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1.
Rev. Ciênc. Plur ; 9(1): 29634, 27 abr. 2023. ilus
Article in Portuguese | LILACS, BBO | ID: biblio-1428369

ABSTRACT

Introdução:O aprimoramento das resinas compostas nos últimosanos em associação com a difusão de informações nas redes sociais tornou as facetas diretas tratamentos populares na dentística restauradora. No entanto, são procedimentos que exigem ampla destreza manual e conhecimento técnico. O fluxo digital através doescaneamento, enceramento digital e prototipagem 3D para construção de guias tem se tornado uma excelente alternativa para aumentar a previsibilidade e aumentar a longevidade destes trabalhos. Objetivo:Descrever o protocolo de confecção de facetas diretas em resina composta, através de um relato de caso, utilizando como auxílio o planejamento digital para confecção de modelo 3D, guia de silicone e paredes palatinas. Descrição do Caso:Paciente do gênero masculino, 43 anos, queixava-se do formato dos seus dentes. Ao exame clínico percebeu-se desgaste dental nos incisivos centrais e linha do sorriso levemente invertida. Após duas sessões de clareamento de consultório com Peróxido de hidrogênio (35%) e mockup direto com resina composta, foi realizada a moldagem e escaneamento do modelo de gesso no laboratório. O enceramento digital foi aprovado, o modelo 3D foi impresso para confecção da guia de silicone. Com auxílio da guia foram executadas facetas diretas nos elementos 13, 12, 11, 21, 22 e 23. Conclusão:O fluxo digital pode ser uma alternativa viável para minimizar as falhas na confecção de facetas diretas em resina composta (AU).


Introduction:The improvement of composite resins in recent years, together with information disseminated on social media, has made direct veneers popular treatments in restorative dentistry. However, these procedures require significant manual dexterity and technical knowledge. Digital work flow using scanning, digital wax-up and 3D prototyping for the construction of guides has become an excellent alternative to increase predictability and the longevity of these procedures. Objective:Describe the manufacturing protocol for direct composite resin veneers, using a case report and digital to construct the 3D model, silicone guide and palatine walls. Case description:Male patient, 43 years old, complained of the shape of his teeth. Clinical examination revealed tooth wear on the central incisors and a slightly inverted smile line. After two whitening sessions with hydroigen peroxide (35%) and direct mockup with composite resin, the plaster model was molded and scanned in the laboratory. Digital wax-up was approved, and the 3D model was printed to manufacture the silicone guide. With the help of the guide, the direct veneers were applied to elements 13, 12, 11, 21, 22 and 23.Conclusions:Digital flow may be a feasible alternative to minimize manufacturing flaws in direct composite resin veneers (AU).


Introducción: La mejora de las resinas compuestas en los últimos años, y la difusión de información en las redes sociales, ha popularizado las facetas directas en los tratamientos en odontología restauradora. Sin embargo, son procedimientos que requieren demasiado destreza manual y conocimientos técnicos. El flujo digital usando escaneo, encerado digital y prototipado 3D para la construcción de guías se ha convertido en una excelente alternativa para aumentar la previsibilidad y la longevidad de estos procedimientos. Objetivo: Describir el protocolo para la realización de carillas directas en resina compuesta, a través de un reporte de caso, utilizando el planeo digital como ayuda para la realización de un modelo 3D, guía de silicona y paredes palatinas. Descripción del caso: Paciente masculino, 43 años, se quejó de la forma de sus dientes. El examen clínico reveló desgaste dental en los incisivos centrales y una línea de sonrisa levemente invertida. Después de dos sesiones de blanqueamiento en consultorio con peróxido de hidrógeno (35%) y maqueta directa con resina compuesta, el modelo de yeso fue moldeado y escaneado en el laboratorio. El encerado digital fue aprovado, el modelo 3D fue impreso para hacer la guía de silicona. Con la ayuda de la guía se realizaron carillas directas en los elementos 13, 12, 11, 21, 22 y 23. Conclusiones: El fluxo digital puede ser una alternativa viable para minimizar fallas en la fabricación de carillas directas en resina compuesta (AU).


Subject(s)
Humans , Male , Adult , Computer-Aided Design/instrumentation , Composite Resins/chemistry , Dental Veneers , Esthetics, Dental , Photography, Dental/instrumentation , Hydrogen Peroxide/chemistry
2.
J. oral res. (Impresa) ; 11(5): 1-13, nov. 23, 2022. ilus, tab
Article in English | LILACS | ID: biblio-1436941

ABSTRACT

Objetive: To compare the clinical behavior of two types of Bulk Fill composite resins and a nanohybrid resin at 18 months in occlusal restorations. Material and Methods: Three occlusal restorations were performed in each one of the 55 participants. They were randomly distributed into three groups, TN: Tetric-N-Ceram Bulk-Fill, FK: Filtek Bulk-Fill, and Z350: Filtek Z350XT. Adhesive techniques and restorative procedures were performed according to the manufacturer's instructions for each restorative material used. In TN and FK an increment of 4mm was applied, and in Z350 increments of ≤2mm depth were applied. Two calibrated operators evaluated the restorations at baseline and at 18 months using the FDI World Dental Federations system (1: excellent, 2: good, 3: satisfactory, 4: unsatisfactory, 5: poor) for clinical marginal staining (MS) properties, fracture-retention (FR), superficial texture (ST), marginal integrity (MI), postoperative sensitivity (PS) and caries (C). Kruskal-Wallis and Wilcoxon were used to compare the 3 groups at 18 months (5% significance). Results: 38 patients with a total of 114 restorations were assessed, being evaluated with excellent clinical behavior; MI, 78.9% in Z350, 89.51% in TN and 81.6% in FK; ST 73.5% in Z350, 86.8% in TN, and 84.2% in FK; MS 84.2% in Z350, 84.2% in TN, and 91.2% in FK; PS 100% in Z350 and 97.3% in TN and FK; in C and FR, 100% in the 3 groups. There were no significant differences between the three groups (p>0.05). Conclusion: The three resins studied presented a good clinical performance at 18 months without showing significant differences in the clinical properties evaluated.


