Within the last 25 years composite resin materials have in many countries successively replaced amalgam as a restorative for posterior teeth. Resin materials and bonding systems are continuously being improved by the manufactures, adhesive procedures are now included in the curriculum of most universities and practicing dentists restore millions of teeth throughout the World with composite resin materials. Do we know enough about the clinical performance of these restorations over time?
Numerous in vitro studies are being published on resin materials and adhesion, some of them attempting to imitate in vivo conditions. But real life is different and in vitro studies cannot include all variables. Only clinical studies can provide valid information on the clinical performance of restorations over time.
What do we know about longevity of posterior resin restorations? What are the reasons for replacement and repair? Have new materials improved longevity? Are there still clinical and material problems to be solved? And what has the highest impact on longevity of posterior resin restorations – the material, the dentist, the patient or the tooth?
These matters will be discussed on the basis of the literature and results from own up to 30-year prospective clinical university studies and practice based studies from Public Dental Health Service on the clinical performance of posterior composite resin restorations.