YATAY TARAMA GÖVDELERİ VARLIĞININ VE TARAMA STRATEJİSİNİN TAM ARK İMPLANT DESTEKLİ PROTEZLERDE DİJİTAL ÖLÇÜ DOĞRULUĞUNA ETKİSİ: İN VİTRO ÇALIŞMA

Abstract

VALIZADA N. Effect of the Presence of Horizontal Scan Bodies and Scanning Strategy on the Accuracy of Digital Impressions in Complete-Arch Implant-Supported Prostheses: An In Vitro Study. Hacettepe University, Faculty of Dentistry, Department of Prosthodontics, Specialty Thesis, Ankara, 2026. The aim of this in vitro study was to evaluate the effects of horizontal scan body usage and different scanning strategies on the accuracy of digital impressions for complete-arch implant-supported fixed prostheses. A mandibular edentulous stone model with six parallel implant analogs was used. A total of 120 digital scans were obtained (n = 10) using two scan body designs, three scanning strategies, and two intraoral scanners. The stone model was digitized with a laboratory scanner to generate the reference model. For all scans, a screw-retained one-piece framework was digitally designed, and the STL files were imported into an inspection software to assess impression accuracy. Frameworks from the reference and experimental models were superimposed, and deviation values were calculated for each implant. Significantly lower deviation values were observed in the horizontal scan body groups compared with the conventional scan body groups (p < 0.05). Scanning strategies significantly affected impression accuracy, with midline-initiated strategies providing more consistent and lower deviation values. However, some scanning directions did not show a statistically significant effect on accuracy (p > 0.05). Within the limitations of this in vitro study, digital impression accuracy in complete-arch implant-supported prostheses was significantly influenced by scan body design and scanning strategy. Horizontal scan bodies may be considered a promising option for improving digital impression accuracy by providing stable geometric reference structures.