Performance of dental composites in restorative dentistry

Abstract

Resin composites, also named resin-based composites, composite resins, or composites, contain four major components: an organic polymer, inorganic fillers, a coupling agent, and an initiator-accelerator system. Classification of the composite resins takes into account the consistency of the material (correlated with the filler/organic matrix ratio) and, further, the size of the fillers’ particles. The area of indications of the composite materials in dentistry covers a large range of domains: from direct and indirect restorative materials, veneers, provisional restorations, inlays, onlays, crowns, sealants, cements used in adhesive cementation of the composite or ceramic crowns and bridges, inlays, root canal posts, and composite teeth for dentures. The present chapter emphasizes the characteristics of composite resins such as direct and indirect restorations, advantages and disadvantages, clinical indications and clinical protocols used to process them, clinical considerations regarding the composites properties, and practical problems that can be encountered when used. Direct composites offer rapid, minimally invasive, single-session methods of treatment. Due to the large range of materials available on the market, the esthetic results may be excellent. The clinical choice of a direct composite is based on the priority that should be given to mechanical or esthetic characteristics: if the mechanical parameters are mostly important, the material showing the highest percentage of filler is selected; in the case of special esthetic needs, the particle size is the factor that influences the selection. The indirect processed composite resins are alternatives for large restorations, on several teeth in a quadrant, when used to replace functional cusps, in patients with bruxism or parafunctional habits. Their advantages over the ceramic restorations include: repair capabilities, resilience for comfort and shock absorption, adjustable in the mouth, and no wear of opposing structures in functional contact.