Managing the polymerization shrinkage of resin composite restorations: a review (original) (raw)
Related papers
2020
Citation: Nagy Abdulsamee., et al. “Shrinkage of Dental Composite Resin: Contemporary Understanding its Enigmas and How to Solve? A Review”. EC Dental Science 19.5 (2020): 03-17. Abstract Nowadays dental patients are seeking a restorative material to their teeth that fulfilled most of the ideal requirements for such use especially aesthetic and functional performance needs. Traditionally composite resin can fulfill these requirements but with the major drawback of shrinkage during polymerization. The shrinkage will be manifested as marginal leakage, cuspal deflection, tooth or restoration fracture, postoperative sensitivity that ends ultimately by failed restoration. The aim of the current work was to pay attention of dental workers to the origin of polymerization shrinkage, its consequences, factors affecting, methods used to measure it, and how can they minimize it for promoting longevity of the restoration.
Polymerization shrinkage of composite resins: consequences and control
Bonding strategies associated with the aesthetic and conservative properties of resin materials have increased their popularity in restorative dentistry. Direct composite restorations are one of the most prevalent medical interventions on the human body, with millions of composite restorations placed each year around the world. The optimal performance of these restorations depends on the proper polymerization of the resin component, which is characterized by the transformation of monomers into polymers, accompanied by volumetric reduction of the material. Despite several improvements in new restorative materials in recent years, the disadvantages related to polymerization shrinkage of resin composites remain a clinical problem. The aim of this study is to explore, through an integrative literature review, the causes of polymerization shrinkage of composite resins, as well as their risks and how to control them, in order to obtain long-lasting restorations. A consequence of shrinkage stress can be related to the detachment along the restoration/tooth interface or restoration margins, resulting in internal and marginal gaps, microcracks of one or both restorative material and tooth structure, marginal stain, and cusp deflection. Clinical Relevance-Clinicians must understand the concept of polymerization shrinkage stress and realize that the quality of composite resin restorations depends on the successful management of these efforts.
Dental Materials, 2005
Objectives. Polymerization shrinkage stress of resin-composite materials may have a negative impact on the clinical performance of bonded restorations. The purpose of this systematic review is to discuss the primary factors involved with polymerization shrinkage stress development. Data. According to the current literature, polymerization stress of resin composites is determined by their volumetric shrinkage, viscoelastic behavior and by restrictions imposed to polymerization shrinkage. Therefore, the material's composition, its degree of conversion and reaction kinetics become aspects of interest, together with the confinement and compliance of the cavity preparation. Sources. Information provided in this review was based on original scientific research published in Dental, Chemistry and Biomaterials journals. Textbooks on Chemistry and Dental Materials were also referenced for basic concepts. Conclusions. Shrinkage stress development must be considered a multi-factorial phenomenon. Therefore, accessing the specific contribution of volumetric shrinkage, viscoelastic behavior, reaction kinetics and local conditions on stress magnitude seems impractical. Some of the restorative techniques aiming at stress reduction have limited applicability, because their efficiency varies depending upon the materials employed. Due to an intense research activity over the years, the understanding of this matter has increased remarkably, leading to the development of new restorative techniques and materials that may help minimize this problem.
Polymerization Shrinkage of Composite Resins: A Review
The greatest limitation in the use of composite resins as a posterior restorative material seems to be shrinkage during polymerization, which often leads to marginal fracture , subsequent secondary caries , marginal staining , restoration displacement , tooth fracture and, or post operative sensitivity . The objectives of this article are to throw light on the origin of polymerization shrinkage, the clinical factors affecting polymerization stress, and methods advocated to reduce shrinkage stress and the effectiveness of these methods.
Dental Materials, 2019
Objective. Resin-based composites are widely used in dental restorations; however, their volumetric shrinkage during polymerization leads to several issues that reduce the restoration survival rates. For overcoming this problem, a deep study of shrinkage phenomena is necessary. Methods. In this study, micro-tomography (-CT) is combined with digital volume correlation (DVC) to investigate the effect of several factors on the polymerization strain of dental composites in model cavities: the presence/absence of an adhesive, the use of transparent/blackened cavities, and irradiation times between 1 and 40 s. Results. The results indicate that the presence of an adhesive at the interface between the cavity and composite does not reduce the total strain but instead limits it to a preferential direction. In addition, regardless of the conditions, the main strain is generated along the axis parallel to the polymerization irradiation (the vertical axis). Finally, the total strain appears to occur in the first 5 s of irradiation, with no further evolution observed for longer irradiation times. Significance. This work provides new insight into resin-based composite shrinkage and demonstrates the benefit of coupling DVC and-CT to better understand the degradation mechanisms of these materials.
Shrinkage Stresses Generated during Resin-Composite Applications: A Review
Journal of dental biomechanics, 2010
Many developments have been made in the field of resin composites for dental applications. However, the manifestation of shrinkage due to the polymerization process continues to be a major problem. The material's shrinkage, associated with dynamic development of elastic modulus, creates stresses within the material and its interface with the tooth structure. As a consequence, marginal failure and subsequent secondary caries, marginal staining, restoration displacement, tooth fracture, and/or post-operative sensitivity are clinical drawbacks of resin-composite applications. The aim of the current paper is to present an overview about the shrinkage stresses created during resin-composite applications, consequences, and advances. The paper is based on results of many researches that are available in the literature.
The journal of adhesive dentistry, 2013
To investigate how the incremental filling technique, elastic modulus, and post-gel shrinkage of different dental composite resins affect residual shrinkage stress in a restored premolar. Sixteen composites indicated for restoring posterior teeth were tested. Elastic modulus and Knoop hardness were measured using Knoop indentation tests (n = 10). A strain gauge test was used to measure the post-gel shrinkage (n = 10). Two incremental techniques, horizontal or oblique, were applied in a finite element model of a premolar in combination with the experimentally determined properties to assess the stress conditions along the interface of the restoration and within the material structures. Linear regressions were determined between residual shrinkage stress and the elastic modulus and post-gel shrinkage values. The mechanical properties and the post-gel shrinkage varied significantly among the composites tested. The calculated shrinkage stress showed a strong correlation with post-gel sh...
Assessment of polymerization shrinkage of different bulk-fill resin composites
Al-Azhar Journal of Dental Science, 2021
Objectives: This research was designed to evaluate the effect of polymerization shrinkage of different bulk-fill resin composites. Materials & Methods: Ninety extracted molars were prepared as specimens by having a box shape proximal cavity for restoration of composite resins. The specimens were divided for three main groups (n=30), according to the resin composite materials used (sonic fill, flowable and packable bulk fill). Profile projector was used for assessment of polymerization shrinkage. Results: There is no significant difference of variables. Sonic fill composite resin has lower polymerization shrinkage than flowable bulk fill composite and packable bulk fill composite. Conclusions: success of composite depends mainly on the material polymerization shrinkage as when the shrinkage decrease mostly the postoperative problems decrease.