Sammanfattning
Restorative dental treatment still lays claim to a large proportion of dentists' working day. After
the phase-out of amalgam as a restorative material, composite resin has become the dominating
material of choice among dentists. The development of both restorative materials and techniques aim
to improve treatment outcomes. At present, there is a wide variety of resin composite materials on
the market and the development of new products is rapid. The ability to predict results in the clinic
based on only in vitro studies, is however limited. It is therefore necessary to perform clinical trials
that test the restorative materials under realistic conditions. Clinical trials of restoration longevity
include randomized controlled trials (RCTs), retrospective cross-sectional studies and practice-based
studies, which all have different strengths and weaknesses. Some few systematic reviews have
compared and evaluated clinical studies on restoration longevity. Secondary caries and fractures are
considered to be the most common reasons for replacement of resin composite fillings. Since the
development of secondary caries and other restoration failures takes some time, it is crucial that
clinical studies have long observation times to be able to provide a reliable result. Resin composites
are today considered to have comparable longevity with amalgam, presenting annual failure rates
(AFRs) of 1 - 3 %. Four main factors seem to influence restoration longevity; the material, the method,
the operator and the patient. Today's resin composites are generally of good quality, so the longevity
of a restoration is above all dependent on factors related to the patient and operator.