Composite resins and bonded porcelain: the postamalgam era?

The growing demand of patients for esthetic or metal-free restorations, together with the ongoing interest of the dental profession for tissue-preserving materials have led to the actual development of posterior adhesive restorations. It is now clearly established that a new biomimetic approach to restorative dentistry is possible through the structured use of "tooth-like" restorative materials (composite resins and porcelain) and the generation of a hard tissue bond (enamel and dentin bonding). Scientific studies and clinical experience have validated use of bonded tooth-colored restorations, and we may have entered the so-called "postamalgam era". These significant changes have already impacted daily general practice, including pediatric dentists in California, but it is now critical to assure that the corresponding evidence-based process is integrated to the predoctoral programs statewide and nationwide. This paper reviews the foundations of this evolution, based on maximum tissue preservation and sound biomechanics, the so-called "biomimetic principle". Using scientific evidence and clinical experience, a model for the adequate use of current restorative systems is presented. This work, illustrated with cases with up to 10 and 14 years' follow-up, sets the ground rules for the clinical performance of the posterior esthetic restoration. Important considerations about tooth preparation, matrix techniques, layering methods, immediate dentin sealing and base lining are presented.