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

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.

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.

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.

Effect of Interval Time between Corrosive and Abrasive Challenges on a Nanoparticulate Composite Resin.

OBJECTIVE: This study aimed to evaluate the effect of interval time after acidic beverage intake and brushing on roughness and hardness of resin composite. MATERIALS AND METHODS: Nanofilled resin composites were tested as per interval time (no interval, 15 or 30 minutes) between aging media (isotonic, sports drink) and brushing. Specimens (n = 9) were subjected to three cycles daily for 5 days with immersion in beverage followed by simulated brushing (585 strokes). The brushing (control) group was submitted only in brushing cycles. Roughness and microhardness were analyzed in the baseline and end of the experiment. Surface morphology was analyzed by using scanning electron microscopy (SEM). STATISTICAL ANALYSIS: Data were analyzed by one-way ANOVA and Tukey's honestly significant difference (α = 0.05). RESULTS: Roughness was higher in no interval group and lower in 30 minutes and control. The 15 minutes present no statistical difference between control, 30 minutes and no interval. The hardness not present difference between groups. The SEM showed the no interval more roughness than 15 and 30 minutes, control and baseline. CONCLUSION: The interval time between erosive and abrasive challenge is important to preserve the smoothness surface of composite resin.

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.

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

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.

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.

An Experimental Thermally Deposited Coating for Improved Bonding to Glass-fiber Posts.

PURPOSE: To determine whether an experimental thermally deposited siloxane-methacrylate coating for use in industrial scale applications would improve the bond strength of resin-based materials to glass fiber posts (GFPs) without affecting their mechanical properties. MATERIALS AND METHODS: An experimental 5% (w/v) solution of methacryloxypropyltrimethoxysilane was prepared. Two types of GFPs (Exacto, Angelus; White Post DC, FGM) were divided into the following groups: S: silane; SA: silane and adhesive; HS: 35% H2O2 and silane; HSA: 35% H2O2, silane and adhesive; Exp: siloxane-methacrylate coating (Si-O) via post immersion in experimental solution followed by heating; Exp-S: silane after Si-O treatment; Exp-A: adhesive after Si-O treatment; and Exp-SA: silane and adhesive after Si-O treatment. The posts were positioned in a mold to allow insertion of a dual-curing resin core, serially sectioned into beams, and subjected to microtensile bond strength (µTSB) testing. The three-point bending test and SEM/EDX analysis were used to assess the mechanical and surface properties of untreated GFPs that were etched with H2O2 or treated with Si-O. RESULTS: Surface treatments affected the µTSB only for the Exacto GFPs. The highest µTBS (MPa) was observed in Exp-S and Exp-SA groups, whereas H2O2 etching resulted in intermediate values. The mechanical properties were not affected by surface treatments. Exacto GFPs had significantly higher flexural strength (σf) and flexural modulus (Ef) than did the White Post DC GFPs, but the latter were significantly stiffer (S) than Exacto, regardless of the surface treatment tested. H2O2 promoted morphological changes in post surfaces. The experimental treatment promoted deposition of Si onto the post surface, improving bond strengths of Exacto posts. CONCLUSION: The proposed novel coating technique is a viable procedure for fiber post manufacturers to improve the µTSB of resin-based materials.

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...

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.

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.

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...

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 (α=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.

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.

Immediate and delayed photoactivation of self-adhesive resin cements and retention of glass-fiber posts.

The aim of this study was to evaluate the effect of immediate and delayed photoactivation of self-adhesive resin cements (SARCs) on the retention of glass-fiber posts luted into root canals. Bovine incisors were endodontically treated, and post holes of 9 mm in depth were prepared. Fiber posts were luted using one of two SARCs, BisCem (Bisco Inc., Schaumburg, USA) or RelyX Unicem clicker (3M ESPE, Saint Paul, USA), or a regular (etch-and-rinse) resin cement (AllCem; FGM, Joinvile, Brazil). Photoactivation was performed immediately, or at 5 or 10 min after cementation. Root/post specimens were transversely sectioned 7 days after luting into 1-mm-thick slices, which were submitted to push-out testing in a mechanical testing machine. Bond strength data were analyzed by two-way ANOVA and Student-Newman-Keuls' method (α = 0.05). Immediate photoactivation resulted in the highest bond strength for Unicem. BisCem demonstrated higher bond strength values when photoactivated after a 10-min delay. Immediate photoactivation yielded the lowest bond strengths for AllCem, although no differences in bond strength were observed between photoactivation delayed by 5 and 10 min. In conclusion, the moment of resin cement photoactivation may affect the intraradicular retention of fiber posts, depending upon the resin cement used for luting.