The Effects of Angulation and Interimplant Distance on the Trueness of Different Impression Techniques: An In Vitro Study

positioning.While angulation can enhance primary stability, it can also increase impression distortion during tray removal. 10,11Similarly, nonideal interimplant distances dictated by clinical constraints can also reduce trueness for both conventional and digital methods. 8revious research 2,4,5,12 has examined these parameters with varying conclusions.Studies 2,5 have reported that implant angulation adversely affects impression accuracy, particularly with IntroductIonThe long-term stability of implant-supported prostheses depends largely on achieving a passive fit between the framework and implants.Unlike natural teeth surrounded by the periodontal ligament, implants are rigidly osseointegrated in the bone. 1 Even small misfits can transmit excessive stress, leading to prosthetic fractures, discomfort, bone resorption, or loss of osseointegration. 2 Since complete passive fit is impossible to achieve, the goal of the dental impression is to minimize discrepancies when fabricating the prosthetic components.The reliability of impressions, which determine the three-dimensional relationship of implants on the working cast, is essential for this process. 3,4onventional elastomeric impressions are widely used in implant dentistry. 5Two main methods are available: the direct (open tray) method, where copings remain in the impression, and the indirect (closed tray) method, where copings are repositioned after removal.A snap-fit system has also been introduced as a hybrid technique to reduce transfer errors. 6Although digital impressions are increasingly common, conventional methods remain the standard in many clinical settings.In particular, longspan restorations and angulated implants have shown better trueness with conventional techniques. 7Conventional impressions are also preferred because of their accessibility and methodological consistency across clinics and laboratories. 8,9deal vertical implant placement is not always possible.Resorbed ridges or close proximity to anatomical structures can require angulated