decreased after staining, except with the use of the Universal adhesive (p < 0.005). The lowest opacity values were observed at baseline for all groups (p < 0.005). The Universal and Scotchbond adhesives had lower surface roughness, better color stability, higher WI, and the lowest opacity values after staining with red wine and toothbrushing.

Survival of atraumatic restorative treatment restorations in the elderly patients: a systematic review

Abstract: This study aimed to assess the survival of glass ionomer cement (GIC) restorations performed using the atraumatic restorative treatment (ART) in elderly patients. The systematic review protocol was registered in the PROSPERO database. The records were searched until August 2020 in eight electronic bibliographic databases, and included randomized and non-randomized clinical trials and observational studies, with no restrictions on the language or year of publication. Study selection and data extraction were performed independently by two reviewers. Data were extracted, summarized, collected for qualitative analysis, and evaluated for individual risk of bias using the Joanna Briggs Institute's Critical Appraisal Tool. The literature search retrieved 5,186 records; however, only seven studies fulfilled the eligibility criteria and were included. The studies were published between 2002 and 2019. A total of 1,239 restorations were investigated at intervals of 6, 12, 24, and 60 months of follow-up. Some studies had a low risk of bias, while others had moderate and high risk of bias. In general, GIC restorations placed using ART were considered satisfactory. The 6-month, 12-month, and 24-month survival rates ranged from 81.3% to 97.2%, 72.2% to 94%, and 63% to 87%, respectively; additionally, the survival rate for the longest follow-up period (60 months) was 85%. Given the best evidence-based information regarding caries removal, we highlight the need to provide a conservative and effective technique for use in elderly patients. ART is a promising and viable alternative that guarantees the survival of restorations in elderly patients.

Influência do desequilíbrio oclusal na origem de lesão cervical não cariosa e recessão gengival: análise por elementos finitos / Influence of occlusal instability on the origin of non-carious cervical lesion and gingival recession: finite element analysis

Objetivo: avaliar o comportamento biomecânico de pré- -molar superior com presença de Lesões Cervicais Não Cariosas (LCNC) e submetido a três carregamentos oclusais distintos pelo método de elementos finitos tridimensional (3D). Material e método: nove modelos tridimensionais elásticos foram gerados, com propriedades ortotrópicas e isotrópicas: Hígido (H); LCNC não restaurada (LCNC) e LCNC restaurada com resina composta (RC); sendo todos estes modelos submetidos a três carregamentos: Axial (A), Oblíquo vestibular (V) e Oblíquo palatino (P). Os carregamentos tiveram intensidade de 150 N e a restrição de deslocamento foi realizada na base e lateral dos ossos cortical e medular. Os resultados foram gerados em tensão máxima e mínima principal. Resultados: O carregamento axial apresentou padrões de tensão mais favoráveis, independente da característica da região cervical. O carregamento palatino mostrou maior acúmulo de tensão de tração na região cervical vestibular e o carregamento vestibular resultou em maior tensão de compressão na tábua óssea vestibular. A presença de LCNC foi fator intensificador para o aumento da concentração de tensão na região cervical. A simulação da restauração com resina composta promoveu um comportamento biomecânico simular ao do hígido. Conclusões: que o carregamento palatino pode estar mais associado com a presença de LCNCs e o vestibular com a presença de recessão gengival. O ajuste oclusal e a restauração da LCNC são indicados para tornar o padrão de tensão mais favorável para o remanescente dentário.

Objective: to evaluate the biomechanical behavior of maxillary premolar with the presence of NCCL and submitted to three distinct occlusal loads, using the three-dimensional (3D) finite element analysis. Methods: nine three-dimensional elastic models were generated, with orthotropic and isotropic properties: Sound (H); Unrestored NCCL (NCCL) and NCCL restored with composite resin (RC); All models were submitted to three loads: Axial (A), Buccal (V) and Palataline (P). The loads intensity was 150 N and the displacement restriction was performed at the base and lateral of the cortical and medullary bones. The results were generated at maximum and minimum principal stress. Results: the axial loading presented more favorable stress pattern, independent of the characteristic of the cervical region. The palataline loading showed a greater concentration of tensile stress in the buccal cervical region and the buccal loading resulted in a higher compression stress in the buccal bone. The presence of NCCL was a relevant factor for increase concentration of stress in the cervical region. The simulation of the restoration with composite resin promoted a biomechanical behavior similar to that of the sound tooth. Conclusion that the palataline loading may be more associated with the presence of NCCLs and the vestibular with the presence of gingival recession. The occlusal adjustment and the restoration of NCCLs are indicated to produce the stress pattern more favorable for the dental remaining.

