Abstract
Objectives: To present a detailed step-by-step protocol that utilizes oscillating instruments for refining feather-edge tooth preparations, eliminating undercuts, and enhancing intraoral scanner performance in digital prosthodontics. Methods: This technique begins with sulcus probing to determine a safe depth for subgingival preparation. Initial reduction is performed using rotary burs, followed by refinement with oscillating files of progressively finer grit. These files, which have a single active surface, enable the selective removal of undercuts while preserving soft tissue integrity. The protocol allows for immediate intraoral scanning without compromising the biological width. Results: The described technique produces smooth, undercut-free axial walls and subgingival margins that enhance scanner readability, minimize gingival trauma, and facilitate a seamless workflow from tooth preparation to intraoral scanning in a single visit. The resulting preparations are compatible with digital workflows, supporting precise fit and adaptation of final restorations. Conclusions: This article presents a new protocol for refining feather-edge tooth preparations using oscillating instruments to enhance the performance of intraoral scanners. The technique proposed herein is minimally invasive, precise, and adaptable, potentially improving scanning accuracy and restoration fit. However, additional clinical studies are necessary to confirm its effectiveness. Clinical significance: By eliminating undercuts and refining margins, this protocol ensures the acquisition of precise digital impressions in challenging subgingival areas. It enhances clinical efficiency by reducing chair time and soft tissue healing and facilitating immediate provisionalization and scanning. The approach is cost-effective, utilizes readily available tools, and improves the accuracy and predictability of digitally fabricated restorations.