RESUMO

Resin composites are the most versatile restorative materials used in dentistry and the first choice for restoring posterior teeth. This article reviews aspects that influence the clinical performance of composite restorations and addresses clinically relevant issues regarding different direct techniques for restoring posterior teeth that could be performed in varied clinical situations. The article discusses the results of long-term clinical trials with resin composites and the materials available in the market for posterior restorations. The importance of photoactivation is presented, including aspects concerning the improvement of the efficiency of light-curing procedures. With regard to the restorative techniques, the article addresses key elements and occlusion levels for restoring Class I and Class II cavities, in addition to restorative strategies using different shades/opacities of resin composites in incremental techniques, restorations using bulk-fill composites, and shade-matching composites.

RESUMO

RESUMEN: Introducción: Las restauraciones en el sector posterior son generalmente manejadas mediante el uso de resinas convencionales con técnica incremental. Debido a diversas limitaciones de la técnica convencional, la técnica bulk-fill ha ganado relevancia en la práctica clínica. Este resumen tiene como objetivo evaluar la efectividad de ambas técnicas al momento de realizar restauraciones clase I y clase II de Black en dientes posteriores permanentes. Métodos: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Resultados y conclusiones: Identificamos cinco revisiones sistemáticas que en conjunto incluyeron 15 estudios primarios, todos correspondientes a ensayos aleatorizados. Concluimos que la técnica bulk-fill podría aumentar levemente el fracaso de la restauración a mediano plazo, podría resultar en poca o nula diferencia en el fracaso de la restauración a largo plazo y podría resultar en poca o nula diferencia en el desarrollo de caries secundaria, pero la certeza de la evidencia es baja. La técnica bulk-fill probablemente resulta en poca o nula diferencia en el riesgo de sensibilidad postoperatoria.

ABSTRACT: Introduction: Conventional resin composite has been widely used in the restoration of posterior teeth. However, due to its limitations, the bulk-fill technique has been adopted by clinicians. This evidence summary aims to evaluate the effectiveness of both techniques for class I and II restorations in permanent posterior teeth. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified five systematic reviews including fifteen studies overall, of which all were randomized trials. We conclude that bulk-fill technique may slightly improve the risk of medium-term restoration failure, may make little or no difference to long-term restoration failure and may make little or no difference to secondary caries but the certainty of the evidence has been assessed as low. Finally, bulk-fill technique probably makes little or no difference to postoperative sensibility.

Assuntos

RESUMO

OBJECTIVE: This study evaluated the effect of different restorative techniques for non-carious cervical lesions (NCCL) on polymerization shrinkage stress of resins using three-dimensional (3D) finite element analysis (FEA). METHODS: 3D-models of a maxillary premolar with a NCCL restored with different filling techniques (bulk filling and incremental) were generated to be compared by nonlinear FEA. The bulk filling technique was used for groups B (NCCL restored with Filtek™ Bulk Fill) and C (Filtek™ Z350 XT). The incremental technique was subdivided according to mode of application: P (2 parallel increments of the Filtek™ Z350 XT), OI (2 oblique increments of the Filtek™ Z350 XT, with incisal first), OIV (2 oblique increments of the Filtek™ Z350 XT, with incisal first and increments with the same volume), OG (2 oblique increments of the Filtek™ Z350 XT, with gingival first) and OGV (2 oblique increments of the Filtek™ Z350 XT, with gingival first and increments with the same volume), resulting in 7 models. All materials were considered isotropic, elastic and linear. The results were expressed in maximum principal stress (MPS). RESULTS: The tension stress distribution was influenced by the restorative technique. The lowest stress concentration occurred in group B followed by OG, OGV, OI, OIV, P and C; the incisal interface was more affected than the gingival. CONCLUSION: The restoration of NCCLs with bulk fill composite resulted in lower shrinkage stress in the gingival and incisal areas, followed by incremental techniques with the initial increment placed on the gingival wall. CLINICAL SIGNIFICANCE: The non-carious cervical lesions (NCCLs) restored with bulk fill composite have a more favorable biomechanical behavior.

Assuntos

RESUMO

AIM: The aim of this study was to compare the restorative time required and the internal adaptation after thermomechanical aging of class I restorations using either the conventional incremental technique or bulk-fill technique. MATERIALS AND METHODS: Cavities (Class I) were prepared on the occlusal surface of human third molars. 40 teeth were divided into four experimental groups according to the restorative technique (n = 10): G1 = 3 mm increment of Surefill SDR Flow + 1 mm Filtek P60; G2 = 3 mm increment of Filtek Bulk-Fill + 1 mm Filtek P60; G3 = Filtek P60 inserted with incremental technique; G4 = 3 mm increment of Filtek Z350 Flow XT + 1 mm increment of Filtek P60. The required restorative clinical time for each technique was marked. Specimens were submitted to thermomechanical loading (20,000 mechanical cycles-80 N/thermal cycling-5/55°C for 30 seconds). After, samples were sectioned, ratio of internal gaps to interface length (%) was recorded using dye-staining-gap technique. Data were submitted to analysis of variance (ANOVA) and Tukey's test (95% significance). RESULTS: There was no significant difference in gap formation and none of the groups was completely gap-free. However, a significant reduction on required restorative clinical time was observed for G1 (167 ± 7 seconds), G2 (169 ± 4 seconds), and G4 (169 ± 8 seconds) when compared with G3 (204 ± 8 seconds). CONCLUSION: No significant difference in gap formation was found among bulk-fill and conventional incremental restorative technique tested; however, the use of a bulk-fill composite reduced 20% of the required restorative clinical time. CLINICAL SIGNIFICANCE: None of the restorative techniques applied were able to prevent internal gap formation. The use of bulk-fill composite reduced the required clinical time to perform class I restorations.

Assuntos