Mock-up: previsibilidade e facilitador das Restaurações estéticas em resina composta / Mock-up: predictability and facilitator of restorations aesthetic in composite resin

A reabilitação oral funcional e estética por meio de procedimentos adesivos é uma alternativa para os pacientes insatisfeitos com seu sorriso. O planejamento e a previsibilidade dos tratamentos estéticos são essenciais para o sucesso destas reabilitações. Desta forma, o profissional pode lançar mão de alguns artifícios para auxiliar no planejamento e resultar emmaior previsibilidade. Dentre esses, o enceramento diagnóstico ou wax-up, que possibilita reproduzir as características dentárias, por meio do ensaio restaurador intraoral, denominado mock-up. O wax-up e o mock-up possibilitam a visualização tridimensional do resultado estético final por meio de técnica simples e rápida. Objetivo: apresentar relato de caso clínico mostrando a importância do planejamento reverso na reabilitação estética, realizada por meio de facetas diretas em resina composta. Caso clínico: paciente do gênero feminino, com 21 anos de idade e insatisfeito com a estética do seu sorriso. Ao exame clínico foi observado alteração da cor, forma e alinhamento dos dentes. Após a anamnese, exame clínico e planejamento, por meio de enceramento diagnóstico e ensaio restaurador, foi planejado a realização de clareamento utilizando a técnica de consultório e transformação dos dentes anteriores por meio de facetas diretas em resina composta. Conclusão: o planejamento da reabilitação oral com a utilização do mock-up resultou em motivação do paciente e maior previsibilidade do resultado final, além de maior segurança na execução do caso tanto para o cirurgião dentista quanto para o paciente

The aesthetic and functional rehabilitation by adhesive procedures is an alternative for patients dissatisfied with the smile. Even contemplating a conservative and reversible treatment, the outcome predictability of some aesthetic rehabilitation treatments is extremely important. Thus, the professional can make use of some devices to planning and obtaining predictability. The waxup reproduces the dental characteristics and intra-oral Restorative test is the mock-up. The wax-up or mock-up enables threedimensional visualization of the final restoration. Objective: This article aims clinical case report associating reverse planning and aesthetic rehabilitation by composite resin using stratified technique. Case report: A 21-year-old female patient reported dissatisfaction with the aesthetics of her smile. The clinical examination showed alteration of color, shape and teeth aesthetic. After the anamnesis and clinical examination, it was proposed to perform whitening with office technique and the reshape of the anterior teeth by resin composite veneer. Conclusion: The use of mock-up in reverse planning motivates the patient by generating greater predictability of the final treatment result and provides for the dentist safety execution.

Influence of preheating and post-curing on a novel fiber-reinforced composite post material

Abstract The aim of this study was to investigate the influence of preheating and post-curing methods on diametral tensile strength (DTS), flexural strength (FS), knoop microhardness (KHN), and degree of conversion (DC) of an experimental fiber-reinforced composite (FRC). Specimens (30 wt% of 3-mm-short E-glass fiber, 22.5 wt% of methacrylated-based resin and 47.5 wt% of filler particles) were subjected to: P - photocuring at 1500 mW/cm2 for 40 s (control); P/M - photocuring and microwave post-curing (540W/5 minutes); P/A - photocuring and autoclave post-curing (120°C/15 minutes); PH-P - preheating (60°C) and photocuring; PH-P/M - preheating, photocuring and microwave post-curing; and PH-P/A - preheating, photocuring and autoclave post-curing. Specimens for DTS (Ø 3 x 6 mm) and FS (25 x 2 x 2 mm) were tested at Instron 5965. KHN employed a 50g load for 30s. DC was measured using FTIR spectroscopy. Statistical analysis employed: factorial analysis, normality test, one-way ANOVA and Tukey's HSD test, independent T-test and the Dunnett test. Interaction between factors was not significant (P>0.05). Preheating promoted significantly higher values of FS and KHN (p = 0.0001). Post-curing promoted significantly higher values for KHN (p = 0.0001). For DTS (p = 0.066) and DC (p= 0.724) no statistical difference was found between groups. SEM images showed that preheating promoted better interaction between glass fibers and resin matrix. Preheating increased FS, KHN and DTS, and post-curing increased KHN. DC was not affected by both methods. Preheating and post-curing methods can be used to improve some mechanical properties of FRCs' but degree of conversion remains unaffected.