Objetivo: Comparar el comportamiento clínico a 18 meses en restauraciones oclusales entre dos tipos de resinas compuestas Bulk Fill y una resina nanohíbrida. Material y Métodos: En 55 participantes se realizaron 3 restauraciones oclusales en cada paciente, distribuidas aleatoriamente en 3 grupos, TN: Tetric-N-Ceram Bulk-Fill, FK: Filtek Bulk-Fill y Z350: Filtek Z350XT. Las técnicas adhesivas y procedimientos restauradores fueron realizados según las instrucciones de los fabricantes de cada material restaurador utilizado. En TN y FK se aplicó un incremento de 4mm y en Z350 se aplicó incrementos ≤ 2 mm de profundidad. Dos operadores calibrados evaluaron las restauraciones al baseline y a los 18 meses mediante el sistema FDI World Dental Federations (1: excelente, 2: aceptable, 3: suficiente, 4: insatisfactorio, 5: inaceptable) en las propiedades clínicas de tinción marginal (TM), fractura-retención (FR), textura superficial (TS), integridad marginal (IM), sensibilidad postoperatoria (SP) y caries (C). Se utilizó Kruskal-Wallis y Wilcoxon para la comparación de los 3 grupos a 18 meses (significancia de 5%). Resultados: Se controlaron 38 pacientes con un total de 114 restauraciones, siendo evaluados con comportamiento clínico excelente; IM, 78.9% en Z350, 89.51% en TN y 81.6% en FK; TS 73.5%, en Z350, 86.8% en TN y 84.2% en FK; TM, 84.2% en Z350, 84.2% en TN y 91.2% en FK; SP 100% en Z350 y 97,3% en TN y FK; en C y FR 100% en los 3 grupos. No hubo diferencias significativas entre los 3 grupos (p>0,05). Conclusión: Las 3 resinas estudiadas presentaron un buen desempeño clínico a 18 meses sin mostrar diferencias significativas en las propiedades clínicas evaluadas.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Composite Resins/chemistry , Dental Cements/chemistry , Dental Restoration, Permanent/methods , Chile/epidemiology , Resin Cements/chemistry , Dental Restoration Wear
3.
J. oral res. (Impresa) ; 11(4): 1-11, jul. 21, 2022. ilus, tab
Article in English | LILACS | ID: biblio-1426955

ABSTRACT

Aim: This study aims to evaluate the surface roughness and susceptibility to staining of bleached composite resin with 22% carbamide peroxide, as well as the effect of subsequent prophylaxis with NaHCO3 powder. Material and Methods: Forty disk-shaped (2 × 6 mm) specimens of composite resin (Z250 XT) were prepared. Half of the specimens were subjected to bleaching with 22% carbamide peroxide, and the other half were stored in artificial saliva. In sequence, all specimens were immersed in acai juice (Euterpe oleracea) for 4 h for 14 days, and subdivided into two groups. Group 1 samples were subjected to prophylaxis treatment, while group 2 samples were subjected to treatment with artificial saliva. Surface roughness (Ra) and color (ΔE*) were measured after polishing (T0), bleaching (T1), immersion in acai juice (T2), and application of NaHCO3 powder (T3) using a profilometer and a spectrophotometer. Results: Statistical analyses (analysis of variance and Tukey's test, p≤0.05) revealed that regarding color there was statistically significance for the factors in isolation, except for the factor bleaching. For both color and surface roughness there was statistically significant difference for the interaction, except for the interaction between NaHCO3 power and bleaching. Conclusion: The NaHCO3 air-powder polishing decreases the staining of the composite resin; however, it increases the surface roughness. With respect to the color variable, the whitening factor had no significant effect on the tested material; however, it increases surface roughness.


Objetivo: Este estudio tiene como objetivo evaluar la rugosidad de la superficie y la susceptibilidad a la tinción de la resina compuesta blanqueada con peróxido de carbamida al 22%, así como el efecto de la profilaxis posterior con polvo de NaHCO3. Material y Métodos: Se prepararon cuarenta especímenes en forma de disco (2 × 6 mm) de resina compuesta (Z250 XT). La mitad de los especímenes se sometieron a blanqueo con peróxido de carbamida al 22% y la otra mitad se almacenó en saliva artificial. En secuencia, todos los especímenes se sumergieron en jugo de acai (Euterpe oleracea) durante 4h durante 14 días, y se subdividieron en dos grupos. Las muestras del grupo 1 se sometieron a tratamiento profiláctico, mientras que las muestras del grupo 2 se sometieron a tratamiento con saliva artificial. La rugosidad de la superficie (Ra) y el color (ΔE*) se midieron después del pulido (T0), el blanqueo (T1), la inmersión en jugo de acai (T2) y la aplicación de polvo de NaHCO3 (T3) utilizando un perfilómetro y un espectrofotómetro. Resultados: Los análisis estadísticos (análisis de varianza y prueba de Tukey, p≤0.05) revelaron que en relación al color hubo significancia estadística para los factores en forma aislada, excepto para el factor blanqueamiento. Tanto para el color como para la rugosidad de la superficie hubo una diferencia estadísticamente significativa para la interacción, excepto para la interacción entre el poder de NaHCO3 y el blanqueo. Conclusión: El pulido al aire con polvo de NaHCO3 disminuye el manchado de la resina compuesta; sin embargo, aumenta la rugosidad de la superficie. Con respecto a la variable color, el factor de blanqueamiento no tuvo efecto significativo sobre el material ensayado; sin embargo, aumenta la rugosidad de la superficie.


Subject(s)
Humans , Sodium Bicarbonate , Composite Resins/chemistry , Saliva , Brazil , Color , Dental Prophylaxis/methods , Euterpe , Immersion
4.
J. oral res. (Impresa) ; 11(3): 1-11, jun. 30, 2022. ilus
Article in English | LILACS | ID: biblio-1427951

ABSTRACT

Objetive: To evaluate microleakage of composite resins (CR) placed over different cavitary liners after managing deep caries lesions through selective removal of soft carious tissue to soft dentin (SRCT-S). Material and Methods: Fifty four human teeth were collected for microleakage testing. Each assay comprised ICDAS 5 or ICDAS 6 carious lesions and sound teeth for controls. Sound teeth were prepared with cavities that mirrored the carious teeth cavities, which were prepared with SRCT-S. Sound and carious teeth were further randomly assigned to one of the three experimental groups: Group A: universal adhesive (UA) + CR, Group B: glass ionomer cement liner + UA + CR, and Group C: calcium hydroxide + UA+ CR. Occlusal microleakage (OM) and cervical microleakage (CM) was classified within one of 5 depth categories. ANOVA and Chi-square tests were computed (p<0.05). Results: OM and CM were similarly distributed across subgroups (p>0.05). All Group C samples with carious lesions presented some degree of microleakage. However, no statistically significant differences were observed between groups and within each group (p>0.05). Conclusion: Teeth restored with CR after SRCT-S using calcium hydroxide as a liner material seem to exhibit higher microleakage than those restored using glass ionomer or UA alone. Further clinical research is needed to deepen these findings. Clinical significance: The application of calcium hydroxide as a liner under a composite resin may reduce the longevity of a restoration after performing selective or partial removal of carious tissues. Clinicians should rethink the need of using calcium hydroxide for this application, albeit the lack of clinical evidence.


