The Sir John Walsh Research Institute Research Day 2019 - Keynote presentation Posterior composite restorations - friend or foe?

摘要

While there is no question about the use of tooth-colored resin-based materials in the anterior segment, there exist still some doubts about their use in load-bearing areas, especially with larger cavities. In Switzerland, amalgam has been almost completely replaced by composite resin materials for almost 30 years and the so-called "Swiss Quality Guidelines" have been established and published to define distinct parameters for success and failure. The minimal longevity, which should be achieved in routine dental practice, has thereby been set at eight years for direct restorations and at ten years for indirect ones. Since the introduction of these guidelines, students do not learn to place amalgam at University. This pioneering work has found followers in many countries of Europe and similar standards, evaluation and teaching protocols have been established. However, several countries still rely on good old amalgam. The decision for a global phase-down of amalgam according to the "Minamata Convention on Mercury" will restrict the future use of amalgam despite its indisputable clinical indications and advantages. In countries where amalgam is still the material of choice to restore posterior teeth with proximal caries, great concerns, mainly about marginal long-term adaptation, wear rates and related failures of posterior composite restoration remain and have to be overcome. Current materials and technical concepts allow for high quality fillings, but composite materials require specific application techniques. Sensitive aspects include preparation steps, etching and priming, material insertion using incremental techniques and light curing under strict isolation. Postoperative aspects like finishing and polishing and maintenance are also of utmost importance. Considering all this, clinical data show that modern composite resin materials can allow for adequate and excellent long-term results, which are at least comparable to amalgam under the above-mentioned premises. Wear can be regarded as a shortcoming, but modification and changes in material characteristics have also led to significant improvements.