Minimally invasive approach in esthetic dentistry: composite resin versus ceramics veneers / Abordagem minimamente invasiva em odontologia estética: resina composta versus facetas cerâmicas

Unsatisfactory anatomical shape of anterior tooth promotes disharmony in the smile esthetics. The conservative dental esthetic reestablishment treatments has been improved and evaluated with the development of adhesive materials. The adhesive dentistry allowed minimally invasive preparation through direct treatments with composite resin and indirect ceramic laminates veneers. These two treatments methods present advantages and disadvantages. The aim of this manuscript is to describe two clinical reports and compare alternatives to rehabilitate the smile esthetic appearance by direct and indirect minimally invasive treatments. In the first case, a 24-years-old patient, female, complained of unsatisfactory anterior maxillary size and incisal wear. After the functional and esthetic planning, nanoparticle composite resin by free hand technique was indicated to rehabilitation. In the second case, a 24-years-old patient, male, reported dissatisfied with his anterior central incisive shape. On clinical examination, maxillary anterior conoid teeth were verified. Based on this evaluation, a conservative treatment using minimally invasive ceramic veneers in maxillary central and lateral incisor and ceramic fragments on canine was planed to the smile rehabilitation. It can be concluded that conservative treatment using direct composite resin restorations and minimum thickness ceramic veneers laminate, even with their specific limitations and advantages, provide satisfactory esthetic and functional treatment results, preserving the dental structure.

Dentes com formato anatômico insatisfatório podem causar desarmonia na estética do sorriso. Os tratamentos para restabelecer a estética do sorriso vêm evoluindo concomitantemente com o desenvolvimento dos materiais dentários. A odontologia estética permite um preparo minimamente invasivo através de resinas compostas e laminados cerâmicos. Estes dois métodos de tratamento apresentam algumas vantagens e desvantagens. O objetivo deste artigo é descrever dois relatos de casos clínicos e comparar alternativas para a reabilitação da estética do sorriso pelos tratamentos minimamente invasivos diretos e indiretos. No primeiro caso, paciente de 24 anos do gênero feminino, estava descontente com o tamanho e com o desgaste incisal dos dentes maxilares anteriores. Após o planejamento funcional e estético foi indicado restauração direta com uma resina nanopartículada pela técnica da mão livre. No segundo caso, paciente de 24 anos do gênero masculino relatou insatisfação com a forma dos incisivos centrais superiores. No exame clínico foi observado incisivos conoídes. Baseado no exame clínico foi planejado um tratamento conservador com laminados cerâmicos nos incisivos centrais e laterais, e fragmentos cerâmicos nos caninos. Pode-se concluir que os tratamentos conservadores utilizando resina composta e laminados cerâmicos, mesmo com suas limitações, promove uma estética satisfatória e resultados funcionais preservando a estrutura dental.

Reabilitação funcional e estética do sorriso û relato de caso / Functional and aesthetic rehabilitation of smile û case report

A constante busca por tratamentos odontológicos estéticos e por um sorriso bonito e harmônico é o que a maioria das pessoas almeja, o que contribui para a realização de procedimentos restauradores que possibilitem mimetização do natural para atingir as expectativas e necessidades dos pacientes. A presença de diastemas pode resultar em problemas funcionais e estéticos. Sendo assim, o presente caso clínico relata reabilitação de um extenso diastema entre os incisivos centrais superiores, após intervenção cirúrgica para remoção do freio labial e clareamento dental. Foram realizadas restaurações diretas minimamente invasivas nos dentes anteriores, com resina composta nanoparticulada. O acabamento e polimento foram realizados de forma a evidenciar anatomia e textura de superfície dos dentes. Em conclusão, o tratamento realizado utilizou materiais com comportamento biomecânico favorável, estabelecendo função, harmonia do sorriso e resultado estético satisfatório...

The constant search for dental aesthetic treatments in order to achieve a nice and harmonic smile has contributed to the development of restorative procedures enabling mimicry of natural teeth to meet expectations and needs of patients. The presence of diastemas can result in functional and aesthetic problems. Therefore, the present clinical case reports rehabilitation of a large diastema between the maxillary central incisors, after surgery for removal of labial frenum and tooth bleaching. Minimally invasive direct restorations were performed in anterior teeth with nanofilled composite resin. Finishing and polishing were done in order to demonstrate anatomy and surface texture of the teeth. In conclusion, the treatment used materials with biomechanical behavior, setting function, harmony of the smile and satisfactory aesthetic result...