Objetivo: Evaluar la microfiltración de resinas compuestas (RC) colocadas sobre diferentes liners cavitarios después del manejo de lesiones de caries profundas mediante la remoción selectiva de tejido cariado blando hasta dentina blanda (SRCT-S). Material y Métodos: Se recolectaron 54 dientes humanos para pruebas de microfiltración. Cada ensayo comprendía lesiones cariosas ICDAS 5 o ICDAS 6 y dientes sanos para los controles. Se prepararon dientes sanos con cavidades que reflejaban las cavidades de los dientes cariados, que se prepararon con SRCT-S. Los dientes sanos y cariados se asignaron al azar a uno de los tres grupos experimentales: Grupo A: adhesivo universal (AU) + RC, Grupo B: revestimiento de cemento de ionómero de vidrio + AU + RC, y Grupo C: hidróxido de calcio + AU+ RC. La microfiltración oclusal (MO) y la microfiltración cervical (MC) se clasificaron dentro de una de las 5 categorías de profundidad. Se calcularon las pruebas ANOVA y Chi-cuadrado (p<0,05). Resultados: La MO y MC se distribuyeron de manera similar en los subgrupos (p> 0,05). Todas las muestras del Grupo C con lesiones cariosas presentaron algún grado de microfiltración. Sin embargo, no se observaron diferencias estadísticamente significativas entre grupos y dentro de cada grupo (p>0,05). Conclusión: Los dientes restaurados con RC después de SRCT-S usando hidróxido de calcio como material de revestimiento parecen exhibir una mayor microfiltración que aquellos restaurados usando ionómero de vidrio o AU solo. Se necesita más investigación clínica para profundizar estos hallazgos. Relevancia clínica: la aplicación de hidróxido de calcio como revestimiento debajo de una resina compuesta puede reducir la longevidad de una restauración después de realizar la eliminación selectiva o parcial de los tejidos cariados. Los médicos deberían reconsiderar la necesidad de usar hidróxido de calcio para esta aplicación, aunque no haya evidencia clínica.


Subject(s)
Humans , Composite Resins/chemistry , Dental Cavity Lining , Dental Leakage/classification , Glass Ionomer Cements/chemistry , Calcium Hydroxide , Intervention Studies , Resin Cements/chemistry , Dental Caries/therapy
5.
Pesqui. bras. odontopediatria clín. integr ; 22: e210110, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1422262

ABSTRACT

Abstract Objective: To evaluate the effect of two types of light-curing units (second and third generations) and two types of bulk-fill composite resins with different photoinitiators - Tetric N-Ceram Bulk Fill (TNCB) and Xtra Fil (XTF) on gap formation at the gingival margins of Cl II restorations. Material and Methods: Fifty-six standard Cl II cavities were prepared on the mesial and distal surfaces of premolar teeth, with the gingival margin of the cavities 1 mm apical to the CEJ. The samples were randomly assigned to two groups based on the composite resin type and two subgroups based on the light-curing unit type and restored. After 5000 rounds of thermocycling, gingival margin gap in each sample was measured in µm under an electron microscope at ×2000 magnification. Data were analyzed by two-way ANOVA and Tukey tests (α=0.05). Results: Marginal gaps of TNCB composite resin were significantly smaller than those of XTF composite resin (p<0.001). There were no significant differences between the two light-curing units in each group (p=0.887 with XTF and p=0.999 with TNCB). Conclusion: The gaps at gingival margins of Cl II cavities with TNCB bulk-fill composite were smaller than XTF composite resin. Both composite resins can be cured with both the second- and third-generation LEDs (AU).


Subject(s)
Humans , Bicuspid , Dental Marginal Adaptation , Composite Resins/chemistry , Light-Curing of Dental Adhesives/instrumentation , Photoinitiators, Dental/chemistry , In Vitro Techniques/methods , Microscopy, Electron, Scanning/instrumentation , Analysis of Variance
6.
Acta odontol. latinoam ; 33(2): 59-68, Sept. 2020. graf
Article in English | LILACS | ID: biblio-1130735

ABSTRACT

ABSTRACT The aim of this in vitro study was to evaluate the effect of bleaching protocols on the surface roughness (Ra), color change and surface micromorphology of a low-viscosity bulk-fill composite (Filtek Bulk Fill Flow, 3M ESPE), a highviscosity bulk-fill composite (Filtek Bulk Fill, 3M ESPE) and a conventional nanoparticulate composite resin (control) (Filtek Z350 XT, 3M ESPE). Forty samples of each composite (disks 5 mm in diameter and 2 mm thick) were randomly divided into four groups (n=10), according to bleaching protocol: a) 10% carbamide peroxide gel (Opalescence, Ultradent Products) (2 h/ day, for 14 days); b) 40% hydrogen peroxide gel (Opalescence Boost, Ultradent Products) (three bleaching sessions, once a week, 45 min/session); c) whitening rinse (Listerine Whitening Extreme, Johnson & Johnson) (2 min/day, for 14 days); and d) distilled water (control). The samples were submitted to triplicate readings (Ra and color [CIELAB parameters]) before and after contact with bleaching protocols. Micromorphology was analyzed in a scanning electron microscope (SEM). Ra and color parameters (ΔL, Δa, Δb and ΔE) were analyzed by generalized linear models (α=0.05). The Ra of the high-viscosity bulk-fill was significantly higher than that of the other composites (p<0.05). Ra increased significantly (p<0.05) and surface became more irregular (SEM analysis) in all the composite resins, regardless of the bleaching protocol (p<0.05). The high-viscosity bulk-fill composite resin group had significantly lower ΔE (p<0.05) than the nanoparticulate composite resin group immersed in distilled water. It was concluded that the characteristics of each resin significantly influenced the Ra more than the bleaching protocol. The high-viscosity bulk-fill resin presented minor color change.


