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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).

Objectives: To assess navigation accuracy for complete‐arch implant placement with immediate loading of digitally prefabricated provisional. Materials and Methods: Consecutive edentulous and terminal dentition patients requiring at least one complete‐arch FDP were treated between December 2020 and January 2022. Accuracy was evaluated by superimposing pre‐operative and post‐operative cone beam computed tomography (CBCT), recording linear (mm) and angular (degrees) deviations. T‐tests were performed to investigate the potential effect of the registration algorithm (fiducial‐based vs. fiducial‐free), type of references for the fiducial‐free algorithm (teeth vs. bone screws), site characteristic (healed vs. post‐extractive), implant angulation (axial vs. tilted), type of arch (maxilla vs. mandible) on the accuracy with p‐value <0.05. Results: Twenty‐five patients, 36 complete‐arches, and 161 implants were placed. The overall mean angular deviation was 2.19° (SD 1.26°). The global platform and apex mean deviations were 1.17 mm (SD 0.57 mm), and 1.30 mm (SD 0.62 mm). Meaningful global platform (p = 0.0009) and apical (p = 0.0109) deviations were experienced only between healed and post‐extraction sites. None of the analyzed variables significantly influenced angular deviation. Minor single‐axis deviations were reported for the type of jaw (y‐axis at implant platform and apex), registration algorithm (y‐axis platform and z‐axis deviations), and type of references for the fiducial‐free algorithm. No statistically significant differences were found in relation to implant angulation. Conclusions: Within the study limitations navigation was reliable for complete‐arch implant placement with immediate loading digitally pre‐fabricated FDP. AI‐driven surface anatomy identification and calibration protocol made fiducial‐free registration as accurate as fiducial‐based, teeth and bone screws equal as references. Implant site characteristics were the only statistically significant variable with healed sites reporting higher accuracy compared to post‐extractive. Live‐tracked navigation surgery enhanced operator performance and accuracy regardless of implant angulation and type of jaw. A mean safety room of about 1 mm and 2° should be considered. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Implant abutment connection was described among the main causes of peri-implant bone resorption. The aim of this in vitro study was to test the coupling capacity, the surface modification of a new hybrid connection and the influence of repeated connection activations caused during the main clinical and laboratory phases. A total of 40 implant-abutment screw retained systems with 10°-conical and internal hexagon connection were tested. The connection was screwed, fixed to the universal test machine, removed the screw and a pull-out test was performed. Test was repeated five times in succession. Also Scanning Electron Microscopy (SEM) was used to detect microscopically surface modification. Analysis of variance and Tukey tests were used for the statistical analysis. Pull-out test reveals a mean value of 131.35 ± 16.52 Newton Centimeter (N·cm). For each single activation, results from first to fifth were: 113.9 ± 13.02, 126.1 ± 12.81, 138.11 ± 15.15, 138.8 ± 11.90 and 140 ± 12.99 N·cm. A statistically significant difference between the measurements and an increase in the removal force was shown. The collected data supports the use of this new type of connection, resulting in a very strong interface between implant and abutment. Also, repeated activation of connection can promote a better coupling of the implant-abutment interface. [ABSTRACT FROM AUTHOR]

The growing interest in minimally invasive implant placement and delivery of a prefabricated provisional prosthesis immediately, thus minimizing "time to teeth," has led to the development of numerous 3-dimensional (3D) planning software programs. Given the enhancements associated with fully digital workflows, such as better 3D soft-tissue visualization and virtual tooth rendering, computer-guided implant surgery and immediate function has become an effective and reliable procedure. This article describes how modern implant planning software programs provide a comprehensive digital platform that enables efficient interplay between the surgical and restorative aspects of implant treatment. These new technologies that streamline the overall digital workflow allow transformation of the digital wax-up into a personalized, CAD/CAM-milled provisional restoration. Thus, collaborative digital workflows provide a novel approach for time-efficient delivery of a customized, screw-retained provisional restoration on the day of implant surgery, resulting in improved predictability for immediate function in the partially edentate patient.