Harmonização do sorriso com facetas diretas em resina composta: relato de caso / Smile harmonization with direct composite resin: a case report

Atualmente é possível ter maior previsibilidade do tratamento reabilitador com utilização de materiais com propriedades que biomimetizam os tecidos dentários perdidos. Este trabalho objetiva relatar o caso clínico de um paciente jovem insatisfeito com o aspecto de seu sorriso, o qual apresentava comprometimento do formato e da coloração dos dentes anterossuperiores. Para a reabilitação foram realizados planejamento reverso, com protocolo fotográfico, wax-up e mock-up, clareamento dental externo pela técnica de consultório e reanatomização dentária com facetas diretas em resina composta nos dentes 13 ao 23, pela técnica de estratificação. Em conclusão, esta reabilitação funcional e estética proporcionou ao paciente harmonia em seu sorriso, autoestima e satisfação com o resultado final alcançado...

Currently it is possible to have greater predictability of the rehabilitation treatment, through the use of materials with properties that resemble the lost dental tissue. This work aims to report the case of a young patient unsatisfied with the appearance of her smile, with format change and discoloration of the anterior teeth. For the rehabilitation, a reverse planning was carried out, through the use of a photographic protocol, wax-up and mock-up, external tooth bleaching and direct restorations on teeth #13 to #23, by a layering technique. In conclusion, this functional and aesthetic rehabilitation provided the patient’s smile harmony, self-esteem and satisfaction with the final result achieved...

Reabilitação estética de dente fraturado û relato de caso / Aesthetic rehabilitation of fractured tooth û case report

Traumatismo em dentes anteriores é queixa comum nos consultórios odontológicos e pode estar associado a fraturas coronárias, o que resulta em comprometimento da função e estética. As principais técnicas para reconstrução de dentes fraturados utilizam materiais restauradores adesivos diretos por possuírem propriedades físicas e mecânicas semelhantes à estrutura dentária, além de ser técnica minimamente invasiva. O presente artigo relata um caso clínico de restauração em dente anterior fraturado, utilizando resina composta nanoparticulada associada ao clareamento dental. O tratamento realizado possibilitou restabelecer função e devolver a harmonia e estética do sorriso...

Traumatic injuries in anterior teeth are a common complaint in the dental office. These traumas can result in crown fractures causing impairment of aesthetics and function. The main techniques for reconstruction of fractured teeth include the use of direct adhesive restorative materials because of their physical and mechanical properties that are similar to the tooth structure and minimally invasive technique. This article reports a clinical case of restoration in fractured anterior teeth using composite resin with dental bleaching. The result was satisfactory because they restored function and a harmonic smile...

Does the Moment of Fiber Post Cutting Influence on the Retention to Root Dentin?

Despite several advantages associated with pre-fabricated glass-fiber posts, the coronal portion of these posts must be cut to allow their use in various clinical situations. However, cutting the cemented post can generate stress on the bonding interface and affect the bond strength. The aim of this study was to investigate the effect the of fiber post cutting on the bond strength of root canals. Sixty bovine incisor roots were included in resin cylinders with simulated periodontal ligaments. Glass-fiber posts were luted using regular resin cement RelyX ARC (3M ESPE) or self-adhesive cement RelyX Unicem (3M ESPE). The posts were cut prior to cementation, immediately after luting or after building up the core (n=10). After storage for 24 h, the samples were cut and subject to push-out testing using a mechanical testing machine (EMIC DL 2000). Data were analyzed using two-way ANOVA (resin cement x moment of post cutting) and Tukey's post hoc test (α=0.05). The moment of fiber post cutting did not affect the bond strength when Unicem was used. However, the bond strength was reduced when ARC was used and when the post was cut immediately. In conclusion, the moment of fiber post cutting may affect the retention of root canal posts when a regular resin cement is used.

Apesar das diversas vantagens associadas aos pinos de fibra de vidro pré-fabricados, o corte da sua porção coronária deve ser realizado para permitir seu uso em algumas situações clínicas. Entretanto, o corte do pino cimentado pode gerar tensões na interface adesiva e afetar a resistência de união. O objetivo deste estudo foi avaliar o efeito do momento do corte do pino na resistência de união ao canal radicular. Sessenta raízes de incisivos bovinos foram incluídas em cilindros de resina com simulação do ligamento periodontal. Pinos de fibra de vidro foram cimentados utilizando um cimento resinoso convencional RelyX ARC (3M ESPE) ou autoadesivo RelyX Unicem (3M ESPE). Os pinos foram cortados previamente à cimentação, imediatamente após a cimentação, ou após a reconstrução do núcleo de preenchimento (n=10). Após o armazenamento por 24 h, as amostras foram seccionadas e submetidas ao ensaio de cisalhamento por extrusão utilizando máquina de ensaio mecânico (EMIC DL 2000). Os dados foram analisados por ANOVA dois fatores (cimento resinoso x momento do corte do pino) e teste de Tukey (=0,05). O momento do corte do pino de fibra de vidro não afetou a resistência de união quando o RelyX Unicem foi utilizado. No entanto, o corte do pino imediatamente após a cimentação reduziu os valores de resistência de união quando o RelyX ARC foi utilizado. Em conclusão, o momento do corte do pino pode afetar a resistência de união ao canal radicular quando o cimento resinoso convencional for utilizado.