RESUMO Este estudo in vitro teve objetivo de avaliar o efeito de protocolos clareadores sobre a rugosidade de superfície (Ra), alteração de cor e micromorfologia de resina bulk-fill de baixa viscosidade (Filtek Bulk Fill Flow, 3M ESPE), alta viscosidade (Filtek Bulk Fill, 3M ESPE) e de uma resina composta nanoparticulada (controle) (Filtek Z350 XT, 3M ESPE). Quarenta amostras de cada resin composta (discos de 5 mm de diâmetro e 2 mm de espessura) foram aleatoriamente divididas em quatro grupos , de acordo com protocolo clareador (n=10): a) Gel de peróxido de carbamida (Opalescence, Ultradent Products) (2 horas/dia, por 14 dias); b) Gel de peróxido de hidrogênio (Opalescence Boost, Ultradent Products) (3 sessões de clareamento, uma por semana, 45 min/sessão); enxaguatório clareador (Listerine Whitening Extreme, Johnson & Johnson) (2 min/dia, por 14 dias); d) água destilada (controle). As amostras foram submetidas a leituras, em triplicata (Ra e cor (parâmetros CIELab) antes e depois do contato com os protocolos clareadores. A micromorfologia de superfície foi conduzida em microscópio eletrônico de varredura (MEV). Ra e parâmetros de cor (ΔL, Δa, Δb e ΔE) foram analisados por modelos lineares generalizados (α=0.05). A Ra da resina bulk-fill de alta viscosidade foi significantemente superior do que para os outros compósitos (pp<0.05). A Ra aumentou significantemente (p<0.05) e a superfície ficou mais irregular (MEV) para todos os compósitos, independente do protocolo clareador (pp<0,05). A resina bulk-fill de alta viscosidade obteve menor ΔE (pp<0.05) do que a resina composta nanoparticulada, imersa em água destilada. Pode-se concluir que as características de cada resina composta influenciaram de forma mais significativa a Ra do que o protocolo clareador. A resina bulk fill de alta viscosidade apresentou menor alteração de cor.


Subject(s)
Humans , Tooth Bleaching/methods , Tooth Discoloration/drug therapy , Viscosity/drug effects , Composite Resins/chemistry , Tooth Bleaching Agents/chemistry , Hydrogen Peroxide/chemistry , Materials Testing , Color
7.
J. oral res. (Impresa) ; 9(4): 319-325, ago. 31, 2020. ilus, tab
Article in English | LILACS | ID: biblio-1179153

ABSTRACT

Purpose: This in vitro study aimed to evaluate the influence of dentin conditioning with polyacrylic acid on the shear bond strength of the nano-filled resin-modified glass ionomer cement Ketac N100 (3MESPE). Material and methods: Eighteen bovine incisors were randomly divided into two groups (n=18): group 1, without dentin surface treatment, and group 2, with dentin surface treated with 10% polyacrylic acid for 15 seconds. In both groups the primer was applied before the application of the nano-filled resin-modified glass ionomer cement (Ketac N100) and light-cured for 20 seconds. After 24 hours, the specimens were submitted to thermocycling for 350 cycles, and the teeth were immersed in distilled water at room temperature. After 24 hours, specimens were tested for shear bond strength at 1mm/minute crosshead speed. The collected data were analyzed using the non-parametric test of Mann Whitney (p<0.05). Results: There was a significant difference in shear bond strength values between the treatment and control groups, the group with dentin conditioning with 10% polyacrylic acid showed higher shear strength values than the group without dentin treatment. Conclusion: Application of 10% polyacrylic acid on dentin increases the shear bond strength values of nano-filled resin-modified glass ionomer cement.


Este estudio in vitrotuvo como objetivo evaluar la influencia del acondicionamiento de la dentina con ácido poliacrílico sobre la resistencia al cizallamiento del cemento de ionómero de vidrio modificado con resina con tecnología de nano relleno Ketac N100 (3MESPE). Material y Métodos: Dieciocho incisivos bovinos se dividieron aleatoriamente en dos grupos (n = 18): el grupo 1, sin tratamiento de la superficie dentinaria, y el grupo 2, con la superficie dentinaria tratada con ácido poliacrílico al 10% durante 15 segundos. En ambos grupos, el Primer se aplicó antes de la aplicación del cemento de ionómero devidrio modificado con resina con tecnología de nano relleno (Ketac N100) y se fotopolimerizó durante 20 segundos. Después de 24 horas, las muestras se sometieron a 350 ciclos de termociclado y los dientes se sumergieron en agua destilada a temperatura ambiente. Después de 24 horas, las muestras se evaluaron para determinar la resistencia al cizallamiento a una velocidad constante de 1 mm / minuto. Los datos recolectados fueron analizados mediante la prueba no paramétrica de Mann Whitney (p<0.05). Resultados: Hubo una diferencia significativa en los valores de resistencia al cizallamiento entre los grupos de tratamiento y control, el grupo con acondicionamiento de dentina con ácido poliacrílico al 10% mostró valores de resistencia al cizallamiento más altos que el grupo sin tratamiento de la dentina. Conclusión: La aplicación de ácido poliacrílico al 10% sobre la dentina aumenta los valores de resistencia al cizallamiento del cemento de ionómero de vidrio modificado con resina con tecnología de nano relleno.


Subject(s)
Animals , Cattle , Composite Resins/chemistry , Shear Strength , Dentin/radiation effects , Temperature , In Vitro Techniques , Dental Cements , Dental Stress Analysis , Glass Ionomer Cements
8.
Int. j interdiscip. dent. (Print) ; 13(1): 17-20, abr. 2020. tab, graf
Article in English | LILACS | ID: biblio-1114887

ABSTRACT

STATEMENT OF THE PROBLEM: The literature still lacks evidence regarding which polishing techniques have the ideal clinical outcomes for bulk-fill resin composites. PURPOSE: This study evaluated the surface gloss of two commercially available bulk-fill resin composites after different polishing procedures and characterized their micromorphology via scanning electron microscopy. MATERIAL AND METHODS: 80 bulk-fill compactable composite resin discs were created. The control group was left untreated, and remaining samples were subjected to different polishing techniques. Gloss units were measured and surface morphology of disc samples was assessed. The Tukey post-hoc test was used to identify any differences. RESULTS: Statistically significant differences were found between the different polishing systems applied to Filtek BulkFill Posterior and Tetric N Bulk-Fill. No differences were found when the same polishing system was applied for both resins. The highest gloss values were obtained in the control group and the ENA Shiny system; the lowest were obtained with SofLex XT and Soflex Spiral Wheels for the bulk-fill composite resins studied. CONCLUSIONS. Diamond pastes have the highest gloss behavior, followed by diamond rubber points. The systems with aluminum oxide discs present the lower gloss behavior. SEM images provided useful evidence, and future studies should include an evaluation over time.


