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Purpose: To assess and compare the accuracies of intraoral scanners (IOS) and stereophotogrammetry (SPG) devices for complete-arch digital implant impressions., Methods: A 4-analog model was digitized using a desk scanner to obtain a reference file. Thirty test scans were conducted using the investigated IOS device, while an additional 30 scans were performed using the SPG device. Using the best-fit algorithm, the resulting 60 test files were aligned with the reference file. Linear (ΔX, ΔY, and ΔZ-axis) and angular deviations (ΔANGLE) were evaluated. Three-dimensional (3D) deviation was calculated based on the Euclidean distance (ΔEUC). The analysis was stratified according to the scanning device and implant position. Fisher's F and t-tests were used to compare the variances and expected values of the two scanning systems., Results: IOS expressed a higher 3D (ΔEUC) mean deviation than SPG (52.8 µm vs. 33.4 µm, P < 0.0001), with extreme measurements up to 181.9 µm. A significantly higher standard deviation (SD) was associated with IOS (37.1 µm vs. 17.7 µm, P < 0.0001). Considering angular deviations, the IOS showed slightly higher angular mean deviations (ΔANGLE) than the SPG (0.28° vs. 0.24°, P = 0.0022), with extreme measurements of up to 0.73°. The SPG SD values were significantly lower than the IOS SD values (0.14° vs. 0.04°, P < 0.0001)., Conclusions: The SPG showed significantly higher 3D and angular accuracies for complete arch implant impressions, with consistent repeatability. IOS scanning revealed significantly higher extreme deviations exceeding the acceptable threshold value. Despite study limitations, SPG appears more feasible than IOS for complete-arch digital implant impressions.

Purpose: To introduce a digitally assisted technique to achieve the ideal soft and bone tissue interface for anatomic-driven pink free implant supported fixed prosthesis, and prefabricate an interim prosthesis to be used the day of the surgery as a prosthetic scaffold to condition the healing., Methods: The digital assisted soft tissue sculpturing (DASS) technique allows the previsualization of the ideal soft and bone tissue interface and fabricate a computer aided design computer aided manufacturing (CAD-CAM) anatomic-driven pink free complete arch interim prosthesis for the immediate loading. Bone and soft tissue interface as well as the interim prosthesis design are performed in a segmented multiple standard tessellation language (STL) file embedding the bone anatomy, the intraoral surface anatomy (dental and soft tissue), the digital wax-up and the implant positioning. The interim prosthesis is used as a prosthetic scaffold to guide the soft and bone tissue surgical sculpturing and regeneration., Conclusions: The DASS technique is a predictable integrated digital workflow that simplifies the achievement of a scalloped tissue interface for pink free fixed implant prosthesis, reestablishing the mucosal dimension required for the protection of underlying bone while maintaining tissue health. The surgical sculpturing and maturation of the soft and bone tissue is driven and enhanced by the xenogeneic collagen matrix grafting and prosthetic scaffold effect of the digitally prefabricated interim prosthesis delivered the day of the surgery.

Purpose: To evaluate the influence of implant scanbody (ISB) material, position and operator on the accuracy of a confocal microscopy intraoral scanning (IOS) for complete-arch implant impression., Methods: An edentulous maxillary model with 6 internal hexagonal connection analogues was scanned with an extraoral optical scanner to achieve a reference file. Three ISBs made of different materials (polyetheretherketone (Pk), titanium (T) and Pk with a titanium base (Pkt)) were scanned with IOS by 3 operators. The resulting 45 test files were aligned to the reference file with a best fit algorithm. Linear (ΔX, ΔY and ΔZ-axis) and angular deviations (ΔANGLE) were assessed. Absolute values of the linear discrepancies were summed up to obtain a global measure of linear absolute error (ΔASS). Influence of ISB material, position and operator was statistically assessed using the mixed general linear model., Results: At multivariate analysis, whenΔASS was considered as response variable, it was identified a significant influence of material (p<0.0001) and position (p=0.0009) while no significant operator effect was detected. When ΔANGLE was considered as response variable, material and position significantly influenced the expected ΔANGLE (p=0.0232 and p<0.0001) and no operator effect was identified., Conclusions: The investigated IOS for complete-arch digital impression was influenced by the ISB material with peek reporting the best results on both linear and angular measurements followed by titanium, peek-titanium resulting as the less accurate. Implant angulation affected significantly the linear deviations while implant position the angular deviations. Operator did not show any significant effect on the IOS accuracy., (Copyright © 2019 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.)

Purpose: To introduce a proof of concept technique and new integrated workflow to optimize the functional and esthetic outcome of the implant-supported restorations by means of a 3-dimensional (3D) facially-driven, digital assisted treatment plan., Methods: The Smiling Scan technique permits the creation of a virtual dental patient (VDP) showing a broad smile under static conditions. The patient is exposed to a cone beam computed tomography scan (CBCT), displaying a broad smile for the duration of the examination. Intraoral optical surface scanning (IOS) of the dental and soft tissue anatomy or extraoral optical surface scanning (EOS) of the study casts are achieved. The superimposition of the digital imaging and communications in medicine (DICOM) files with standard tessellation language (STL) files is performed using the virtual planning software program permitting the creation of a VDP., Conclusions: The smiling scan is an effective, easy to use, and low-cost technique to develop a more comprehensive and simplified facially driven computer-assisted treatment plan, allowing a prosthetically driven implant placement and the delivery of an immediate computer aided design (CAD) computer aided manufacturing (CAM) temporary fixed dental prostheses (CAD/CAM technology)., (Copyright © 2018 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.)