Efeito da técnica de polimento na topografia de superfície e na transmitância da resina composta / Effect of polishing technique on the surface topography and transmittance of the composite resin

Introdução: Clinicamente, é comum observar os efeitos de estratificação de restaurações de compósito apenas após o polimento. Objetivo: Avaliar o efeito da técnica de polimento na transmitância de luz e na topografia de superfície de uma resina composta. Material e método: Amostras da resina Filtek Z-350 XT (cor A1E) foram confeccionadas em matriz metálica. Uma das superfícies das amostras recebeu acabamento com brocas de 12 lâminas e polimento através de uma das seguintes técnicas: SL (Sof-Lex), EH (Enhance) e DH (DHPro). Ausência de polimento foi usada como controle. Após o polimento, as amostras deviam apresentar espessura final de 1 mm. A transmitância de luz foi avaliada através do espectrofotômetro, sendo considerada apenas a luz no espectro visível. A topografia de superfície foi avaliada através de interferometria a laser, com os parâmetros Sdq (híbrido), St (amplitude máxima) e As (média de picos e vales). Os dados (n=5) foram submetidos a ANOVA e teste SNK. O teste de correlação de Pearson correlacionou Sdq, St e Sa à transmitância (α=0,05). Resultado: Todos os sistemas de polimento aumentaram a transmitância de luz em relação ao controle, não havendo diferença entre estes. Apenas as amostras polidas com SL e DH apresentaram maiores valores de Sdq que o Controle. Já para os parâmetros St e Sa, EH mostrou menores valores que o controle. Sdq e St mostraram correlação significativa com transmitância. Conclusão: Todos os sistemas de polimento foram efetivos em aumentar a transmitância, sendo a redução dos valores Sdq e St relacionada a esta modificação. .

Introduction: Clinically, it is common to observe the effects of composite restorations stratification only after the polishing. Aim: This study evaluated the effect of polishing technique on light transmittance and surface topography of a composite resin. Material and method: Specimens of the composite resin Filtek Z-350 XT (color A1E) were built-up using a metal matrix. One of the specimens surfaces was finished with 12-blade burs and polished using one of following techniques: SL (Sof-Lex), EH (Enhance) and DH (DHPro). No polishing was used as control. After the polishing procedures, the samples were measured to check the final thickness (1 mm). The light transmittance was measured using a spectrophotometer connected to an integrating sphere, considered only light in the visible spectrum. The surface topography was measured by laser interferometer, assessing the parameters Sdq (hybrid), St (maximum amplitude) and Sa (average of peaks and valleys). Data (n=5) were submitted to ANOVA and SNK's test, while Pearson's correlation test was used to related Ssq, St and Sa to transmittance (α=0,05). Result: All polishing systems increased the light transmittance when compared to control, whereas no difference was observed between them. Only the samples polished with SL and DH showed lower Sdq values than control. Although for St and Sa parameters, EH showed lower values than those observed for control. Sdq and St showed significant correlation with transmittance. Conclusion: All polishing systems were effective to increase the transmittance, while the reduction of Sdq and St values were related to this modification. .

Effect of Silane Type and Air-Drying Temperature on Bonding Fiber Post to Composite Core and Resin Cement

This study evaluated the influence of silane type and temperature of silane application on push-out bond strength between fiberglass posts with composite resin core and resin cement. One hundred and sixty fiberglass posts (Exacto, Angelus) had the surface treated with hydrogen peroxide 24%. Posts were divided in 8 groups according to two study factors: air-drying temperature after silane application (room temperature and 60 ºC) and silane type: three pre-hydrolyzed - Silano (Angelus), Prosil (FGM), RelyX Ceramic Primer (3M ESPE) and one two-component silane - Silane Coupling Agent (Dentsply). The posts (n=10) for testing the bond strength between post and composite core were centered on a cylindrical plastic matrix and composite resin (Filtek Z250 XT, 3M ESPE) that was incrementally inserted and photoactivated. Eighty bovine incisor roots (n=10) were prepared for testing the bond strength between post and resin cement (RelyX U100, 3M ESPE) and received the fiberglass posts. Push-out test was used to measure the bond strength. Data were analyzed by two-way ANOVA followed by Tukey's test (a=0.05). ANOVA revealed that temperature and silane had no influence on bond strength between composite core and post. However, for bond strength between post and resin cement, the temperature increase resulted in a better performance for Silane Coupling Agent, Silano and RelyX Ceramic Primer. At room temperature Silane Coupling Agent showed the lowest bond strength. Effect of the warm air-drying is dependent on the silane composition. In conclusion, the use of silane is influenced by wettability of resinous materials and pre-hydrolyzed silanes are more stable compared with the two-bottle silane.