Subject(s)
Composite Resins/chemistry , Dental Polishing/methods , Surface Properties , Materials Testing
9.
Braz. oral res. (Online) ; 34: e035, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1100934

ABSTRACT

Abstract Although fiber-reinforced composites are commonly used in dental practice, whether fiber-reinforced crowns and fixed partial dentures can be used as definitive prostheses remains to be determined. This study used scanning electron microscopy to evaluate the load-bearing capacity of non-reinforced and fiber-reinforced composite (FRC) molar crowns prepared by computer-aided design/computer-aided manufacturing (CAD/CAM). The crowns were fabricated from three empirical FRC blocks, one empirical composite block, and one commercial ceramic block. The FRC resin was prepared by mixing BaO silicate particles, E-glass fiber, and dimethacrylate resin. Specimens were divided into five groups (n = 10), differing in the amounts of filler, resin, and fiber. Crowns were statically loaded until fracture. One-way analysis of variance and Tukey's post hoc multiple comparison tests were used for statistical analyses. The groups showed significant differences in load-bearing capacity; empirical bidirectional FRC resin blocks had the highest capacity, while commercial ceramic blocks had the lowest capacity. Molar crowns formed from FRC resin blocks had higher load-bearing capacity compared to non-reinforced composite resin and ceramic blocks. These results show that fiber reinforcement increased the load-bearing capacity of molar crowns.


Subject(s)
Humans , Weight-Bearing , Computer-Aided Design , Composite Resins/chemistry , Crowns , Reference Values , Surface Properties , Materials Testing , Microscopy, Electron, Scanning , Ceramics/chemistry , Reproducibility of Results , Dental Prosthesis Design , Evaluation Study , Molar
10.
J. appl. oral sci ; 28: e20190544, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1101250

ABSTRACT

Abstract Objective To evaluate the influence of three levels of dental structure loss on stress distribution and bite load in root canal-treated young molar teeth that were filled with bulk-fill resin composite, using finite element analysis (FEA) to predict clinical failure. Methodology Three first mandibular molars with extensive caries lesions were selected in teenager patients. The habitual occlusion bite force was measured using gnathodynamometer before and after endodontic/restoration procedures. The recorded bite forces were used as input for patient-specific FEA models, generated from cone-beam computed tomographic (CT) scans of the teeth before and after treatment. Loads were simulated using the contact loading of the antagonist molars selected based on the CT scans and clinical evaluation. Pre and post treatment bite forces (N) in the 3 patients were 30.1/136.6, 34.3/133.4, and 47.9/124.1. Results Bite force increased 260% (from 36.7±11.6 to 131.9±17.8 N) after endodontic and direct restoration. Before endodontic intervention, the stress concentration was located in coronal tooth structure; after rehabilitation, the stresses were located in root dentin, regardless of the level of tooth structure loss. The bite force used on molar teeth after pulp removal during endodontic treatment resulted in high stress concentrations in weakened tooth areas and at the furcation. Conclusion Extensive caries negatively affected the bite force. After pulp removal and endodontic treatment, stress and strain concentrations were higher in the weakened dental structure. Root canal treatment associated with direct resin composite restorative procedure could restore the stress-strain conditions in permanent young molar teeth.


Subject(s)
Humans , Child , Bite Force , Composite Resins/chemistry , Tooth, Nonvital/therapy , Dental Restoration, Permanent/methods , Molar , Reference Values , Tensile Strength , Reproducibility of Results , Treatment Outcome , Composite Resins/therapeutic use , Tooth, Nonvital/diagnostic imaging , Compressive Strength , Finite Element Analysis , Dental Stress Analysis , Cone-Beam Computed Tomography , Elastic Modulus , Patient-Specific Modeling
11.
Article in English | LILACS, BBO | ID: biblio-1135554

ABSTRACT

Abstract Objective: To evaluate the effect of a resin coating material on the microleakage of Class V composite resin restorations with and without post-operative bleaching. Material and Methods: Eighty class V cavities (3×3×1.5 mm) were prepared and filled with Z250 XT composite resin in the buccal and lingual surfaces of 40 sound human molars. Then the samples were randomly divided into 4 groups (n=20) and treated as follows: Group A: applying a resin coating (G-Coat Plus) on the restoration, then bleaching with 40% hydrogen peroxide; Group B: Post-Operative bleaching without prior use of resin coating; Group C: applying resin coating agent, and no further bleaching; and Group D: no resin coating, no bleaching. The specimens were thermocycled and immersed in 1% methylene blue for 24 hours, then cut into sections bucco-lingually. The samples were scored regarding the amount of dye penetration under a stereomicroscope (x20). Data were analyzed with Chi-squared and Fisher exact tests (p<0.05). Results: The maximum gingival and occlusal microleakage was detected in group B, while the minimum was seen in group C. In all the groups, microleakage at gingival margins was higher than occlusal margins (p<0.001). Conclusion: Application of a resin coating is an effective method in reducing microleakage of the restorations before and after bleaching.


Subject(s)
Humans , Male , Female , Composite Resins/chemistry , Dental Materials , Hydrogen Peroxide/chemistry , Molar , In Vitro Techniques/methods , Chi-Square Distribution , Statistics, Nonparametric , Iran/epidemiology
12.
Article in English | LILACS, BBO | ID: biblio-1135517

ABSTRACT

Abstract Objective: To evaluate the effect of pre-polymerization heating of nanocomposite filling materials on their strength properties within one manufacture group. Material and Methods: Two nanocomposite filling materials Enamel Plus HRi Universal Dentin® and Universal Enamel® were used. The linear thermal expansion coefficient (LTEC), Young's modulus and penetration depth were determined during the tests. Changes in the structure of materials were evaluated using electron scanning microscopy. Results: Dentin nanocomposite samples after pre-heating and polymerization have higher LTEC after 30°C compared to dentine nanocomposite untreated samples with statistically significance started at 62°C (p<0.05) and higher temperature. Pre-polymerization heated samples had a statistically higher LTEC (p<0.05) at 57°С. It was revealed that Young's modulus of the dentin nanocomposite samples after thermal processing at 55°C was higher in total after the first heating cycle by 15% compared to the untreated dentin nanocomposite samples (p<0.05). The volume of total porosity after pre-heating decreased to 5-7% (p<0.05). Conclusion: The material that has undergone preliminary heat processing is significantly less deformed under load than the material that does not have thermal processing during the research was established and also has a denser structure.


