Problems of Direct Composite Posterior Restorations: A Clinical Study

In recent years, the increasing demand for aesthetically appealing, naturally-coloured dental restoration options has given rise to a growth in the use of composites in the posterior dental area [1-5]. The declining acceptance of dental amalgam and the mercury problem also makes an alternative to amalgam necessary [6,7]. In a statement from the German Scientific Association for Operative Dentistry and European Federation of Conservative Dentistry, it is defined, that indications for the use of direct composite systems may vary according to specific circumstances [8]. Three different indications are named in this statement, including restorations of tooth structure and contour, shape changing restorations and combinations of these possibilities [8]. However it remains clear, that restorations in the posterior area, which are subject to high mechanical stresses, should always be performed using materials with high strength and good radiopacity properties. Many authors of comparable long-term studies referred to the use of hybrid composites, as only such materials demonstrated both superior restoration margin stability and much better physical properties, including adequate abrasion resistance and flexural strength, which maked them suitable replacements for amalgam [1,9-11]. To meet the requirements of good long-term clinical and aesthetically appealing therapy results using a composite filling, it is also essential to consistently adhere to processing parameters. Even the smallest deviations from the application recommendations can cause clinical failures [7,12-14].