Este estudo avaliou a influência do tipo de silano e a aplicação de temperatura no silano na resistência de união por push-out entre pinos de fibra de vidro com núcleo de preenchimento em resina composta e cimento resinoso. Cento e sessenta pinos de fibra de vidro (Exacto, Angelus, Londrina, PR, Brasil) receberam tratamento de superfície com peróxido de hidrogênio a 24%. Os pinos foram divididos em 8 grupos com dois fatores em estudo: temperatura de secagem de ar após a aplicação do silano (temperatura ambiente e 60 ºC) e o tipo de silano: três pré-hidrolisados - Silano (Angelus), Prosil (FGM), RelyX Ceramic Primer (3M ESPE) e um silano de dois frascos - Silane Coupling Agent (Dentsply). Para o teste de resistência de união entre pino e núcleo de preenchimento, os pinos (n=10) foram centralizados em uma matriz plástica cilíndrica e a resina composta (Filtek Z250 XT, 3M ESPE) foi incrementalmente inserida e fotopolimerizada. Para o teste de resistência de união entre pino e cimento resinoso (RelyX U100, 3M ESPE) 80 raízes de incisivos bovinos (n=10) foram preparadas e receberam os pinos de fibra de vidro. Teste de push-out foi usado para mensurar a resistência de união. Os dados foram analisados por ANOVA fatorial seguido do teste de Tukey (a=0,05). Temperatura e silano não tiveram influência na resistência de união entre núcleo de preenchimento e pino. Entretanto, para a resistência de união entre pino e cimento resinoso, o aumento da temperatura resultou em um melhor desempenho para Silane Coupling Agent, Silano e RelyX Ceramic Primer. Além disso, na temperatura ambiente Silane Coupling Agent teve a menor resistência de união. O efeito da secagem de ar quente é dependente da composição do silano. Concluindo, o uso do silano é influenciado pela molhabilidade dos materiais resinosos e os silanos pré-hidrolisados são mais estáveis comparados ao silano de dois frascos.

Critical analysis of fiber post surface treatment: a review / Análise crítica do tratamento de superfície de pinos de fibra: uma revisão

The surface treatment of fiber posts influence the bonding between composite resin cements and intraradicular retainers, being relevant to the prognostic of teeth without coronal structure. This study aimed to evaluate the different fiber post surface treatment protocols described on literature. The search strategy included a review of PubMed/MEDLINE database using fiber post associated with adhesion; bonding; surface treatment; as keywords. Papers not comprehending English language; assessment of post surface treatment; or testing of materials and their physicmechanical properties were excluded. Studies about glass and quartz fiber post surface treatment were considered for this literature review. Among the 190 articles included, silane agent was the material most used (60.52%) for the surface treatment of fiber posts, followed by application of alcoholic solutions (38.29%), and primer and/or adhesive systems (36.84%). Sandblasting of post surface was mentioned in (17.89%), but it affected the physical and mechanical properties. Hydrogen peroxide was mentioned only in 5.78% and it was shown to result on adequate exposure of the glass fibers without damaging them. It was concluded that a consensus for fiber post surface treatment still not exist in the current literature. Among the protocols described, the one using hydrogen peroxide followed by application of silane seems the most promising, since it allows increased bond strengths without fiber damage.