Subject(s)
Materials Testing , Composite Resins/chemistry , Dental Materials/chemistry , Nanocomposites , In Vitro Techniques/methods , Microscopy, Electron, Scanning , Analysis of Variance , Russia/epidemiology , Dental Enamel , Dentin
13.
Article in English | LILACS, BBO | ID: biblio-1135480

ABSTRACT

Abstract Objective: To evaluate the influence of cavosurface vestibular bevel (CSVB) application on the clinical success (CS) of class IV restorations of traumatized permanent teeth, the influence of the number of fracture angles and dental trauma recurrence (DTR) on the restorations retention rate (RRR) and incidence of pulp necrosis (PN). Material and Methods: Fifty-seven children and adolescents with enamel and dentin fractures requiring C-IV restorations were randomly allocated in groups with CSVB and without CSVB. The primary outcomes were the CS of restorations, evaluated using modified USPHS criteria, and the incidence of PN after a 6-months follow-up. As secondary outcomes, the influence of the number of fractured angles and the DTR on the RRR and on the incidence of PN were evaluated (p>0.05). Results: Of 57 children and adolescents, 74 teeth were restored, and 71 completed the six-month follow-up analysis. Teeth restored with and without CSVB displayed similar CS as well as the same incidence of PN (p>0.05). The number of fractured angles did not influence the RRR and DTR was not associated with PN (p>0.05). DTR was associated with a lower RRR (p<0.001). Conclusion: Cavosurface vestibular bevel did not influence the clinical success of Class IV restorations or incidence of PN after 6-months follow-up. DTR did not influence the incidence of pulp necrosis, but did negatively influence the restorations retention rate. The number of fracture angles did not influenced in the restorations retention rate.


Subject(s)
Humans , Male , Female , Child , Adolescent , Tooth Fractures/diagnostic imaging , Randomized Controlled Trial , Composite Resins/chemistry , Dental Restoration Failure , Dental Restoration, Permanent , Brazil/epidemiology , Chi-Square Distribution , Dental Pulp Necrosis , Dental Enamel
14.
Braz. oral res. (Online) ; 34: e005, 2020. tab, graf
Article in English | LILACS | ID: biblio-1055521

ABSTRACT

Abstract The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Subject(s)
Apatites/radiation effects , Radiation, Ionizing , Bisphenol A-Glycidyl Methacrylate/radiation effects , Composite Resins/radiation effects , Fluorides/chemistry , Glass Ionomer Cements/radiation effects , Apatites/chemistry , Reference Values , Spectrometry, X-Ray Emission , Surface Properties/radiation effects , Time Factors , Zirconium/radiation effects , Zirconium/chemistry , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Bisphenol A-Glycidyl Methacrylate/chemistry , Statistics, Nonparametric , Composite Resins/chemistry , Flexural Strength , Glass Ionomer Cements/chemistry
15.
Braz. oral res. (Online) ; 34: e001, 2020. tab, graf
Article in English | LILACS | ID: biblio-1055529

ABSTRACT

Abstract This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Subject(s)
Humans , Plant Oils/chemistry , Dental Bonding/methods , Dentin-Bonding Agents/chemistry , Dentin/drug effects , Fabaceae/chemistry , Surface Properties , Tensile Strength , Materials Testing , Chlorhexidine/chemistry , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Composite Resins/chemistry , Resin Cements/chemistry , Dental Cements/chemistry , Dental Leakage , Dentin/chemistry , Emulsions/chemistry
16.
Braz. oral res. (Online) ; 34: e045, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132712

ABSTRACT

Abstract This in vitro study aimed to evaluate the effect of a silane-containing universal adhesive used with or without a silane agent on the repair bond strength between aged and new composites. Forty nanohybrid composite resin blocks were stored in distilled water for 14 d and thermo-cycled. Sandpaper ground, etched, and rinsed speciments were randomly assigned into four experimental groups: silane + two-step etch-and-rinse adhesive system, two-step etch-and-rinse adhesive system, silane + silane-containing universal adhesive system, and silane-containing universal adhesive system. Blocks were repaired using the same composite. After 24 h of water storage, the blocks were sectioned and bonded sticks were submitted to microtensile testing. Ten unaged, non-repaired composite blocks were used as a reference group to evaluate the cohesive strength of the composite. Two-way ANOVA and Tukey's tests were used to analyze average µTBS. One-way ANOVA and Dunnet post-hoc tests were used to compare the cohesive strength values and bond strength obtained in the repaired groups (α = 0.05). The µTBS values were higher for the silane-containing universal adhesive compared to the two-step etch-and-rinse adhesive system (p = 0.002). Silane application improved the repair bond strength (p = 0.03). The repair bond strength ranged from 39.3 to 65.8% of the cohesive strength of the reference group. Using universal silane-containing adhesive improved the repair bond strength of composite resin compared to two-step etch-and-rinse adhesive. However, it still required prior application of a silane agent for best direct composite resin repair outcomes.


Subject(s)
Silanes/chemistry , Composite Resins/chemistry , Resin Cements/chemistry , Dental Cements/chemistry , Reference Values , Surface Properties , Tensile Strength , Time Factors , Materials Testing , Reproducibility of Results , Analysis of Variance , Dental Bonding/methods
17.
Braz. oral res. (Online) ; 34: e001, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089393

ABSTRACT

Abstract This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Subject(s)
Humans , Plant Oils/chemistry , Dental Bonding/methods , Dentin-Bonding Agents/chemistry , Dentin/drug effects , Fabaceae/chemistry , Surface Properties , Tensile Strength , Materials Testing , Chlorhexidine/chemistry , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Composite Resins/chemistry , Resin Cements/chemistry , Dental Cements/chemistry , Dental Leakage , Dentin/chemistry , Emulsions/chemistry
18.
J. appl. oral sci ; 28: e20190042, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1056592

