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Purpose: Dynamic navigation is a technique that allows for the placement of dental implants using a computer-guided approach according to preoperative planning. Its accuracy has been assessed in several previous studies. The purpose of this study was to summarize data on implant placement accuracy using dynamic navigation, to synthesize the frequency of intraoperative complications and implant failures, and to compare this technique with static computer-guided surgery and a freehand approach. Materials and methods: Electronic and manual literature searches until December 2019 were performed. The outcome variables were implant placement accuracy using dynamic navigation, accuracy differences between dynamic and static techniques and between dynamic and freehand techniques, intraoperative complications, and implant failures. Random-effects meta-analyses were performed. Results: A total of 32 studies were included; 29 reported accuracy values (2,756 implants), and 10 focused on complications and implant failures (1,039 implants). The pooled mean implant placement errors were 0.81 (95% CI: 0.677 to 0.943) mm at the entry point and 0.910 (95% CI: 0.770 to 1.049) mm at the apical point. The pooled mean vertical and angular deviations were 0.899 (95% CI: 0.721 to 1.078) mm and 3.807 (95% CI: 3.083 to 4.530) degrees. The navigation group showed significantly lower implant placement errors with respect to the freehand technique (P < .01) and similar accuracy values (P ≥ .05) compared with the static technique. The pooled prevalence of failures was 1% (95% CI: 0.00% to 2%). Conclusion: Dynamic navigation provided small implant placement errors, comparable with those obtained using static computer-guided surgery, and can be considered a more accurate technique than conventional freehand surgery.

New 3D digital technologies can be applied to implant-supported ear prostheses to restore anatomical structures damaged by cancer, dysplasia, or trauma. However, several factors influence the accuracy of implant positioning using a cranial template. This pilot study describes an innovative navigated flapless surgery for craniofacial implants, prosthetically guided by 3D planning of the ear prosthesis. Laser surface scanning of the face allowed for mapping of the healthy ear onto the defect site, and projection of the volume and position of the final prosthesis. The projected ear volume was superimposed on the skull bone image obtained by cone-beam computed tomography (CBCT), performed with the navigation system marker plate positioned in the patient's mouth. The craniofacial implants were fitted optimally to the ear prosthesis. After system calibration, real-time navigated implant placement based on the virtual planning was performed with minimally invasive flapless surgery under local anesthesia. After 3 months of healing, digital impressions of the implants were made, and the digital manufacturing workflow was completed to manufacture the ear prosthesis anchored to the craniofacial implants. The proposed digital method facilitated implant positioning during flapless surgery, improving the ear prosthesis manufacturing process and reducing operation time, patient morbidity, and related costs. This protocol avoids the need for a reference tool fixed in the cranial bone, as is usually required for maxillofacial surgery, and confirmed that surgical navigation is useful for guiding the insertion of craniofacial implants during flapless surgery.

BACKGROUND To compare the accuracy of 3 different devices for facial images acquisition, useful for prosthodontic esthetic preview. METHODS Bidimensional extraoral photographs (Nikon D300), facial scans (Bellus3D) and 3D digital stereophotogrammetry photos (3dMD Face System) were acquired from 15 patients. The intraoral impressions of all subjects were digitally taken through a scanner (i500; Medit). Files obtained from each acquisition method were transferred on Exocad Software, and the measurements of the frontal teeth were performed and compared with those of the intraoral scans, assumed as reference. The data were statistically analyzed (Friedman and Dunn tests) with P

Objectives: The use of digital devices is strongly influencing the dental rehabilitation workflow both for single-crown rehabilitation and for full-arch prosthetic treatments. Methods: In this study, trueness was analyzed by overlapping the scan dataset made with Medit I-500 (by using two different tips and two different scan strategies) with the scan dataset made with lab scanning, and the values of the (90°–10°)/2 method were reported. Precision was evaluated by using the same values of trueness coming from the intra-group overlapping (scan dataset made with an IOS overlapped and compared to each other). Moreover, two different software programs of overlapping were used to calculate accuracy values. Results: The mean difference of trueness was 26.61 ± 5.07 µm with the suggested strategy of intraoral scanning and using a new design of the tip, 37.99 ± 4.94 µm with the suggested strategy of intraoral scanning and using the old design of the tip, and 51.22 ± 6.57 µm with a new strategy of intraoral scanning and using the old design of the tip. The mean difference of precision was 23.57 ± 5.77 µm with the suggested strategy of intraoral scanning and using a new design of the tip, 38.34 ± 11.39 µm with the suggested strategy of intraoral scanning and using the old design of the tip, and 46.93 ± 7.15 µm with a new strategy of intraoral scanning and using the old design of the tip. No difference was found in the trueness and precision data extracted using the two different programs of superimposition Geomagic Control X and Medit Compare. Conclusions: The outcomes of this study showed that the latest version of I-Medit 500 with the use of a new tip seems to be promising in terms of accuracy when a full arch needs to be scanned. Moreover, Medit Compare, which is an application of Medit IOS software, can be used to calculate IOS accuracy.

Zygomatic implant rehabilitation is a challenging procedure that requires an accurate prosthetic and implant plan. The aim of this study was to evaluate the malar bone available for three-dimensional zygomatic implant placement on the possible trajectories exhibiting optimal occlusal emergence. After a preliminary analysis on 30 computed tomography (CT) scans of dentate patients to identify the ideal implant emergencies, we used 80 CT scans of edentulous patients to create two sagittal planes representing the possible trajectories of the anterior and posterior zygomatic implants. These planes were rotated clockwise on the ideal emergence points and three different hypothetical implant trajectories per zygoma were drawn for each slice. Then, the engageable malar bone and intra- and extra-sinus paths were measured. It was possible to identify the ideal implant emergences via anatomical landmarks with a high predictability. Significant differences were evident between males and females, between implants featuring anterior and those featuring posterior emergences, and between the different trajectories. The use of internal trajectories provided better bone engagement but required a higher intra-sinus path. A significant association was found between higher intra-sinus paths and lower crestal bone heights.

Aim: the aim of this in vitro study was to test whether the implant placement accuracy and the operating time can be influenced by the operator&rsquo, s experience. Materials and methods: sixteen models underwent a (Cone Beam Computer Tomography) CBCT and implant positioning was digitally planned on this. The models were randomly assigned to four operators with different levels of surgical experience. One hundred and twelve implant sites were drilled using a dynamic navigation system and operating times were measured. Based on postoperative CBCTs, dental implants were virtually inserted and superimposed over the planned ones. Two-dimensional and 3D deviations between planned and virtually inserted implants were measured at the entry point and at the apical point. Angular and vertical errors were also calculated. Results: considering coronal and apical 3D deviations, no statistically significant differences were found between the four operators (p = 0.27, p = 0.06). Some vectorial components of the deviation at the apical point and the angular errors of some operators differed from each other. Conclusions: within the limitations of this study, dynamic navigation can be considered a reliable technique both for experienced and novice clinicians.