O processo de tratamento da superfície de pinos pré-fabricados de fibra influencia na união entre cimentos resinosos e esses retentores intra-radiculares, sendo relevante para o prognóstico do tratamento restaurador de dentes sem remanescente coronário. Este estudo objetivou avaliar diferentes protocolos de tratamentos de superfície para pinos de fibra descritos na literatura. Como metodologia, realizou levantamento bibliográfico na plataforma PubMed/MEDLINE, com a palavras-chave fiber post associada à adhesion; bonding; surface treatment. Excluíram-se artigos não redigidos em inglês; que não trataram a superfície do pino; e testes de propriedades físicas-mecânicas. Estudos que trataram a superfície de pinos de fibra de quartzo ou vidro foram incluídos. Dentre os 190 artigos incluídos nesta revisão, o agente silano foi o material mais utilizado (60.52%) para tratamento de superfície de pinos de fibra, seguido pela aplicação de álcool (38.29%), e sistema adesivo (36.84%). O jateamento do pino foi mencionado em 17.89%, mas esta técnica resultou em alteração das propriedades físicas e mecânicas. O peróxido de hidrogênio foi mencionado em 5.78% dos manuscritos, entretanto este tratamento permite a adequada exposição das fibras sem danificá-las. Concluiu-se que não consta na literatura protocolo padrão do tratamento da superfície de pinos de fibra. Dentre os protocolos descritos, o protocolo utilizando peróxido de hidrogênio seguido da aplicação do silano aparece como o mais promissor, pois permite resistência de união aumentada sem promover danos as fibras.

Transformação do sorriso por meio de fechamento de diastema utilizando resina composta nanoparticulada - relato de caso / Smile transformation through diastema closure using composite nanofilled - case report

A presença de diastema entre os dentes anteriores pode gerar desarmonia do sorriso e comprometer a estética do paciente. Com a evolução dos materiais e das técnicas restauradoras, o fechamento de diastema empregando resinas compostas tornou-se alternativa viável para resolução da maioria dos casos clínicos. Este tratamento permite restabelecer a função, possibilitando os contatos interproximais, bem como restabelecimento da estética, proporcionando um sorriso mais harmônico e agradável. Este artigo tem como objetivo relatar um caso clínico de correção de diastemas nos dentes anteriores superiores, utilizando resina composta nanoparticulada pela técnica direta para restabelecimento funcional e estético. O caso foi acompanhado por quatro anos, sendo realizados alguns reparos ao longo desse tempo, demonstrando que o fechamento de diastema com resina composta ‚ uma técnica viável e confiável, além de apresentar boa longevidade

The presence of anterior diastema can result on smile disharmony and compromise the patient’s aesthetic. The evolution of dental materials and techniques has made the use of composite resin for diastema closure a viable option treatment for most clinical cases. It restores function allowing the interproximal contacts, as well as harmony, reestablishing of the smile’s aesthetic. This clinical report aims at demonstrating the clinical correction of an anterior diastema restoring the functional anatomy and especially aesthetic through nanofilled composite resin restorations. The case was followed for 4-years and some repairs were carried out over this time, demonstrating the reliability and viability of the technique, with good longevity of the treatment

Effect of Surface Treatment of Fiberglass Posts on Bond Strength to Root Dentin

This study evaluated the influence of the surface treatments of fiberglass posts on bond strength to root dentin using push-out test. Forty bovine incisor roots were endodontically treated. The surface of the fiberglass posts (Exacto #2, Angelus) were treated using 4 different protocols (n=10): Control - 70% ethanol for 1 min; 37% phosphoric acid for 1 min; 10% hydrofluoric acid for 1 min; and 24% hydrogen peroxide for 1 min. After a silane coupling agent was applied for 1 min and all posts were cemented using self-adhesive resin cement (RelyX Unicem, 3M-ESPE). The roots were sectioned and two 1-mm-thick slices were obtained from each third: cervical, middle and apical. The specimens were subjected to the push-out test with a crosshead speed of 0.5 mm/min. Data were analyzed by repeated measures ANOVA followed by Tukey's HSD tests (=0.05). The surface treatment (p<0.001) and root third region (p=0.007) factors were significant. The retention to root canal was affected by surface treatment type. The post surface treatment with 24% hydrogen peroxide for 1 min yielded significantly higher bond strength when the fiberglass posts were cemented with RelyX Unicem.

Este estudo avaliou a influência de tratamentos de superfície de pinos de fibra de vidro na resistência de união à dentina radicular por meio do teste de push-out. Quarenta raízes de incisivos bovinos foram submetidas a tratamento endodôntico. A superfície dos pinos de fibra de vidro (Exacto #2, Angelus) foram tratadas com 4 protocolos diferentes (n=10): Controle - 70 % de etanol durante 1 min; 37 % de ácido fosfórico durante 1 min, 10% de ácido fluorídrico durante 1 min e 24 % de peróxido de hidrogênio durante 1 min. Depois foi aplicado agente de união silano por 1 min e todos os pinos foram cimentados com cimento resinoso auto-adesivo (RelyX Unicem, 3M- ESPE). As raízes foram seccionadas e foram obtidas duas fatias de 1 mm de espessura em cada terço: cervical, médio e apical. Os espécimes foram submetidos ao teste de push-out com uma velocidade de 0.5 mm/min. Os dados foram analisados pelo teste ANOVA com medidas repetidas, seguido pelo teste de Tukey HSD (=0,05). Os fatores tratamento de superfície (p<0,001) e região do terço radicular (p=0,007) foram significantes; no entanto, a interação entre os dois fatores não foi significante (p=0,827). A retenção ao canal radicular foi afetada pelo tipo de tratamento de superfície. O tratamento de superfície com 24% de peróxido de hidrogênio por 1 min rendeu significativamente maior resistência de união quando os pinos de fibra de vidro foram cimentados com RelyX Unicem.

