OWN - Quintessence Publishing Company, Ltd. CI - Copyright Quintessence Publishing Company, Ltd. OCI - Copyright Quintessence Publishing Company, Ltd. TA - Int J Oral Maxillofac Implants JT - The International Journal of Oral & Maxillofacial Implants IS - 1942-4434 (Electronic) IS - 0882-2786 (Print) IP - 5 VI - 37 PST - ppublish DP - 2022 PG - 997-1002 LA - en TI - Accuracy of Impression Techniques for Dental Implants Placed in Five Different Orientations LID - 10.11607/jomi.9441 [doi] FAU - Kim, Hyo-Seon AU - Kim H FAU - Lee, Jae-Hyun AU - Lee J FAU - Lee, Su Young AU - Lee S CN - OT - angulation OT - dental implant OT - dental impression materials OT - dental impression technique OT - impression accuracy OT - trueness AB - Purpose: The purpose of this study was to evaluate the impression accuracy of two implants placed in different orientations and compare the impression accuracy obtained with the dual-arch impression technique using hybrid impression copings and the conventional open-tray impression technique. Materials and Methods: Five mandibular dentiform models were prepared by placing implants in the second premolar and second molar regions in the following different orientations: parallel to each other; 15-degree mesiodistal angulation; 30-degree mesiodistal angulation; 15-degree buccolingual angulation; and 30-degree buccolingual angulation. After making 10 impressions for each model with the open-tray impression technique and dual-arch impression technique with hybrid impression copings, cast models were fabricated for each impression (n = 10). Scan bodies were mounted on the five dentiform models and the fabricated 100 cast models were scanned using a desktop scanner. The three-dimensional deviation of the scan bodies on the cast models was calculated and compared to the reference data from the dentiform models. A two-way analysis of variance was conducted (α = .05). Results: The root mean square deviation values obtained from the implants placed with 30-degree mesiodistal angulation were 93.05 ± 6.21 μm with the open-tray impression technique and 104.01 ± 8.89 μm with the dual-arch impression technique, which were the largest deviation values for both techniques (P < .001). Compared to the open-tray impression technique, the dual-arch impression technique with the hybrid impression copings showed significantly lower accuracy when the angulation between the implants was 15 degrees mesiodistally (P < .001), 30 degrees mesiodistally (P = .016), or 30 degrees buccolingually (P < .001). However, there was no significant difference between the accuracy of the two impression techniques for parallel implants (P = .74). Conclusion: When the two implants were inclined 30 degrees mesiodistally, both implant impression techniques showed the largest deviation and the dual-arch impression technique showed lower accuracy compared to the conventional open-tray impression technique. Parallel placement of implants may improve impression accuracy and enable use of the dual-arch impression technique. AID - 3500749