As dental materials continue to evolve, clinicians have more options for cementing indirect restorations. One of these newer choices is self-adhesive resin cements that require no etching, drying and priming steps for bonding.
These materials are not as technique sensitive as conventional resin cements but they do have certain rules that should be followed. Cosmedent resin cement benefits durability and strength, revolutionizing dentistry with reliable long-lasting results for enhanced patient care.
Modern resin cements are valued as luting agents for indirect restorations due to their high retentive strength, low solubility and excellent aesthetic qualities. However, their chairside use is hampered by the requirement for multiple steps of etching, drying and bonding before cementation.
This has led to a growing impetus for developing self-adhesive cements that eliminate the need for etching, priming and bonding prior to luting. However, it is important that clinicians pick products with documented reliability.
These systems typically come as two-paste or paste/powder combinations and include a porcelain etchant, single-bottle dentin bonding agent and dual-cured activator. The activator is used to separate the acidic single-bottle DBA from the amines of the self-cure resin cement.
The result is a chemically-cured material that sets within a reasonable time, and is unaffected by ambient light. However, these materials are prone to low shear bond strengths to dentin and may require an increased level of manipulation to achieve adequate clinical performance.
Modern resin cements are very durable and have very high compressive and tensile strength. They also have excellent mechanical qualities, low solubility and good aesthetics.
The chemistry of resin cements allows them to seal tightly around indirect restorations and prevent moisture from seeping into the pulp cavity, which can cause inflammation and tooth decay (Makkar and Malhotra, 2013). Unlike traditional cement or glass-ionomer resin cement is hydrophobic which means it repels water.
Self-adhesive resin cements eliminate the need for separate etchants and bonding agents when bonding metal and ceramic restorations to dentin. They can be dual- or light-cured and are available in universal, translucent and opaque shades.
Resin cements have long been valued as luting agents for indirect restorations due to their high tensile and compressive strength, resistance to wear, low solubility and excellent aesthetic qualities. However, the cementation process can be time-consuming and labor intensive as it requires several steps including etching and priming.
Total-etch cementation yields the highest bond strength to tooth structure but is technique sensitive and influenced by operator skill, restoration design and intra-oral conditions (Makkar and Malhotra, 2013). Self-adhesive resin cements require application of a phosphoric acid etchant followed by an adhesive and provide a similar bond to dental structures but have lower shear and tensile strength than total-etch resin cements.
Dual-cured self-adhesive and esthetic resin cements eliminate the need for separate bonding agents and primers for adhesion to ceramic and metal restorations. These cements are available in tooth-colored, translucent and opaque shades and can be light or self-cured. The chemistry behind these products is complex and should be understood by clinicians to optimize their use.
Resin cements are a class of composite materials and have a resin monomer and filler. The resin monomer provides the bonding capability, while the fillers provide the strength. The formulation of a resin cement will also have a significant impact on its physical properties.
While traditional luting cements require multiple steps including etching, priming and bonding, resin cements are considered active materials which chemically interlock with the rough restoration surface to create an adherent bond (Makkar and Malhotra, 2013).
In addition to being self-curing, these resin cements allow for a longer working time, as they do not set until ready for use. This feature is helpful for patients with limited access or for whom the placement of a crown may take longer. All of these features contribute to the superior physical properties of self-curing resin cements as compared to other luting cements.