ABSTRACT

Abstract Gap formation of composite resin restorations is a serious shortcoming in clinical practice. Polymerization shrinkage stress exceeds the tooth-restoration bond strength, and it causes bacterial infiltration within gaps between cavity walls and the restorative material. Thus, an intermediate liner application with a low elastic modulus has been advised to minimize polymerization shrinkage as well as gap formation. Objective: The purpose of this in vitro study was to assess gap formation volume in premolars restored with different bulk-fill composites, with and without a resin-modified glass-ionomer cement (RMGIC) liner, using x-ray micro-computed tomography (micro-CT). Methodology: Sixty extracted human maxillary premolars were divided into six groups according to bucco-palatal dimensions (n=10). Standardized Class II mesio-occluso-distal cavities were prepared. G-Premio Bond (GC Corp., Japan) was applied in the selective-etch mode. Teeth were restored with high-viscosity (Filtek Bulk Fill, 3M ESPE, USA)-FB, sonic-activated (SonicFill 2, Kerr, USA)-SF and low viscosity (Estelite Bulk Fill Flow, Tokuyama, Japan)-EB bulk-fill composites, with and without a liner (Ionoseal, Voco GmbH, Germany)-L. The specimens were subjected to 10,000 thermocycles (5-55°C) and 50,000 simulated chewing cycles (100 N). Gap formation based on the volume of black spaces at the tooth-restoration interface was quantified in mm3 using micro-computed tomography (SkyScan, Belgium), and analyses were performed. Data were analyzed using repeated-measures ANOVA and the Bonferroni correction test (p < 0.05). Results: The gap volume of all tested bulk-fill composites demonstrated that Group SF (1.581±0.773) had significantly higher values than Group EB (0.717±0.679). Regarding the use of a liner, a significant reduction in gap formation volume was observed only in Group SFL (0.927±0.630) compared with Group SF (1.581±0.773). Conclusion: It can be concluded that different types of bulk-fill composite resins affected gap formation volume. Low-viscosity bulk-fill composites exhibited better adaptation to cavity walls and less gap formation than did sonic-activated bulk-fill composites. The use of an RMGIC liner produced a significant reduction in gap formation volume for sonic-activated bulk-fill composites.


Subject(s)
Humans , Composite Resins/chemistry , Imaging, Three-Dimensional/methods , Dental Cavity Preparation/methods , Dental Materials/chemistry , Dental Restoration, Permanent/methods , Polymerization , In Vitro Techniques , Materials Testing , Resin Cements , Dental Stress Analysis , X-Ray Microtomography
19.
São José dos Campos; s.n; 2020. 42 p. il., graf., tab..
Thesis in Portuguese | LILACS, BBO | ID: biblio-1146886

ABSTRACT

O presente trabalho teve como objetivos: (1) analisar, in silico, o efeito de diferentes técnicas restauradoras sobre a concentração de tensão em lesões cervicais não cariosas (LCNCs); (2) avaliar in silico e in vitro a influência do ângulo cavo-superficial sobre a concentração de tensão em LCNCs simuladas; (3) avaliar, in silico e in vitro, a influência da extensão da cavidade e do material restaurador na formação de fendas marginais, e na concentração de tensão em restaurações de resina composta; (4) avaliar, in vivo, a influência da geometria de LCNCs e material restaurador no desempenho clínico das restaurações e (5) analisar, por revisão sistemática e metanálise, a influência dos aspectos relacionados ao dente e cavidade de LCNCs sobre a retenção de restaurações de resina composta. Material e métodos: (1) Um pré-molar superior foi modelado em software CAD, e uma LCNC do tipo cunha foi simulada. Cinco técnicas restauradoras foram reproduzidas com as resinas Filtek™ Z350 XT (N) ou Filtek™ Bulk Fill (BF) e analisadas pelo software Ansys 17.0; (2) Cavidades cilíndricas com mesmo volume (17,67 mm³) foram preparadas em 45 incisivos bovinos. As amostras foram divididas de acordo com o ângulo cavo-superficial, em três grupos: 90º, 120º, 135º, e restauradas com o adesivo Futurabond U e resina GrandioSO. As fendas marginais foram medidas em estereomicroscópio, e análise por elementos finitos (FEA); (3) Cavidades simulando LCNCs com 2 mm (profundidade) C 4 mm (distância cérvico-incisal) foram preparadas em 60 incisivos bovinos em duas dimensões mésio-distais (2,9 mm ou 1,4 mm) e restauradas com N ou BF (n=30). A fenda marginal foi avaliada em estereomicroscópio antes e após da termociclagem, e realizada análise por FEA em cavidades iguais; (4) Cento e quarenta LCNCs foram restauradas em 77 pacientes. As lesões foram previamente classificadas quanto à extensão gengivooclusal (1,5 mm ± 10% e 3 mm ± 10%). Em seguida, as lesões foram alocadas aleatoriamente em quatro grupos (n=35). Após a aplicação de um adesivo autocondicionante, as restaurações foram realizadas com N ou BF. As restaurações foram avaliadas após 7 dias, 6 e 12 meses pelos critérios USPHS modificados; (5) Buscas nas principais bases de dados eletrônicas foram realizadas. Estudos clínicos em pacientes com LCNCs restauradas com resina composta foram incluídos. A retenção da restauração foi o desfecho primário. A qualidade metodológica e risco de viés dos artigos incluídos foi avaliada utilizando a ferramenta Cochrane para ensaios clínicos randomizados e o sistema GRADE. Resultados: (1) A menor concentração de tensão ocorreu no grupo restaurado com resina BF; (2) O ângulo cavo-superficial de 90º promoveu maiores tensões na interface da restauração, com maior fenda marginal; (3) Ocorreu maior concentração de tensão na margem do esmalte, com maior pico de tensão (17,0 MPa) para cavidade pequena restaurada com resina N; (4) A taxa de retenção das restaurações após 12 meses foi de 100% para as LCNCs restauradas com N e de 97% para as LCNCs restauradas com BF; (5) A localização do dente e a presença de facetas de desgaste podem afetar a retenção de resinas compostas em LCNCs(AU)


