Influence of scan body geometry on the trueness of intraoral scanning

Effect of a Novel ‘Scan Body’ on the In Vitro Scanning Accuracy of Full-Arch Implant Impressions

Effect of scan body designs and internal conical angles on the 3-dimensional accuracy of implant digital scans

In implant dentistry, the advent of intraoral scanning technology has revolutionized traditional clinical processes by streamlining procedures and ensuring predictable treatment outcomes. However, achieving accurate virtual implant positions using intraoral scanners and scan bodies can be influenced by various clinical and laboratory factors. This study aims to investigate the impact of scan body image capture deficiency and scan body alignment methods in computer-aided design (CAD) software on the accuracy of virtual implant positions, particularly in different implant depths. Three stereolithographic half-arch implant models with different implant depths were prepared, representing three scenarios of scan body exposure: full exposed scan body, 2/3 exposed scan body, and 1/3 exposed scan body. The scan body image capture deficiency and alignment methods were simulated using CAD software. The deviation of virtual implant positions obtained from different scenarios were evaluated using 3D analysis software. The highest angular and linear deviation (0.237±0.059 degrees, 0.084±0.068 mm) were found in the 1/4 upper and lower part scan body deficiency using the 1-point alignment method in the 1/3 exposed scan body. Two-way ANOVA analysis revealed significant effects of scan deficiency on virtual implant position deviations across all scan body exposures, except for the linear deviation when the scan body was exposed 2/3 of its length. Furthermore, scan deficiencies in the 1/4 upper and lower parts of the scan body significantly affected implant angular deviation regardless of scan body exposure, while implant linear deviation was specifically affected when the scan body was exposed to only 1/3 of its total length. Deficiencies in scan body acquisition, particularly in deep soft tissue situations, can lead to deviations in both angular and linear positioning of virtual implants. Employing appropriate scan body alignment methods such as a 3-point alignment approach demonstrates better accuracy compared to a 1-point alignment.

In implant dentistry, the advent of intraoral scanning technology has revolutionized traditional clinical processes by streamlining procedures and ensuring predictable treatment outcomes. However, achieving accurate virtual implant positions using intraoral scanners and scan bodies can be influenced by various clinical and laboratory factors. This study aims to investigate the impact of scan body image capture deficiency and scan body alignment methods in computer-aided design (CAD) software on the accuracy of virtual implant positions, particularly in different implant depths. Three stereolithographic half-arch implant models with different implant depths were prepared, representing three scenarios of scan body exposure: full exposed scan body, 2/3 exposed scan body, and 1/3 exposed scan body. The scan body image capture deficiency and alignment methods were simulated using CAD software. The deviation of virtual implant positions obtained from different scenarios were evaluated using 3D analysis software. The highest angular and linear deviation (0.237±0.059 degrees, 0.084±0.068 mm) were found in the 1/4 upper and lower part scan body deficiency using the 1-point alignment method in the 1/3 exposed scan body. Two-way ANOVA analysis revealed significant effects of scan deficiency on virtual implant position deviations across all scan body exposures, except for the linear deviation when the scan body was exposed 2/3 of its length. Furthermore, scan deficiencies in the 1/4 upper and lower parts of the scan body significantly affected implant angular deviation regardless of scan body exposure, while implant linear deviation was specifically affected when the scan body was exposed to only 1/3 of its total length. Deficiencies in scan body acquisition, particularly in deep soft tissue situations, can lead to deviations in both angular and linear positioning of virtual implants. Employing appropriate scan body alignment methods such as a 3-point alignment approach demonstrates better accuracy compared to a 1-point alignment.

Accuracy of different digital scanning techniques and scan bodies for complete-arch implant-supported prostheses

Influence of scan body design on accuracy of the implant position as transferred to a virtual definitive implant cast

Objective: To compare the accuracy of intraoral scanning for complete-arch implant-supported fixed prosthesis using umbrella scan bodies (USB) and conventional scan bodies (CSB), providing a reference for the clinical application of umbrella-shaped scanning bodies. Methods: A new type of umbrella-shaped scanning body and its matching auxiliary bar were independently developed. A maxillary type Ⅳ dental stone model with six parallel implant abutment analogs was fabricated. Conventional scanning bodies were installed on the model, and a laboratory scanner was used to scan the model as reference data. The CSB, USB, and USB combined with an auxiliary bar (U+SB) were installed on the model, respectively. A single attending physician performed intraoral scanning 10 times for each group using an intraoral scanner, serving as test group data (CSB, USB, U+SB). The test data were best-fit aligned with the virtual abutment models generated from the reference data. The trueness and precision of root-mean-square error (RMSE) values, inter-abutment distance deviations, angular deviations, and scanning time were measured and calculated. Repeated measures ANOVA and generalized estimating equation models were used for statistical analysis. Results: The trueness of RMSE values [(48.0±12.6) and (45.9±13.4) μm] and distance deviations [(64.5±60.2) and (63.8±54.4) μm] of the USB and U+SB groups were significantly better than those of the CSB group [(81.9±23.9) and (90.0±85.2) μm] (all P<0.05). There was no significant difference in trueness of RMSE values and distance deviations between the USB group and U+SB group (all P>0.05). There were no significant differences in the precision of RMSE values and angular deviations among the three groups (all P>0.05). The scanning time of the USB group and U+SB group [(54.3±11.8) and (35.8±10.1) s] was significantly shorter than that of CSB group [(108.7±38.9) s] (all P<0.05). Conclusions: Compared with conventional scanning bodies, the new umbrella-shaped scanning body demonstrates higher accuracy and efficiency for intraoral scanning impressions in complete-arch implant-supported fixed prosthesis.

