Evaluation of the accuracy of three different intraoral scanners for endocrown digital impression: An in vitro study

Background: Intraoral scanners (IOSs) in implantology represent a viable approach for single teeth or partial arches. However, when used for complete edentulous arches or long-span edentulous areas, it has been demonstrated that there is a need for improvement of IOS-related techniques. Therefore, the aim of this in vitro study was to assess the trueness and precision of a complete arch digital impression on four and six implants taken with or without a customized, prosthetic-based impression template. Materials and Methods: Two experimental models were prepared, representative of a complete edentulous mandible restored with four and six implants with built-in scan abutments. Models were scanned with (test group, TG) or without (control group, CG) the prosthetic-based impression template. Eight scans were taken for each model. The time needed to take impressions, error, trueness, and precision were evaluated. A statistical analysis was performed. Results: In the case of four implants, the time needed for the impression was 128.7 ± 55.3 s in the TG and 81.0 ± 23.5 s in the CG (p = 0.0416). With six scan abutments, the time was 197.5 ± 26.8 and 110.6 ± 25.2 s in the TG and CG, respectively (p = 0.0000). In the TG, no errors were experienced, while in the CG, 13 impressions were retaken due to incorrect stitching processes. In the four-implant impression, the mean angle deviation was 0.252 ± 0.068° (95% CI 0.021–0.115°) in the CG and 0.134 ± 0.053° (95% CI 0.016–0.090°) in the TG. The difference was statistically significant (p = 0.002). In the six-implant impression, the mean angle deviation was 0.373 ± 0.117° (95% CI 0.036–0.198°) in the CG and 0.100 ± 0.029° (95% CI 0.009–0.049°) in the TG (p = 0.000). In the TG, there were no statistically significant differences in the mean angle deviation within the group (p > 0.05), but there were in the CG. A colorimetric analysis showed higher deviations from the original model for the six-implant impression without a prosthetic template. Conclusions: Although all of the impressions exhibited deviation from the original model in the range of clinical acceptability, the prosthetic-based impression template significantly improved the trueness and precision of complete edentulous arches rehabilitated with four or six implants, making the complete arch digital impression more predictable.

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The Effect of Different Pouring Interval of Conventional Impression on the Marginal Accuracy of Full Contour Zirconia Crowns in Comparison with Digital Impression : An In Vitro Study

Journal of Baghdad College of Dentistry ◽

10.12816/0046306 ◽

2018 ◽

Vol 30 (1) ◽

pp. 17-22

Author(s):

Elaf A. Hadi ◽

Adel F. Ibraheem

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Digital Impression ◽

Zirconia Crowns ◽

Conventional Impression

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Accuracy of Ceramic Restorations Made Using an In-office Optical Scanning Technique: An In Vitro Study

Operative Dentistry ◽

10.2341/12-309-l ◽

2014 ◽

Vol 39 (3) ◽

pp. 308-316 ◽

Cited By ~ 24

Author(s):

P Tidehag ◽

K Ottosson ◽

G Sjögren

Keyword(s):

Glass Ceramic ◽

In Vitro Study ◽

Vitro Study ◽

Digital Impression ◽

All Ceramic ◽

Computer Aided ◽

Cad Cam ◽

Ceramic Crowns ◽

Ceramic Crown

SUMMARY The present in vitro study concerns determination of the pre-cementation gap width of all-ceramic crowns made using an in-office digital-impression technique and subsequent computer-aided design/computer-aided manufacturing (CAD/CAM) production. Two chairside video camera systems were used: the Lava Oral scanner and Cadent's iTero scanner. Digital scans were made of a first molar typodont tooth that was suitably prepared for an all-ceramic crown. The digital impressions were sent via the Internet to commercial dental laboratories, where the crowns were made. Also, an impression of the typodont tooth was made, poured, and scanned in order to evaluate the pre-cementation gap of crowns produced from scanning stone dies. These methods and systems were evaluated by creating replicas of the intermediate space using an addition-cured silicone, and the gap widths were determined using a measuring microscope. Hot-pressed leucite-reinforced glass-ceramic crowns were selected as a reference. The mean value for the marginal measuring points of the control was 170 μm, and the values for all the evaluated crowns ranged from 107 to 128 μm. Corresponding figures for the internal measuring points were 141-210 μm and 115-237 μm, respectively. Based on the findings in the present study, an in-office digital-impression technique can be used to fabricate CAD/CAM ceramic single crowns with a marginal and internal accuracy that is on the same level as that of a conventional hot-pressed glass-ceramic crown. In the present study, however, slight differences could be seen between the two types of ceramic crowns studied with respect to the internal fit obtained.

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The Effect of Different Pouring Interval of Conventional Impression on the Marginal Accuracy of Full Contour Zirconia Crowns in Comparison with Digital Impression : An in Vitro Study

Journal of Baghdad College of Dentistry ◽

10.12816/0042984 ◽

2017 ◽

Vol 29 (4) ◽

pp. 1-6

Author(s):

Elaf A. Hadi ◽

Adel F. Ibraheem

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Digital Impression ◽

Zirconia Crowns ◽

Conventional Impression

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Accuracy of Implant Level Intraoral Scanning and Photogrammetry Impression Techniques in a Complete Arch with Angled and Parallel Implants: An In Vitro Study

Applied Sciences ◽

10.3390/app11219859 ◽

2021 ◽

Vol 11 (21) ◽

pp. 9859

Author(s):

Hani Tohme ◽

Ghida Lawand ◽

Rita Eid ◽

Khaled E. Ahmed ◽

Ziad Salameh ◽

...

Keyword(s):

In Vitro Study ◽

High Accuracy ◽

Vitro Study ◽

Digital Impression ◽

P Value ◽

Angular Deviation ◽

Digital Photogrammetry ◽

Intraoral Scanning ◽

Optical Markers

(1) Background: Stereophotogrammetry has recently been investigated showing high accuracy in complete implant supported cases but has scarcely been investigated in cases of tilted implants. The aim of this in vitro study was to compare the accuracy of digital impression techniques (intraoral scanning and photogrammetry) at the level of intraoral scan bodies in terms of angular deviations and 3D discrepancies. (2) Methods: A stone master cast representing an edentulous maxilla using four implant analogs was fabricated. The two anterior implants were parallel to each other, and the two posterior implants were at an angulation of 17 degrees. Digital intraoral scanning (DIOS) impressions were taken after connecting implant level scan bodies to the master cast and STL files were exported (n = 15). Digital photogrammetry (DPG) impressions were captured using a PiC Camera after tightening implant level PiC optical markers and STL files were exported (n = 15). Superimposition was carried out by a software for determining the accuracy of both. (3) Results: Significant angular discrepancies (ΔA) and 3D deviations of scan bodies were found among the groups in trueness with lower deviations for the DPG (p value < 0.001). However, trueness within ISBs varied between angular and 3D deviations and outcomes were not specific to determine the effect of implant angulation. In precision, no significant differences were detected within ISBs and among both groups in terms of angular deviation. However, DPG had less deviations than DIOS group in terms of 3D deviations (p value < 0.001). (4) Conclusion: Digital photogrammetry technique conveyed the utmost accuracy in both trueness and precision for the intraoral scan bodies among both impression methods assessed. In addition, implant angulation did not influence the precision of the impression techniques but affected their trueness without explicit conclusions.

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