Intra-radicular dentin treatments and retention of fiber posts with self-adhesive resin cements

The aim of this study was to evaluate the effect of treating intraradicular dentin with irrigating solutions on the retention of glass-fiber posts luted with self-adhesive resin cement. Bovine incisors were endodontically treated, and 9-mm-deep postholes were prepared. Before inserting the cement, the root canals were irrigated with various solutions: 11.5% polyacrylic acid for 30 s, 17% EDTA for 60 s, or 5% NaOCl for 60 s, respectively. Irrigation with distilled water was used in the control group. After all specimens had been rinsed with distilled water, the excess moisture was removed and the posts were luted using either BisCem (Bisco) or RelyX Unicem clicker (3M ESPE). Seven days after luting, the specimens were sectioned transversally into 1-mm-thick slices, which were submitted to push-out testing on a mechanical testing machine. Bond strength data (n = 6 per group) were analyzed by two-way ANOVA and Student-Newman-Keuls' test (α = 0.05). For Unicem, EDTA showed lower bond strength than the other solutions, which had similar results. For BisCem, EDTA showed higher bond strength than the other treatments, while application of NaOCl yielded higher bond strength than polyacrylic acid whereas the control group had intermediate results. In conclusion, irrigating root canals before insertion of self-adhesive resin cements, especially EDTA, might interfere with retention of the fiber posts.

Effect of relining on fiber post retention to root canal

One of the clinically relevant problems dentists face when restoring endodontically treated teeth is the mismatch between fiber post and post space diameters, which results in an excessively thick resin cement layer. Fiber post relining appears as a solution for this problem. OBJECTIVES: The aim of this study was to evaluate the effect of fiber post relining with composite resin on push-out bond strength. MATERIAL AND METHODS: Twenty bovine incisors were selected to assess post retention. The crowns were removed below the cementoenamel junction and the root canals were treated endodontically and flared with diamond burs. The roots were allocated into two groups (n=10): G1: fiber posts without relining and G2: fiber posts relined with composite resin. The posts were cemented with a dual-cured resin cement and the specimens were sectioned transversally. Three 1.5-mm thick slabs were obtained per root and identified as cervical, medium and apical thirds. The push-out test was performed at a crosshead speed of 0.5 mm/min until post dislodgement occurred. The failure mode of fractured specimens was analyzed under scanning electron microscopy. Data were analyzed by split-plot ANOVA and post-hoc Tukey's test at a pre-set alpha of 0.05. RESULTS: Relined fiber posts presented higher retention values than non-relined post in all thirds. No statistically significant differences (p>0.05) were found among thirds for relined posts. All failures occurred at the interface between resin cement and root dentin. CONCLUSIONS: Relining with composite resin seems to be an effective method to improve the retention of fiber posts to flared root canals.

Influence of root depth and the post type on Knoop hardness of a dual-cured resin cement

Fiber posts are usually luted to the root canal with dual-cured resin cements. However, some of these cements require light-activation in order to reach optimal degree of cure. The aim of this study was to evaluate the effect of the fiber post type on microhardness of a dualcured resin cement used for luting these posts. After endodontic treatment, four fiber post types were luted to the root canal of bovine incisors with RelyX ARC. The samples were sectioned in order to obtain four slices, representing different depths (0.0; 2.5; 5.0; 7.5 and 10.0mm). Knoop microhardness testing was performed in eachslice. The data were submitted to split-plot ANOVA and Tukey post-hoc tests. An additional sample per fiber post type was used to analyze bonding interface by SEM. At the depths of 0 and 2.5 mm, the resin cement presented the highest hardness values. The lowest values were observed at the 10 mm depth, and the resin cement presented intermediary hardness means at the depths of 5 mm and 7.5 mm. By means of scanning electronic microscopy, it was possibleto see the more homogeneous hybrid layer in the cervical region of the root.