## 1 Introduction  
The continuous advancement of technology in the field of dental medicine has enabled the gradual replacement of analogue methodologies with more advanced, faster,and more precise techniques. This shift has ultimately led to more comfortable and less time-consuming dental procedures for both patients and clinicians. The use of digital impressions, as opposed to conventional alginate or silicone impressions, exemplifies this development [1,2]. Impressions can be obtained using either conventional or digital approaches. Conventional impression-taking techniques present several disadvantages, including poor patient tolerance due to the texture, taste, and odor of the materials used, as well as the potential to trigger the gag reflex in susceptible patients. Some authors have described conventional impressions as one of the most unpleasant experiences during appointments for the fabrication of fixed, removable, and implant prostheses [3]. Digital impressions enabled the implementation of a fully digital workflow, based on computer-aided design and computer-aided manufacturing (CAD/CAM) technology, with the production of structures using 3D printers or milling machines. Moreover, the use of intraoral scanner (IOS) eliminates potential errors associated with conventional impressions, gypsum pouring, and model articulation. IOSs have also been reported to provide greater patient comfort and to enhance communication among all members of the dental team [4]. Digital impression systems are based on various technologies. On the one hand, photogrammetry devices determine the spatial positions of implants using calibrated marker coordinates and stereophotogrammetry to triangulate spatial relationships between implants. This approach is primarily used to enhance the accuracy and efficiency of digital workflows, particularly in implant-supported prosthodontics. On the other hand, IOSs operate through different mechanisms, such as confocal microscopy, 3D-in-motion video technology, and active triangulation [5,6]. Confocal microscopy acquires a series of sharply focused images at different depth levels. Only the light in focus is captured, reducing interference from blurred or out-of-focus regions and thereby improving accuracy. This technique generates high-resolution, color-accurate images and is especially effective in areas with significant depth variation [7]. The 3D-in-motion video technology combines structured light projection with real-time 3D video capture. As the device moves, it records a continuous stream of video frames and constructs a live 3D model through triangulation and point cloud processing. This method allows for smooth, continuous scanning and generates accurate full-color images [8]. Finally, the active triangulation technique captures the shape and position of oral structures--including teeth, gingiva, and implants--by projecting a structured light pattern (usually a laser or LED) onto the surface and detecting the deformation of this pattern with optical sensors [9]. These technological differences may influence scanning outcomes, particularly in complex clinical scenarios such as full-arch implant impressions or dedulous regions with limited anatomical landmarks. Until recently, digital implant impressions were considered less accurate than conventional impressions; however, more recent studies have reported inconsistent and sometimes comparable results [1,2]. The passive fit between prosthetic components and implants is one of the most important factors in implant-based rehabilitation. Its absence may lead to both biological and mechanical complications, ultimately compromising the long-term success of the treatment [6,10,11]. This concern stems from biomechanical considerations, particularly the risk of introducing excessive stress at the prosthesis-implant interface when tightening misfitting frameworks to osseointegrated implants.