Characteristics of intraoral scan bodies and their influence on impression accuracy: A systematic review

Abstract

ObjectiveThe aim of this systematic review was to evaluate the influence of the characteristics of intraoral scan bodies (ISBs) on the accuracy of intraoral scanning.Materials and MethodsAn electronic search was conducted through PubMed (MEDLINE), Scopus and Cochrane Library, up to March 2023. The literature search intended to retrieve all relevant clinical and in vitro studies about the effect that the various properties of ISBs may have on the accuracy (trueness and precision) of intraoral scanning. Only publications in English language were selected with animal studies, case reports, case series, technique presentation articles and expert opinions being excluded.ResultsA total of 28 studies met the inclusion criteria and were included in this systematic review. They were published between 2019 and 2023 and were all in vitro studies. Among the parameters described, the scan body material, position, geometry, height, diameter, and fixation torque were evaluated. The most common materials used for ISBs were polyetheretherketone (PEEK) and titanium alloys. The diameter and position of ISBs seemed to affect the trueness of implant impressions. Subgingival implant position and decreased ISB height affected negatively the trueness of scanning. Geometrical characteristics of ISBs also affect the implant impression accuracy, especially the bevel location and the types of designing modifications.ConclusionsThe characteristics of the currently used ISBs vary widely and the available scientific evidence is not yet conclusive about the optimal design of ISB. The implant impression accuracy achieved by any of the studied parameters is encouraging. Clinical studies are however necessary for more concrete conclusions.Clinical SignificanceISBs play a vital role in the digital workflow and influence significantly the accuracy and fit of implant restorations. More clinical trials are needed in order to conclude to the optimal characteristics of ISBs which would further enhance the success of the restorations.

In vitro comparison of accuracy between conventional and digital impression using elastomeric materials and two intra‐oral scanning devices

“…The design and material of the scanbody may influence the accuracy of digital impressions, as reported in a recent systematic review, 27 and currently various types of scanbodies have been introduced from all implant manufacturers. The depth of the implant, the fixing torque of the scanbody, the experience of the clinician, the distance between implants and even the multiple use of scanbodies have been reported as factors that potentially affect the accuracy of intraoral scanning of implants 28–35 …”

“…Silicone or polyether, open or closed impression tray technique are combining variables for the final result whereas digital impression is not affected by these factors and may explain its superior performance in certain clinical circumstances 24,25 . Accuracy of digital impressions, however, is affected by additional parameters excluding scanbodies which in total play a significant role in the efficacy of the clinical procedure 26–31 . Many studies agree that the impression of the fully edentulous mandible is a clinical challenge for both conventional and digital impression affected in accuracy by many variables 32–35 …”

The Influence of Laboratory Scanner versus Intra-Oral Scanner on Determining Axes and Distances between Three Implants in a Straight Line by Using Two Different Intraoral Scan Bodies: A Pilot In Vitro Study

“…The diameter and position of the ISB affect the trueness of implant impressions. After receiving the data from the scan, the software analyzes the data and defines the implants' longitudinal, vertical, and rotational axes [15,16]. Revilla-León et al reported that the optimal ISB design may vary depending on the intraoral scanner (IOS), the materials (PEEK or titanium), the implant angulation, the inter-implant distance, the implant depth, and other factors [17].…”