The two-step direct composite restoration (R2 restoration) – a current review

Introduction: The treatment of subgingival cavities with direct composite restorations is a challenge in everyday dental practice. Many difficulties must be overcome in the course of treatment, including bleeding and tissue management, a flawless adhesive technique, step-free and margin-free application of the restorative material as well as anatomically correct crown shaping and contact area design. Each individual treatment step in the course of the restorative process is crucial for the long-term clinical success of the restoration. Treatment methods: The R2 restorations divide this complex restorative process into two steps. In the first restorative step, only the deep subgingival portion of the cavity is restored, and the cavity floor is elevated to a paragingival or slightly supragingival level. In the second restorative step, the tooth's crown is reconstructed, and the contact area facing the neighboring tooth is designed. The two restorative steps require the use of various tools and techniques. Result: The methodical, step-by-step approach makes the entire treatment process more manageable and easier to perform. Conclusion: Teeth with extensive tooth substance loss as a result of deep subgingival cavities can be restored safely, predictably and with a good prognosis by means of the R2 restorations. Structured follow-up care which focuses on sufficient cleaning of the proximal area is essential for long-term success. Keywords: MMPs, adhesives, contamination, resin composites, technique sensitivity