Optical transfer is realized with system-specific transfer posts (scan bodies) mounted on dental implants or on implant analogs. This study presents a novel algorithm for creation of geometry on the surface of dental implant scan bodies and examines the precision of the optical acquisition of scan bodies and the precision of the position of the screw-tightened scan bodies on dental implant analogs. Scan bodies of two different implant manufacturers (S1, S2), one with a horizontal and two with different conical implant-abutment geometries were screw tightened to implant analogs in stone casts with a 10 Ncm torque. The stone casts were scanned ten times with a dental lab scanner. Each scan body was removed and positioned ten times; after each repositioning, a scan was performed. The cylinder axis of every scan body and the occlusal horizontal scan body surface was virtually reconstructed. At the intersection of the cylinder axis and the horizontal plane a point was marked. The mean deviation of this point in consecutive scans and the angle between the scan body axes in the virtual models were measured, and the standard deviation was calculated. Statistical significance of the results was tested with a Kruskal-Wallis Test and Mann-Whitney U-test for pairwise comparison (p < 0.05). The mean deviation of the angle between two scan bodies was 0.05° (SD 0.04°) (S1) and 0.14° (SD 0.08°) (S2). After detachment and repositioning of the scan bodies the mean deviation was 0.05° (SD 0.03°) (S1) and 0.16° (SD 0.08°) (S2). The mean deviation of the central point was 5.7 μm (SD 3.4 μm) without detachment and 4.9 μm (SD 2.6 μm) after detachment and repositioning (S1). For system S2 the mean deviation of the central point was 13.4 μm (SD 7.2 μm) after repeated scanning and 15 μm (SD 5 μm) after detachment, repositioning, and repeated scanning. The precision of extraoral scanning of scan bodies is dependent on the scan body surface design and geometry. The precision of scanning with an extraoral model scanner differed between the scan body geometries and inter-scan body distances. The precision of dental implant scan body scanning was not significantly influenced by detachment and repositioning of the scan body.

Intraoral scan bodies in implant dentistry: A systematic review

Complete arch digital implant scan accuracy with screw-retained or snap-on scan bodies: A comparative in vitro study.

Scanning accuracy of abutment level scan body according to insertion angles and depths of dental implants.

Sufficient data are not currently available on how the various geometries of scan bodies and different scan strategies affect the quality of digital impressions of implants. The purpose of this study was to present new data on these two topics and give clinicians a basis for decision making. A titanium master model containing three Nobelreplace Select™ implants (Nobelbiocare Services AG, Zurich, Switzerland) was digitized using an ATOS industrial noncontact scanner. Digitization was repeated three times with different types of scan bodies integrated into the implants: ELOS A/S, nt-trading GmbH, and TEAMZIEREIS GmbH. These three scans served as virtual master models. The titanium master model was then scanned with the TRIOS3© digital intraoral scanner (ELOS A/S, Copenhagen, Denmark), which was used for two different scanning strategies. Strategy A was a one-step procedure that included both the titanium master model and the integrated scan bodies. Strategy B comprised two steps. First, a digital overlay was performed with a scan of the titanium master model without integrated scan bodies. A second scan was performed with the titanium master model and integrated scan bodies. By repeating both strategies 10 times for each type of scan body, 60 scans were generated and the corresponding standard tessellation language data sets overlaid with the corresponding virtual master model. Deviations in the resulting superimpositions were calculated and evaluated separately in the individual axes (x, y, z) and in three-dimensional space (Euclidean distance). Statistical evaluation was performed using the R-project software. Level of significance was determined at p ≤ 0.05. With regard to the geometry of the scan bodies, strategy A significantly influenced the accuracy of the digital implant impression in regards to Euclidean distance (p = 0.003). No significant difference was found for strategy B in this context. Comparing the two scan strategies revealed that strategy A achieved significantly higher accuracy overall (p = 0.031). The quality of digital intraoral impressions seems to be influenced by both the geometry of the scan body and the scan strategy. For clinical practice, the one-step scan strategy seems beneficial. Furthermore, the scan bodies of ELOS A/S showed a potential clinical advantage.

A report on some typical cases of malocclusion with methods of treatment

Background/Objectives: Accurate implant impressions are critical for capturing the three-dimensional (3D) spatial positioning of implants. Digital workflows using intraoral scanners (IOSs) and scan bodies offer distinct advantages over conventional elastomeric techniques. However, the geometry of scan bodies may influence the precision and trueness of IOS-acquired data, and optimal design parameters remain undefined. This systematic review aims to evaluate the effects of scan body geometry on the trueness of digital implant impressions captured using IOSs. Methods: A systematic search was conducted across PubMed, Scopus, EMBASE, Web of Science, the Cochrane Library, and Google Scholar up to 25 February 2025. Eligible studies assessed the impact of scan body geometry on the accuracy of implant-level impressions acquired with IOSs. Study quality was assessed using the Quality Assessment Tool for In Vitro Studies of Dental Materials (QUIN). Results: Twenty-eight studies were included, of which twenty-six were in vitro. The included studies, published between 2020 and 2025, demonstrated that variations in macro- and micro-geometries influenced both linear and angular trueness. Cylindrical designs with optimal dimensions generally outperformed cuboidal or spherical forms. Structural modifications, such as rigid bar extensions and surface facets, often improved scan accuracy. Some hybrid or modified designs performed comparably to conventional scan bodies. According to QUIN, 27 studies were moderate quality and one had high quality. Conclusions: Scan body geometry affected the accuracy of intraoral implant digital impressions. Designs featuring rigid extensions or simplified geometries improve trueness and precision. Further standardized clinical studies are needed to define optimal design features and validate current in vitro findings.

Effect of shape and size of implant scan body on scanning accuracy: an in vitro study.