The aim of the present study was (1) to analyze in silico the effect of different restorative techniques on the stress concentration in non-carious cervical lesions (NCCLs);(2) to evaluate in silico and in vitro the influence of cavosurface margin angle on stress concentration in simulated NCCLs; (3) to evaluate in silico and in vitro the influence of cavity extension and restorative material on the marginal gap formation, and on the stress concentration in resin restoration; (4) to evaluate in vivo the influence of the geometry of NCCLs and restorative material on the clinical performance of restoration and (5) to analyze, through a systematic review and meta-analysis, the influence of tooth- and cavity-related of NCCLs on the retention of resin composite restorations. Materials and Methods: (1) A superior premolar was modeled in CAD software, and a NCCLs of the wedge type was simulated. Five restorative techniques were designed with Filtek™ Z350 XT (N) or Filtek™ Bulk Fill (BF) and analyzed by Ansys 17.0 software; (2) Cylindrical cavities with the same volume (17.67 mm³) were prepared in 45 bovine incisors. The samples were divided according to the cavo-superficial angle in three groups: 90º, 120º, 135º, and restored with Futurabond U adhesive and GrandioSO resin. The marginal gaps were analyzed in stereomicroscope and FEA; (3) Cavities simulating NCCLs with 2 mm (depth) C 4 mm (cervical-incisal distance) were prepared in 60 bovine incisors in two mesiodistal dimensions (2.9 mm or 1.4 mm) and restored with N or BF (n=30. The marginal gap was evaluated using a stereomicroscope before and after thermocycling, and FEA analysis was performed in equal cavities; (4) One hundred and forty NCCLs were restored in 77 patients. The lesions were previously classified for occlusogingival distance (1.5 mm ± 10% and 3 mm ± 10%). Thereafter, the lesions were randomly allocated into four groups (n=35). After applying a self-etching adhesive, the restorations were performed using N or BF. The restorations were evaluated after 7 days, 6 and 12 months using the modified USPHS criteria; (5) Searches in major electronic databases were performed. Clinical studies in patients with NCCLs restored with resin composite were included. Restoration retention was the primary outcome. The quality of the evidence and risk of bias of the included articles was evaluated using the Cochrane tool for randomized clinical trials and the GRADE. Results: (1) The lowest concentration of stress occurred in the group restored with BF resin; (2) The cavosuperficial angle of 90º promoted higher stresses at the interface of the restoration, with a larger marginal gap; (3) Higher stress concentration occurred at the enamel margin, with highest stress peak (17.0 MPa) for small cavity restored with N; (4) The retention rate of the restorations after 12 months was 100% for the NCCLs restored with N and 97% for the NCCLs restored with BF; (5) The tooth location and the presence of wear facets can affect the retention of composite resins in NCCLs(AU)


Subject(s)
Randomized Controlled Trial , Meta-Analysis , Composite Resins/chemistry , Finite Element Analysis/classification , Tooth Wear/complications
20.
Acta odontol. latinoam ; 32(3): 126-132, Dec. 2019. graf
Article in English | LILACS | ID: biblio-1130718

ABSTRACT

ABSTRACT The aim of this study was to evaluate the effect of flowable composite or glass ionomer liners on the shrinkage stress of a restorative composite resin. Fifteen previously sandblasted metal boxes were attached to a universal mechanical testing machine (INSTRON 1011, Instron Corporation). Five of these boxes were filled with Filtek Z350 XT (FXT) Universal Restorative A2 (3M ESPE) (Group 1 or Control). Two further groups of 5 boxes were prepared by interposing a layer of Vitrebond Light Cure Glass Ionomer 3M ESPE (VGI) (Group 2 or G.I.) or Filtek Z350 XT Flowable Restorative A2 3M ESPE (FFR) (Group 3 or Flowable) between the box and the composite resin, completing with the same volume of composite as in Group 1. Upon activating lightcuring, the filled boxes mounted on the testing machine were videoed for 60 seconds (40 s photoactivation and 20 s postcuring), timed with a digital chronometer. Force values were recorded in newtons and converted into stress according to contact surface. Stress values were recorded every 10 s. Results were analyzed using repeated measures ANOVA. Mean and standard deviation in kPa (stress) recorded for each group were: Control group: 126.2 (30.8); G.I.: 48.4 (18); Flowable: 27.9 (19.5). Statistical analysis showed significant differences between the control group and the rest (p<0.01), with no significant difference between groups with glass ionomer liners and flowable resin liners (G.I. and Flowable). Under the experimental conditions of this study, it can be concluded that polymerization shrinkage stress can be reduced by the presence of a liner between the preparation and the restorative material.


RESUMEN El objetivo de este trabajo fue evaluar el efecto de la colocación de una capa de Composite flow o Ionómero vítreo sobre la tensión de contracción de un composite para restauración. Se utilizaron 15 cajas metálicas previamente arenadas y conectadas a la máquina universal para ensayos mecánicos (INSTRON 1011, Instron Corporation). Cinco de estas cajas (G1) se rellenaron con Filtek Z350 XT (FXT) Universal Restorative A2 3M ESPE. Al iniciar la activación de la unidad de curado se comenzaba a registrar con una cámara de video y un cronómetro digital desde el comienzo de la activación de la lámpara hasta 60 s después, registrando los valores post curado durante 20 s. Los valores de fuerza generados por la polimerización fueron registrados en newton de cada 10 s para los 15 ensayos. Los valores fueron convertidos en tensión de contracción según la superficie de contacto. Se realizaron además dos grupos de cajas (5 en cada una) en los cuales se colocaron una capa inicial de Vitrebond Light Cure Glass Ionomer 3M ESPE (VGI) (G2 o IV) y Filtek Z350 XT Flowable Restorative A2 3M ESPE (FFR) (G3 o Flow) y se completó con el mismo volumen de composite de las del GI. Los resultados obtenidos fueron analizados por medio de ANOVA para mediciones repetidas. La media y la desviación estándar en kPa (tensión o estrés de contracción) registrado para cada grupo fueron: Grupo control: 126.2 (30.8); IV: 48.4(18); Flow: 27.9(19.5). El análisis estadístico mostró diferencias estadística mente significativas entre el grupo control y el resto (p=0.00), pero no hubo diferencias significativas entre la presencia de Ionómero vítreo o Composite Flow (IV y Flow). En las condiciones experimentales de este trabajo puede concluirse que la tensión de contracción generada durante la polimerización puede ser disminuida por la presencia de algún material interpuesto entre la preparación y el composite restaurador.


Subject(s)
Acrylic Resins , Silicon Dioxide , Composite Resins/chemistry , Dental Leakage , Dental Materials/chemistry , Dental Restoration, Permanent , Materials Testing , Dental Cavity Lining/methods , Dental Cavity Preparation , Polymerization , Glass Ionomer Cements/chemistry
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